Ideas of Bertrand Russell, by Theme
[British, 1872 - 1970, Born at Trelleck. Professor at Cambridge (Trinity). Taught Wittgenstein. Imprisoned for pacificism. Campaigner against nuclear weapons. Died in N. Wales.]
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1. Philosophy / A. Wisdom / 1. Nature of Wisdom
21584
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A sense of timelessness is essential to wisdom
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1. Philosophy / C. History of Philosophy / 5. Modern Philosophy / b. Modern philosophy beginnings
11006
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Russell started a whole movement in philosophy by providing an analysis of descriptions [Read]
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1. Philosophy / D. Nature of Philosophy / 1. Philosophy
5361
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Philosophers must get used to absurdities
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1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
5368
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Philosophy verifies that our hierarchy of instinctive beliefs is harmonious and consistent
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1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / a. Philosophy as worldly
23025
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Philosophers should be more inductive, and test results by their conclusions, not their self-evidence
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1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / e. Philosophy as reason
17641
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Discoveries in mathematics can challenge philosophy, and offer it a new foundation
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1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
21572
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Philosophical disputes are mostly hopeless, because philosophers don't understand each other
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1. Philosophy / E. Nature of Metaphysics / 2. Possibility of Metaphysics
5432
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Metaphysics cannot give knowledge of the universe as a whole
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1. Philosophy / E. Nature of Metaphysics / 3. Metaphysical Systems
21571
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Philosophical systems are interesting, but we now need a more objective scientific philosophy
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21574
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Hegel's confusions over 'is' show how vast systems can be built on simple errors
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21587
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Philosophers sometimes neglect truth and distort facts to attain a nice system
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1. Philosophy / E. Nature of Metaphysics / 4. Metaphysics as Science
21582
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Physicists accept particles, points and instants, while pretending they don't do metaphysics
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6095
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The business of metaphysics is to describe the world
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1. Philosophy / F. Analytic Philosophy / 1. Nature of Analysis
14122
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Analysis gives us nothing but the truth - but never the whole truth
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6118
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Philosophy is logical analysis, followed by synthesis
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6420
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Only by analysing is progress possible in philosophy
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6432
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Analysis gives new knowledge, without destroying what we already have
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1. Philosophy / F. Analytic Philosophy / 5. Linguistic Analysis
7529
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All philosophy should begin with an analysis of propositions
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14109
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The study of grammar is underestimated in philosophy
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14456
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'Socrates is human' expresses predication, and 'Socrates is a man' expresses identity
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21552
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Common speech is vague; its vocabulary and syntax must be modified, for precision
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1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
21546
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We can't sharply distinguish variables, domains and values, if symbols frighten us
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21573
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When problems are analysed properly, they are either logical, or not philosophical at all
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6116
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A logical language would show up the fallacy of inferring reality from ordinary language
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1. Philosophy / F. Analytic Philosophy / 7. Limitations of Analysis
14165
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Analysis falsifies, if when the parts are broken down they are not equivalent to their sum
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1. Philosophy / G. Scientific Philosophy / 3. Scientism
5434
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Philosophy is similar to science, and has no special source of wisdom
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8378
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Philosophers usually learn science from each other, not from science
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6117
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Philosophy should be built on science, to reduce error
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2. Reason / A. Nature of Reason / 6. Coherence
17638
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If one proposition is deduced from another, they are more certain together than alone
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2. Reason / B. Laws of Thought / 1. Laws of Thought
5396
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Three Laws of Thought: identity, contradiction, and excluded middle
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5405
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The law of contradiction is not a 'law of thought', but a belief about things
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2. Reason / B. Laws of Thought / 3. Non-Contradiction
17632
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Non-contradiction was learned from instances, and then found to be indubitable
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2. Reason / B. Laws of Thought / 6. Ockham's Razor
6106
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Reducing entities and premisses makes error less likely
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2. Reason / D. Definition / 3. Types of Definition
14426
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A definition by 'extension' enumerates items, and one by 'intension' gives a defining property
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2. Reason / D. Definition / 7. Contextual Definition
21560
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Any linguistic expression may lack meaning when taken out of context
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2. Reason / D. Definition / 11. Ostensive Definition
21551
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Empirical words need ostensive definition, which makes them egocentric
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2. Reason / D. Definition / 13. Against Definition
14115
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Definition by analysis into constituents is useless, because it neglects the whole
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14159
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In mathematics definitions are superfluous, as they name classes, and it all reduces to primitives
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2. Reason / F. Fallacies / 2. Infinite Regress
14148
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Infinite regresses have propositions made of propositions etc, with the key term reappearing
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2. Reason / F. Fallacies / 8. Category Mistake / a. Category mistakes
18002
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As well as a truth value, propositions have a range of significance for their variables
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21561
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'The number one is bald' or 'the number one is fond of cream cheese' are meaningless
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8468
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The sentence 'procrastination drinks quadruplicity' is meaningless, rather than false [Orenstein]
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6437
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The theory of types makes 'Socrates and killing are two' illegitimate
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3. Truth / A. Truth Problems / 1. Truth
5420
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Truth is a property of a belief, but dependent on its external relations, not its internal qualities
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3. Truth / A. Truth Problems / 5. Truth Bearers
14102
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What is true or false is not mental, and is best called 'propositions'
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5419
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Truth and falsehood are properties of beliefs and statements
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5784
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In its primary and formal sense, 'true' applies to propositions, not beliefs
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6442
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Truth belongs to beliefs, not to propositions and sentences
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3. Truth / A. Truth Problems / 7. Falsehood
5417
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A good theory of truth must make falsehood possible
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16477
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Asserting not-p is saying p is false
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3. Truth / B. Truthmakers / 1. For Truthmakers
5777
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The truth or falsehood of a belief depends upon a fact to which the belief 'refers'
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3. Truth / B. Truthmakers / 5. What Makes Truths / a. What makes truths
6090
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Facts make propositions true or false, and are expressed by whole sentences
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3. Truth / B. Truthmakers / 6. Making Negative Truths
21544
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It seems that when a proposition is false, something must fail to subsist
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3. Truth / B. Truthmakers / 8. Making General Truths
18348
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Not only atomic truths, but also general and negative truths, have truth-makers [Rami]
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3. Truth / C. Correspondence Truth / 1. Correspondence Truth
6343
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For Russell, both propositions and facts are arrangements of objects, so obviously they correspond [Horwich]
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7395
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Truth as congruence may work for complex beliefs, but not for simple beliefs about existence [Joslin]
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5428
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Beliefs are true if they have corresponding facts, and false if they don't
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5783
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Propositions of existence, generalities, disjunctions and hypotheticals make correspondence tricky
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3. Truth / D. Coherence Truth / 1. Coherence Truth
5421
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The coherence theory says falsehood is failure to cohere, and truth is fitting into a complete system of Truth
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3. Truth / D. Coherence Truth / 2. Coherence Truth Critique
5423
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If we suspend the law of contradiction, nothing will appear to be incoherent
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5422
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More than one coherent body of beliefs seems possible
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5424
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Coherence is not the meaning of truth, but an important test for truth
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3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
14454
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An argument 'satisfies' a function φx if φa is true
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3. Truth / H. Deflationary Truth / 1. Redundant Truth
14176
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"The death of Caesar is true" is not the same proposition as "Caesar died"
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4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
5401
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The mortality of Socrates is more certain from induction than it is from deduction
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14453
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The Darapti syllogism is fallacious: All M is S, all M is P, so some S is P' - but if there is no M?
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4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃
16484
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There are four experiences that lead us to talk of 'some' things
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4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
14113
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The null class is a fiction
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4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
6103
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Normally a class with only one member is a problem, because the class and the member are identical
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4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
14427
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We can enumerate finite classes, but an intensional definition is needed for infinite classes
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4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / b. Axiom of Extensionality I
14428
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Members define a unique class, whereas defining characteristics are numerous
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4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / f. Axiom of Infinity V
14440
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We may assume that there are infinite collections, as there is no logical reason against them
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14447
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Infinity says 'for any inductive cardinal, there is a class having that many terms'
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4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
14443
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The British parliament has one representative selected from each constituency
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14445
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Choice shows that if any two cardinals are not equal, one must be the greater
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14444
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Choice is equivalent to the proposition that every class is well-ordered
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14446
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We can pick all the right or left boots, but socks need Choice to insure the representative class
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4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / p. Axiom of Reducibility
18130
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Axiom of Reducibility: there is always a function of the lowest possible order in a given level [Bostock]
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14459
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Reducibility: a family of functions is equivalent to a single type of function
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4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / c. Logical sets
21563
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The 'no classes' theory says the propositions just refer to the members
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14461
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Propositions about classes can be reduced to propositions about their defining functions
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4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets
15894
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Russell invented the naïve set theory usually attributed to Cantor [Lavine]
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4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
14126
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Order rests on 'between' and 'separation'
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14127
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Order depends on transitive asymmetrical relations
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4. Formal Logic / F. Set Theory ST / 7. Natural Sets
8469
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Russell's proposal was that only meaningful predicates have sets as their extensions [Orenstein]
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4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
11064
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Classes can be reduced to propositional functions [Hanna]
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7548
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Classes, grouped by a convenient property, are logical constructions
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8745
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Classes are logical fictions, and are not part of the ultimate furniture of the world
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6436
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I gradually replaced classes with properties, and they ended as a symbolic convenience
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4. Formal Logic / G. Formal Mereology / 1. Mereology
14121
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The part-whole relation is ultimate and indefinable
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5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
6110
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Subject-predicate logic (and substance-attribute metaphysics) arise from Aryan languages
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5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
21588
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Logic gives the method of research in philosophy
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6107
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It is logic, not metaphysics, that is fundamental to philosophy
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5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
14452
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All the propositions of logic are completely general
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16486
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The physical world doesn't need logic, but the mental world does
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5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
21495
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Theoretical and practical politics are both concerned with the best lives for individuals
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5. Theory of Logic / A. Overview of Logic / 8. Logic of Mathematics
14462
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In modern times, logic has become mathematical, and mathematics has become logical
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5. Theory of Logic / B. Logical Consequence / 5. Modus Ponens
5395
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Demonstration always relies on the rule that anything implied by a truth is true
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5. Theory of Logic / B. Logical Consequence / 8. Material Implication
14108
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It would be circular to use 'if' and 'then' to define material implication
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14106
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Implication cannot be defined
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5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
14167
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The only classes are things, predicates and relations
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22329
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Logic is highly general truths abstracted from reality [Glock]
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12444
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Logic is concerned with the real world just as truly as zoology
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10057
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Logic can only assert hypothetical existence
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14464
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Logic can be known a priori, without study of the actual world
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5. Theory of Logic / C. Ontology of Logic / 3. If-Thenism
10053
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Geometrical axioms imply the propositions, but the former may not be true
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5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
21539
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Excluded middle can be stated psychologically, as denial of p implies assertion of not-p
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18944
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Russell's theories aim to preserve excluded middle (saying all sentences are T or F) [Sawyer]
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2947
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Questions wouldn't lead anywhere without the law of excluded middle
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5. Theory of Logic / E. Structures of Logic / 1. Logical Form
7758
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'Elizabeth = Queen of England' is really a predication, not an identity-statement [Lycan]
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6092
|
In a logically perfect language, there will be just one word for every simple object
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6101
|
Romulus does not occur in the proposition 'Romulus did not exist'
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6115
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Vagueness, and simples being beyond experience, are obstacles to a logical language
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7528
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Leibniz bases everything on subject/predicate and substance/property propositions
|
5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives
23476
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Logical constants seem to be entities in propositions, but are actually pure form
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23477
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We use logical notions, so they must be objects - but I don't know what they really are
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21586
|
The logical connectives are not objects, but are formal, and need a context
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21597
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Logical connectives have the highest precision, yet are infected by the vagueness of true and false [Williamson]
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5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / b. Basic connectives
14105
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There seem to be eight or nine logical constants
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5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / c. not
18722
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Negations are not just reversals of truth-value, since that can happen without negation [Wittgenstein]
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16489
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Is it possible to state every possible truth about the whole course of nature without using 'not'?
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5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / e. or
16479
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'Or' expresses hesitation, in a dog at a crossroads, or birds risking grabbing crumbs
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16480
|
A disjunction expresses indecision
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16481
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'Or' expresses a mental state, not something about the world
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16483
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Disjunction may also arise in practice if there is imperfect memory.
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16487
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Maybe the 'or' used to describe mental states is not the 'or' of logic
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5. Theory of Logic / E. Structures of Logic / 3. Constants in Logic
14104
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Constants are absolutely definite and unambiguous
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5. Theory of Logic / E. Structures of Logic / 4. Variables in Logic
14114
|
Variables don't stand alone, but exist as parts of propositional functions
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5772
|
The idea of a variable is fundamental
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5. Theory of Logic / E. Structures of Logic / 5. Functions in Logic
21566
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'Propositional functions' are ambiguous until the variable is given a value
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5. Theory of Logic / F. Referring in Logic / 1. Naming / a. Names
6102
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You can understand 'author of Waverley', but to understand 'Scott' you must know who it applies to
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10423
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There are a set of criteria for pinning down a logically proper name [Sainsbury]
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5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
18941
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Names don't have a sense, but are disguised definite descriptions [Sawyer]
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4945
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Russell says names are not denotations, but definite descriptions in disguise [Kripke]
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18942
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Russell says a name contributes a complex of properties, rather than an object [Sawyer]
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7745
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Are names descriptions, if the description is unknown, false, not special, or contains names? [McCullogh]
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5386
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Proper names are really descriptions, and can be replaced by a description in a person's mind
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7744
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Treat description using quantifiers, and treat proper names as descriptions [McCullogh]
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10450
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Russell admitted that even names could also be used as descriptions [Bach]
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14458
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Asking 'Did Homer exist?' is employing an abbreviated description
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14457
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Names are really descriptions, except for a few words like 'this' and 'that'
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5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
10449
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Logically proper names introduce objects; definite descriptions introduce quantifications [Bach]
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15159
|
The meaning of a logically proper name is its referent, but most names are not logically proper [Soames]
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6410
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The only real proper names are 'this' and 'that'; the rest are really definite descriptions. [Grayling]
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5. Theory of Logic / F. Referring in Logic / 1. Naming / d. Singular terms
7757
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"Nobody" is not a singular term, but a quantifier [Lycan]
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2612
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Russell rewrote singular term names as predicates [Ayer]
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5. Theory of Logic / F. Referring in Logic / 1. Naming / e. Empty names
18943
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Russell implies that all sentences containing empty names are false [Sawyer]
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10426
|
A name has got to name something or it is not a name
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6439
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Names are meaningless unless there is an object which they designate
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5. Theory of Logic / F. Referring in Logic / 1. Naming / f. Names eliminated
7311
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The only genuine proper names are 'this' and 'that'
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5. Theory of Logic / F. Referring in Logic / 2. Descriptions / a. Descriptions
14455
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'I met a unicorn' is meaningful, and so is 'unicorn', but 'a unicorn' is not
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5. Theory of Logic / F. Referring in Logic / 2. Descriptions / b. Definite descriptions
6411
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Critics say definite descriptions can refer, and may not embody both uniqueness and existence claims [Grayling]
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10433
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Definite descriptions fail to refer in three situations, so they aren't essentially referring [Sainsbury]
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5385
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The phrase 'a so-and-so' is an 'ambiguous' description'; 'the so-and-so' (singular) is a 'definite' description
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5. Theory of Logic / F. Referring in Logic / 2. Descriptions / c. Theory of definite descriptions
1608
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The theory of descriptions eliminates the name of the entity whose existence was presupposed [Quine]
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7754
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Russell's theory explains non-existents, negative existentials, identity problems, and substitutivity [Lycan]
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21529
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Russell showed how to define 'the', and thereby reduce the ontology of logic [Lackey]
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6333
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The theory of definite descriptions reduces the definite article 'the' to the concepts of predicate logic [Horwich]
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6412
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Russell implies that 'the baby is crying' is only true if the baby is unique [Grayling]
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7743
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Russell explained descriptions with quantifiers, where Frege treated them as names [McCullogh]
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7310
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Russell avoids non-existent objects by denying that definite descriptions are proper names [Miller,A]
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12006
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Denying definite description sentences are subject-predicate in form blocks two big problems [Forbes,G]
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4569
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Russell says apparent referring expressions are really assertions about properties [Cooper,DE]
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11009
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Russell's theory must be wrong if it says all statements about non-existents are false [Read]
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21549
|
The theory of descriptions lacks conventions for the scope of quantifiers [Lackey]
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12796
|
Non-count descriptions don't threaten Russell's theory, which is only about singulars [Laycock]
|
7532
|
Denoting is crucial in Russell's account of mathematics, for identifying classes [Monk]
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11988
|
Russell's analysis means molecular sentences are ambiguous over the scope of the description [Kaplan]
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5. Theory of Logic / G. Quantification / 1. Quantification
14137
|
'Any' is better than 'all' where infinite classes are concerned
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5. Theory of Logic / G. Quantification / 3. Objectual Quantification
6061
|
Existence is entirely expressed by the existential quantifier [McGinn]
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5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
18273
|
Logical truths are known by their extreme generality
|
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
17640
|
Finding the axioms may be the only route to some new results
|
17629
|
Which premises are ultimate varies with context
|
17630
|
The sources of a proof are the reasons why we believe its conclusion
|
6109
|
Some axioms may only become accepted when they lead to obvious conclusions
|
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / a. Achilles paradox
7557
|
To solve Zeno's paradox, reject the axiom that the whole has more terms than the parts
|
14149
|
The Achilles Paradox concerns the one-one correlation of infinite classes
|
21585
|
The tortoise won't win, because infinite instants don't compose an infinitely long time
|
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / d. Richard's paradox
21565
|
Richard's puzzle uses the notion of 'definition' - but that cannot be defined
|
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / c. Burali-Forti's paradox
15895
|
Russell discovered the paradox suggested by Burali-Forti's work [Lavine]
|
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / d. Russell's paradox
13365
|
Russell's Paradox is a stripped-down version of Cantor's Paradox [Priest,G]
|
10711
|
Russell's paradox means we cannot assume that every property is collectivizing [Potter]
|
6407
|
The class of classes which lack self-membership leads to a contradiction [Grayling]
|
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
21564
|
Vicious Circle: what involves ALL must not be one of those ALL
|
21567
|
'All judgements made by Epimenedes are true' needs the judgements to be of the same type
|
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / c. Grelling's paradox
16475
|
A 'heterological' predicate can't be predicated of itself; so is 'heterological' heterological? Yes=no!
|
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
10059
|
In mathematic we are ignorant of both subject-matter and truth
|
6. Mathematics / A. Nature of Mathematics / 2. Geometry
14151
|
Pure geometry is deductive, and neutral over what exists
|
14153
|
In geometry, empiricists aimed at premisses consistent with experience
|
14152
|
In geometry, Kant and idealists aimed at the certainty of the premisses
|
14154
|
Geometry throws no light on the nature of actual space
|
14155
|
Two points have a line joining them (descriptive), a distance (metrical), and a whole line (projective) [PG]
|
14442
|
If straight lines were like ratios they might intersect at a 'gap', and have no point in common
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
14144
|
Ordinals result from likeness among relations, as cardinals from similarity among classes
|
18254
|
Russell's approach had to treat real 5/8 as different from rational 5/8 [Dummett]
|
14438
|
New numbers solve problems: negatives for subtraction, fractions for division, complex for equations
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
14128
|
Some claim priority for the ordinals over cardinals, but there is no logical priority between them
|
14129
|
Ordinals presuppose two relations, where cardinals only presuppose one
|
14132
|
Properties of numbers don't rely on progressions, so cardinals may be more basic
|
13510
|
Could a number just be something which occurs in a progression? [Hart,WD]
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
14139
|
Transfinite ordinals don't obey commutativity, so their arithmetic is quite different from basic arithmetic
|
14141
|
Ordinals are defined through mathematical induction
|
14142
|
Ordinals are types of series of terms in a row, rather than the 'nth' instance
|
14145
|
For Cantor ordinals are types of order, not numbers
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
14146
|
We aren't sure if one cardinal number is always bigger than another
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
14135
|
Real numbers are a class of rational numbers (and so not really numbers at all)
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / i. Reals from cuts
14436
|
A series can be 'Cut' in two, where the lower class has no maximum, the upper no minimum
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / j. Complex numbers
14439
|
A complex number is simply an ordered couple of real numbers
|
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / m. One
14421
|
Discovering that 1 is a number was difficult
|
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / b. Quantity
14123
|
Some quantities can't be measured, and some non-quantities are measurable
|
14158
|
Quantity is not part of mathematics, where it is replaced by order
|
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / c. Counting procedure
14120
|
Counting explains none of the real problems about the foundations of arithmetic
|
14424
|
Numbers are needed for counting, so they need a meaning, and not just formal properties
|
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / e. Counting by correlation
14118
|
We can define one-to-one without mentioning unity
|
6. Mathematics / A. Nature of Mathematics / 4. Using Numbers / f. Arithmetic
14441
|
The formal laws of arithmetic are the Commutative, the Associative and the Distributive
|
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
14119
|
We do not currently know whether, of two infinite numbers, one must be greater than the other
|
14133
|
There are cardinal and ordinal theories of infinity (while continuity is entirely ordinal)
|
14420
|
Infinity and continuity used to be philosophy, but are now mathematics
|
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / b. Mark of the infinite
7556
|
A collection is infinite if you can remove some terms without diminishing its number
|
14134
|
Infinite numbers are distinguished by disobeying induction, and the part equalling the whole
|
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
14143
|
ω names the whole series, or the generating relation of the series of ordinal numbers
|
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
14138
|
You can't get a new transfinite cardinal from an old one just by adding finite numbers to it
|
14140
|
For every transfinite cardinal there is an infinite collection of transfinite ordinals
|
6. Mathematics / B. Foundations for Mathematics / 2. Proof in Mathematics
17627
|
It seems absurd to prove 2+2=4, where the conclusion is more certain than premises
|
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
10052
|
Geometry is united by the intuitive axioms of projective geometry [Musgrave]
|
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / a. Axioms for numbers
14124
|
Axiom of Archimedes: a finite multiple of a lesser magnitude can always exceed a greater
|
14431
|
The definition of order needs a transitive relation, to leap over infinite intermediate terms
|
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / d. Peano arithmetic
7530
|
Russell tried to replace Peano's Postulates with the simple idea of 'class' [Monk]
|
18246
|
Dedekind failed to distinguish the numbers from other progressions [Shapiro]
|
14422
|
Any founded, non-repeating series all reachable in steps will satisfy Peano's axioms
|
14423
|
'0', 'number' and 'successor' cannot be defined by Peano's axioms
|
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
14125
|
Finite numbers, unlike infinite numbers, obey mathematical induction
|
14147
|
Denying mathematical induction gave us the transfinite
|
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / b. Greek arithmetic
14116
|
Numbers were once defined on the basis of 1, but neglected infinities and +
|
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / c. Fregean numbers
14117
|
Numbers are properties of classes
|
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / d. Hume's Principle
14425
|
A number is something which characterises collections of the same size
|
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
14434
|
What matters is the logical interrelation of mathematical terms, not their intrinsic nature
|
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
9977
|
Ordinals can't be defined just by progression; they have intrinsic qualities
|
6. Mathematics / C. Sources of Mathematics / 1. Mathematical Platonism / b. Against mathematical platonism
14162
|
Mathematics doesn't care whether its entities exist
|
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
17628
|
Arithmetic was probably inferred from relationships between physical objects
|
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / c. Against mathematical empiricism
5399
|
Maths is not known by induction, because further instances are not needed to support it
|
6. Mathematics / C. Sources of Mathematics / 5. Numbers as Adjectival
14465
|
Maybe numbers are adjectives, since 'ten men' grammatically resembles 'white men'
|
6. Mathematics / C. Sources of Mathematics / 6. Logicism / a. Early logicism
14103
|
Pure mathematics is the class of propositions of the form 'p implies q'
|
13414
|
For Russell, numbers are sets of equivalent sets [Benacerraf]
|
6108
|
Maths can be deduced from logical axioms and the logic of relations
|
6423
|
We tried to define all of pure maths using logical premisses and concepts
|
6. Mathematics / C. Sources of Mathematics / 6. Logicism / b. Type theory
21555
|
For 'x is a u' to be meaningful, u must be one range of individuals (or 'type') higher than x
|
18003
|
In 'x is a u', x and u must be of different types, so 'x is an x' is generally meaningless [Magidor]
|
10418
|
Type theory seems an extreme reaction, since self-exemplification is often innocuous [Swoyer]
|
10047
|
Russell's improvements blocked mathematics as well as paradoxes, and needed further axioms [Musgrave]
|
23478
|
Type theory means that features shared by different levels cannot be expressed [Morris,M]
|
23457
|
Type theory cannot identify features across levels (because such predicates break the rules) [Morris,M]
|
21556
|
Classes are defined by propositional functions, and functions are typed, with an axiom of reducibility [Lackey]
|
6. Mathematics / C. Sources of Mathematics / 6. Logicism / c. Neo-logicism
21718
|
Ramified types can be defended as a system of intensional logic, with a 'no class' view of sets [Linsky,B]
|
6. Mathematics / C. Sources of Mathematics / 7. Formalism
21570
|
Numbers are just verbal conveniences, which can be analysed away
|
6425
|
Formalism can't apply numbers to reality, so it is an evasion
|
6424
|
Formalists say maths is merely conventional marks on paper, like the arbitrary rules of chess
|
6. Mathematics / C. Sources of Mathematics / 9. Fictional Mathematics
6104
|
Numbers are classes of classes, and hence fictions of fictions
|
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
6426
|
Intuitionism says propositions are only true or false if there is a method of showing it
|
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
21559
|
We need rules for deciding which norms are predicative (unless none of them are)
|
21558
|
'Predicative' norms are those which define a class
|
18126
|
A set does not exist unless at least one of its specifications is predicative [Bostock]
|
18128
|
Russell is a conceptualist here, saying some abstracta only exist because definitions create them [Bostock]
|
18124
|
Vicious Circle says if it is expressed using the whole collection, it can't be in the collection [Bostock]
|
21568
|
A one-variable function is only 'predicative' if it is one order above its arguments
|
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / e. Psychologism
14449
|
There is always something psychological about inference
|
7. Existence / A. Nature of Existence / 1. Nature of Existence
14463
|
Existence can only be asserted of something described, not of something named
|
7. Existence / A. Nature of Existence / 3. Being / a. Nature of Being
11010
|
Being is what belongs to every possible object of thought
|
7. Existence / A. Nature of Existence / 3. Being / b. Being and existence
14161
|
Many things have being (as topics of propositions), but may not have actual existence
|
7. Existence / A. Nature of Existence / 6. Criterion for Existence
14173
|
What exists has causal relations, but non-existent things may also have them
|
7. Existence / B. Change in Existence / 4. Events / b. Events as primitive
6402
|
In 1927, Russell analysed force and matter in terms of events [Grayling]
|
7. Existence / C. Structure of Existence / 5. Supervenience / c. Significance of supervenience
16045
|
General facts supervene on particular facts, but cannot be inferred from them [Bennett,K]
|
7. Existence / C. Structure of Existence / 6. Fundamentals / d. Logical atoms
21684
|
Atomic facts may be inferrable from others, but never from non-atomic facts
|
21708
|
Russell's new logical atomist was of particulars, universals and facts (not platonic propositions) [Linsky,B]
|
19051
|
Russell's atomic facts are actually compounds, and his true logical atoms are sense data [Quine]
|
6089
|
Logical atomism aims at logical atoms as the last residue of analysis
|
6100
|
Once you have enumerated all the atomic facts, there is a further fact that those are all the facts
|
6105
|
Logical atoms aims to get down to ultimate simples, with their own unique reality
|
6113
|
To mean facts we assert them; to mean simples we name them
|
6114
|
'Simples' are not experienced, but are inferred at the limits of analysis
|
21722
|
Better to construct from what is known, than to infer what is unknown
|
10968
|
Russell gave up logical atomism because of negative, general and belief propositions [Read]
|
21681
|
Given all true atomic propositions, in theory every other truth can thereby be deduced
|
6419
|
In 1899-1900 I adopted the philosophy of logical atomism
|
6438
|
Complex things can be known, but not simple things
|
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
6472
|
Continuity is a sufficient criterion for the identity of a rock, but not for part of a smooth fluid
|
7. Existence / D. Theories of Reality / 1. Realism
21538
|
If two people perceive the same object, the object of perception can't be in the mind
|
7. Existence / D. Theories of Reality / 2. Reality
5370
|
Space is neutral between touch and sight, so it cannot really be either of them
|
7. Existence / D. Theories of Reality / 3. Anti-realism
7545
|
Visible things are physical and external, but only exist when viewed
|
7. Existence / D. Theories of Reality / 6. Fictionalism
14429
|
Classes are logical fictions, made from defining characteristics
|
7. Existence / D. Theories of Reality / 7. Facts / a. Facts
21709
|
You can't name all the facts, so they are not real, but are what propositions assert
|
6111
|
As propositions can be put in subject-predicate form, we wrongly infer that facts have substance-quality form
|
6434
|
Facts are everything, except simples; they are either relations or qualities
|
7. Existence / D. Theories of Reality / 7. Facts / b. Types of fact
18376
|
Russell asserts atomic, existential, negative and general facts [Armstrong]
|
7. Existence / D. Theories of Reality / 7. Facts / c. Facts and truths
5418
|
In a world of mere matter there might be 'facts', but no truths
|
7. Existence / D. Theories of Reality / 7. Facts / d. Negative facts
22315
|
There can't be a negative of a complex, which is negated by its non-existence [Potter]
|
22316
|
A positive and negative fact have the same constituents; their difference is primitive
|
7. Existence / D. Theories of Reality / 8. States of Affairs
5465
|
Modern trope theory tries, like logical atomism, to reduce things to elementary states [Ellis]
|
7. Existence / D. Theories of Reality / 9. Vagueness / d. Vagueness as linguistic
9051
|
Since natural language is not precise it cannot be in the province of logic [Keefe/Smith]
|
9054
|
Vagueness is only a characteristic of representations, such as language
|
7. Existence / D. Theories of Reality / 10. Ontological Commitment / a. Ontological commitment
6060
|
'Existence' means that a propositional function is sometimes true
|
7. Existence / D. Theories of Reality / 10. Ontological Commitment / e. Ontological commitment problems
18775
|
Russell showed that descriptions may not have ontological commitment [Linsky,B]
|
7. Existence / E. Categories / 3. Proposed Categories
14163
|
Four classes of terms: instants, points, terms at instants only, and terms at instants and points
|
7533
|
The Theory of Description dropped classes and numbers, leaving propositions, individuals and universals [Monk]
|
8. Modes of Existence / A. Relations / 1. Nature of Relations
21341
|
Philosophers of logic and maths insisted that a vocabulary of relations was essential [Heil]
|
21534
|
The only thing we can say about relations is that they relate
|
21540
|
Relational propositions seem to be 'about' their terms, rather than about the relation
|
21562
|
There is no complexity without relations, so no propositions, and no truth
|
5371
|
Because we depend on correspondence, we know relations better than we know the items that relate
|
5407
|
That Edinburgh is north of London is a non-mental fact, so relations are independent universals
|
21576
|
With asymmetrical relations (before/after) the reduction to properties is impossible
|
8. Modes of Existence / A. Relations / 4. Formal Relations / a. Types of relation
10586
|
'Reflexiveness' holds between a term and itself, and cannot be inferred from symmetry and transitiveness
|
14432
|
'Asymmetry' is incompatible with its converse; a is husband of b, so b can't be husband of a
|
14430
|
If a relation is symmetrical and transitive, it has to be reflexive
|
8. Modes of Existence / A. Relations / 4. Formal Relations / b. Equivalence relation
10585
|
Symmetrical and transitive relations are formally like equality
|
8. Modes of Existence / B. Properties / 11. Properties as Sets
9127
|
Russell refuted Frege's principle that there is a set for each property [Sorensen]
|
21575
|
When we attribute a common quality to a group, we can forget the quality and just talk of the group
|
8. Modes of Existence / B. Properties / 12. Denial of Properties
6063
|
Russell can't attribute existence to properties [McGinn]
|
8. Modes of Existence / B. Properties / 13. Tropes / b. Critique of tropes
14327
|
Trope theorists cannot explain how tropes resemble each other [Mumford]
|
8. Modes of Existence / D. Universals / 1. Universals
5383
|
Every complete sentence must contain at least one word (a verb) which stands for a universal
|
4428
|
Propositions express relations (prepositions and verbs) as well as properties (nouns and adjectives)
|
5406
|
Confused views of reality result from thinking that only nouns and adjectives represent universals
|
4479
|
All universals are like the relation "is north of", in having no physical location at all [Loux]
|
8. Modes of Existence / D. Universals / 2. Need for Universals
21710
|
We know a universal in 'yellow differs from blue' or 'yellow resembles blue less than green does'
|
4427
|
Every sentence contains at least one word denoting a universal, so we need universals to know truth
|
4030
|
Russell claims that universals are needed to explain a priori knowledge (as their relations) [Mellor/Oliver]
|
8. Modes of Existence / D. Universals / 4. Uninstantiated Universals
5409
|
Normal existence is in time, so we must say that universals 'subsist'
|
8. Modes of Existence / D. Universals / 5. Universals as Concepts
5408
|
If we identify whiteness with a thought, we can never think of it twice; whiteness is the object of a thought
|
8. Modes of Existence / E. Nominalism / 2. Resemblance Nominalism
4441
|
'Resemblance Nominalism' won't work, because the theory treats resemblance itself as a universal
|
8. Modes of Existence / E. Nominalism / 3. Predicate Nominalism
6440
|
Universals can't just be words, because words themselves are universals
|
8. Modes of Existence / E. Nominalism / 4. Concept Nominalism
4429
|
If we consider whiteness to be merely a mental 'idea', we rob it of its universality
|
9. Objects / A. Existence of Objects / 1. Physical Objects
6473
|
Physical things are series of appearances whose matter obeys physical laws
|
14732
|
A perceived physical object is events grouped around a centre
|
9. Objects / A. Existence of Objects / 3. Objects in Thought
7781
|
I call an object of thought a 'term'. This is a wide concept implying unity and existence.
|
21536
|
When I perceive a melody, I do not perceive the notes as existing
|
9. Objects / A. Existence of Objects / 4. Impossible objects
21531
|
Common sense agrees with Meinong (rather than Russell) that 'Pegasus is a flying horse' is true [Lackey]
|
18777
|
If the King of France is not bald, and not not-bald, this violates excluded middle [Linsky,B]
|
21545
|
I prefer to deny round squares, and deal with the difficulties by the theory of denoting
|
21547
|
On Meinong's principles 'the existent round square' has to exist
|
9. Objects / A. Existence of Objects / 5. Simples
14166
|
Unities are only in propositions or concepts, and nothing that exists has unity
|
9. Objects / A. Existence of Objects / 5. Individuation / c. Individuation by location
21535
|
Objects only exist if they 'occupy' space and time
|
9. Objects / B. Unity of Objects / 1. Unifying an Object / a. Intrinsic unification
14164
|
The only unities are simples, or wholes composed of parts
|
9. Objects / B. Unity of Objects / 1. Unifying an Object / b. Unifying aggregates
14112
|
A set has some sort of unity, but not enough to be a 'whole'
|
9. Objects / B. Unity of Objects / 2. Substance / e. Substance critique
6465
|
We need not deny substance, but there seems no reason to assert it
|
6471
|
The assumption by physicists of permanent substance is not metaphysically legitimate
|
14733
|
An object produces the same percepts with or without a substance, so that is irrelevant to science
|
9. Objects / D. Essence of Objects / 3. Individual Essences
14435
|
The essence of individuality is beyond description, and hence irrelevant to science
|
9. Objects / D. Essence of Objects / 15. Against Essentialism
14170
|
Change is obscured by substance, a thing's nature, subject-predicate form, and by essences
|
9. Objects / F. Identity among Objects / 7. Indiscernible Objects
14107
|
Terms are identical if they belong to all the same classes
|
11849
|
It at least makes sense to say two objects have all their properties in common [Wittgenstein]
|
10. Modality / A. Necessity / 2. Nature of Necessity
8375
|
'Necessary' is a predicate of a propositional function, saying it is true for all values of its argument
|
6099
|
Modal terms are properties of propositional functions, not of propositions
|
10. Modality / A. Necessity / 6. Logical Necessity
16490
|
Some facts about experience feel like logical necessities
|
10. Modality / B. Possibility / 1. Possibility
22308
|
Only the actual exists, so possibilities always reduce to actuality after full analysis
|
10. Modality / B. Possibility / 5. Contingency
21533
|
Contingency arises from tensed verbs changing the propositions to which they refer
|
10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals
12197
|
Inferring q from p only needs p to be true, and 'not-p or q' to be true
|
14450
|
All forms of implication are expressible as truth-functions
|
10. Modality / B. Possibility / 9. Counterfactuals
22303
|
It makes no sense to say that a true proposition could have been false
|
10. Modality / E. Possible worlds / 1. Possible Worlds / a. Possible worlds
5400
|
In any possible world we feel that two and two would be four
|
14460
|
If something is true in all possible worlds then it is logically necessary
|
11. Knowledge Aims / A. Knowledge / 1. Knowledge
5431
|
Knowledge cannot be precisely defined, as it merges into 'probable opinion'
|
16482
|
All our knowledge (if verbal) is general, because all sentences contain general words
|
6430
|
In epistemology we should emphasis the continuity between animal and human minds
|
11. Knowledge Aims / A. Knowledge / 4. Belief / b. Elements of beliefs
5426
|
Belief relates a mind to several things other than itself
|
5780
|
The three questions about belief are its contents, its success, and its character
|
11. Knowledge Aims / A. Knowledge / 4. Belief / d. Cause of beliefs
5366
|
We have an 'instinctive' belief in the external world, prior to all reflection
|
11. Knowledge Aims / B. Certain Knowledge / 3. Fallibilism
17637
|
The most obvious beliefs are not infallible, as other obvious beliefs may conflict
|
11. Knowledge Aims / B. Certain Knowledge / 4. The Cogito
5359
|
Descartes showed that subjective things are the most certain
|
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / a. Naïve realism
4758
|
Naïve realism leads to physics, but physics then shows that naïve realism is false
|
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / b. Direct realism
21537
|
I assume we perceive the actual objects, and not their 'presentations'
|
5377
|
'Acquaintance' is direct awareness, without inferences or judgements
|
11. Knowledge Aims / C. Knowing Reality / 1. Perceptual Realism / c. Representative realism
6510
|
Russell (1912) said phenomena only resemble reality in abstract structure [Robinson,H]
|
5372
|
There is no reason to think that objects have colours
|
21580
|
Science condemns sense-data and accepts matter, but a logical construction must link them
|
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
6466
|
Where possible, logical constructions are to be substituted for inferred entities
|
6418
|
Russell rejected phenomenalism because it couldn't account for causal relations [Grayling]
|
11. Knowledge Aims / C. Knowing Reality / 3. Idealism / a. Idealism
5373
|
'Idealism' says that everything which exists is in some sense mental
|
11. Knowledge Aims / C. Knowing Reality / 4. Solipsism
5362
|
It is not illogical to think that only myself and my mental events exist
|
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
7554
|
Self-evidence is often a mere will-o'-the-wisp
|
5412
|
Some propositions are self-evident, but their implications may also be self-evident
|
5413
|
Particular instances are more clearly self-evident than any general principles
|
5415
|
As shown by memory, self-evidence comes in degrees
|
5416
|
If self-evidence has degrees, we should accept the more self-evident as correct
|
12. Knowledge Sources / A. A Priori Knowledge / 4. A Priori as Necessities
5397
|
The rationalists were right, because we know logical principles without experience
|
12. Knowledge Sources / A. A Priori Knowledge / 9. A Priori from Concepts
4430
|
All a priori knowledge deals with the relations of universals
|
5411
|
We can know some general propositions by universals, when no instance can be given
|
12. Knowledge Sources / B. Perception / 3. Representation
6514
|
Russell's representationalism says primary qualities only show the structure of reality [Robinson,H]
|
12. Knowledge Sources / B. Perception / 4. Sense Data / a. Sense-data theory
6415
|
After 1912, Russell said sense-data are last in analysis, not first in experience [Grayling]
|
5358
|
'Sense-data' are what are immediately known in sensation, such as colours or roughnesses
|
6417
|
In 1921 Russell abandoned sense-data, and the gap between sensation and object [Grayling]
|
6474
|
Seeing is not in itself knowledge, but is separate from what is seen, such as a patch of colour
|
12. Knowledge Sources / B. Perception / 4. Sense Data / b. Nature of sense-data
6483
|
Russell held that we are aware of states of our own brain [Robinson,H]
|
8244
|
Sense-data are qualities devoid of subjectivity, which are the basis of science [Deleuze/Guattari]
|
6467
|
No sensibile is ever a datum to two people at once
|
6462
|
Sense-data are not mental, but are part of the subject-matter of physics
|
6464
|
Sense-data are usually objects within the body, but are not part of the subject
|
6463
|
Sense-data are objects, and do not contain the subject as part, the way beliefs do
|
7549
|
If my body literally lost its mind, the object seen when I see a flash would still exist
|
7553
|
Sense-data are purely physical
|
12. Knowledge Sources / B. Perception / 4. Sense Data / c. Unperceived sense-data
6459
|
We do not know whether sense-data exist as objects when they are not data
|
6460
|
'Sensibilia' are identical to sense-data, without actually being data for any mind
|
6461
|
Ungiven sense-data can no more exist than unmarried husbands
|
21583
|
When sense-data change, there must be indistinguishable sense-data in the process
|
12. Knowledge Sources / B. Perception / 4. Sense Data / d. Sense-data problems
8854
|
My 'acquaintance' with sense-data is nothing like my knowing New York [Williams,M]
|
6458
|
Individuating sense-data is difficult, because they divide when closely attended to
|
6469
|
Sense-data may be subjective, if closing our eyes can change them
|
6476
|
We cannot assume that the subject actually exists, so we cannot distinguish sensations from sense-data
|
12. Knowledge Sources / B. Perception / 5. Interpretation
6098
|
Perception goes straight to the fact, and not through the proposition
|
12. Knowledge Sources / C. Rationalism / 1. Rationalism
21577
|
Empirical truths are particular, so general truths need an a priori input of generality
|
12. Knowledge Sources / D. Empiricism / 1. Empiricism
7290
|
If Russell rejects innate ideas and direct a priori knowledge, he is left with a tabula rasa [Thompson]
|
5357
|
It is natural to begin from experience, and presumably that is the basis of knowledge
|
5389
|
Knowledge by descriptions enables us to transcend private experience
|
5382
|
We are acquainted with outer and inner sensation, memory, Self, and universals [PG]
|
16476
|
For simple words, a single experience can show that they are true
|
12. Knowledge Sources / D. Empiricism / 3. Pragmatism
6441
|
Pragmatism judges by effects, but I judge truth by causes
|
12. Knowledge Sources / D. Empiricism / 5. Empiricism Critique
21532
|
Full empiricism is not tenable, but empirical investigation is always essential
|
5376
|
I can know the existence of something with which nobody is acquainted
|
16485
|
Perception can't prove universal generalisations, so abandon them, or abandon empiricism?
|
16488
|
It is hard to explain how a sentence like 'it is not raining' can be found true by observation
|
6431
|
Empiricists seem unclear what they mean by 'experience'
|
12. Knowledge Sources / E. Direct Knowledge / 4. Memory
5414
|
Images are not memory, because they are present, and memories are of the past
|
2792
|
It is possible the world came into existence five minutes ago, complete with false memories
|
13. Knowledge Criteria / A. Justification Problems / 2. Justification Challenges / b. Gettier problem
5430
|
A true belief is not knowledge if it is reached by bad reasoning
|
5429
|
True belief is not knowledge when it is deduced from false belief
|
6444
|
True belief about the time is not knowledge if I luckily observe a stopped clock at the right moment
|
13. Knowledge Criteria / B. Internal Justification / 4. Foundationalism / c. Empirical foundations
5378
|
All knowledge (of things and of truths) rests on the foundations of acquaintance
|
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / a. Coherence as justification
17639
|
Believing a whole science is more than believing each of its propositions
|
13. Knowledge Criteria / B. Internal Justification / 5. Coherentism / b. Pro-coherentism
21579
|
Objects are treated as real when they connect with other experiences in a normal way
|
13. Knowledge Criteria / C. External Justification / 3. Reliabilism / b. Anti-reliabilism
22326
|
Knowledge needs more than a sensitive response; the response must also be appropriate
|
13. Knowledge Criteria / D. Scepticism / 5. Dream Scepticism
5365
|
Dreams can be explained fairly scientifically if we assume a physical world
|
13. Knowledge Criteria / D. Scepticism / 6. Scepticism Critique
21578
|
Global scepticism is irrefutable, but can't replace our other beliefs, and just makes us hesitate
|
14. Science / B. Scientific Theories / 1. Scientific Theory
14433
|
Mathematically expressed propositions are true of the world, but how to interpret them?
|
14. Science / B. Scientific Theories / 2. Aim of Science
5391
|
Science aims to find uniformities to which (within the limits of experience) there are no exceptions
|
14. Science / C. Induction / 2. Aims of Induction
17631
|
Induction is inferring premises from consequences
|
14. Science / C. Induction / 3. Limits of Induction
5394
|
We can't prove induction from experience without begging the question
|
5390
|
Chickens are not very good at induction, and are surprised when their feeder wrings their neck
|
5392
|
It doesn't follow that because the future has always resembled the past, that it always will
|
14. Science / D. Explanation / 3. Best Explanation / a. Best explanation
5363
|
If the cat reappears in a new position, presumably it has passed through the intermediate positions
|
5367
|
Belief in real objects makes our account of experience simpler and more systematic
|
15. Nature of Minds / A. Nature of Mind / 4. Other Minds / c. Knowing other minds
5364
|
It is hard not to believe that speaking humans are expressing thoughts, just as we do ourselves
|
6416
|
Other minds seem to exist, because their testimony supports realism about the world [Grayling]
|
15. Nature of Minds / A. Nature of Mind / 4. Other Minds / d. Other minds by analogy
5379
|
If we didn't know our own minds by introspection, we couldn't know that other people have minds
|
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
21569
|
It is good to generalise truths as much as possible
|
15. Nature of Minds / C. Capacities of Minds / 7. Seeing Resemblance
5410
|
I learn the universal 'resemblance' by seeing two shades of green, and their contrast with red
|
16. Persons / B. Nature of the Self / 6. Self as Higher Awareness
5381
|
In seeing the sun, we are acquainted with our self, but not as a permanent person
|
16. Persons / C. Self-Awareness / 3. Limits of Introspection
5380
|
In perceiving the sun, I am aware of sun sense-data, and of the perceiver of the data
|
16. Persons / D. Continuity of the Self / 2. Mental Continuity / b. Self as mental continuity
7546
|
A man is a succession of momentary men, bound by continuity and causation
|
16. Persons / E. Rejecting the Self / 4. Denial of the Self
6475
|
In perception, the self is just a logical fiction demanded by grammar
|
17. Mind and Body / B. Behaviourism / 4. Behaviourism Critique
5778
|
If we object to all data which is 'introspective' we will cease to believe in toothaches
|
6433
|
Behaviourists struggle to explain memory and imagination, because they won't admit images
|
17. Mind and Body / D. Property Dualism / 3. Property Dualism
5779
|
There are distinct sets of psychological and physical causal laws
|
17. Mind and Body / E. Mind as Physical / 2. Reduction of Mind
7550
|
We could probably, in principle, infer minds from brains, and brains from minds
|
18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality
5369
|
It is rational to believe in reality, despite the lack of demonstrative reasons for it
|
18. Thought / A. Modes of Thought / 6. Judgement / a. Nature of Judgement
5375
|
Knowledge of truths applies to judgements; knowledge by acquaintance applies to sensations and things
|
21711
|
Russell's 'multiple relations' theory says beliefs attach to ingredients, not to propositions [Linsky,B]
|
5427
|
Truth is when a mental state corresponds to a complex unity of external constituents
|
18. Thought / A. Modes of Thought / 6. Judgement / b. Error
21542
|
Do incorrect judgements have non-existent, or mental, or external objects?
|
22306
|
To explain false belief we should take belief as relating to a proposition's parts, not to the whole thing
|
5425
|
In order to explain falsehood, a belief must involve several terms, not two
|
6097
|
The theory of error seems to need the existence of the non-existent
|
6443
|
Surprise is a criterion of error
|
18. Thought / C. Content / 1. Content
21541
|
The complexity of the content correlates with the complexity of the object
|
18. Thought / C. Content / 6. Broad Content
7531
|
We don't assert private thoughts; the objects are part of what we assert
|
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
5384
|
A universal of which we are aware is called a 'concept'
|
18. Thought / E. Abstraction / 7. Abstracta by Equivalence
10583
|
Abstraction principles identify a common property, which is some third term with the right relation
|
10582
|
The principle of Abstraction says a symmetrical, transitive relation analyses into an identity
|
10584
|
A certain type of property occurs if and only if there is an equivalence relation
|
19. Language / A. Nature of Meaning / 1. Meaning
6112
|
Meaning takes many different forms, depending on different logical types
|
19. Language / A. Nature of Meaning / 5. Meaning as Verification
13468
|
Russell started philosophy of language, by declaring some plausible sentences to be meaningless [Hart,WD]
|
5388
|
Every understood proposition is composed of constituents with which we are acquainted
|
6427
|
Unverifiable propositions about the remote past are still either true or false
|
19. Language / B. Reference / 1. Reference theories
4567
|
Russell argued with great plausibility that we rarely, if ever, refer with our words [Cooper,DE]
|
19. Language / B. Reference / 2. Denoting
16385
|
A definite description 'denotes' an entity if it fits the description uniquely [Recanati]
|
5810
|
Referring is not denoting, and Russell ignores the referential use of definite descriptions [Donnellan]
|
5774
|
Denoting phrases are meaningless, but guarantee meaning for propositions
|
5775
|
In 'Scott is the author of Waverley', denotation is identical, but meaning is different
|
19. Language / B. Reference / 4. Descriptive Reference / a. Sense and reference
16987
|
By eliminating descriptions from primitive notation, Russell seems to reject 'sense' [Kripke]
|
19. Language / B. Reference / 4. Descriptive Reference / b. Reference by description
5387
|
It is pure chance which descriptions in a person's mind make a name apply to an individual
|
19. Language / B. Reference / 5. Speaker's Reference
4570
|
Russell assumes that expressions refer, but actually speakers refer by using expressions [Cooper,DE]
|
19. Language / C. Assigning Meanings / 3. Predicates
9022
|
Russell uses 'propositional function' to refer to both predicates and to attributes [Quine]
|
19. Language / C. Assigning Meanings / 5. Fregean Semantics
16349
|
Russell rejected sense/reference, because it made direct acquaintance with things impossible [Recanati]
|
7313
|
'Sense' is superfluous (rather than incoherent) [Miller,A]
|
19. Language / C. Assigning Meanings / 6. Truth-Conditions Semantics
7767
|
The theory of definite descriptions aims at finding correct truth conditions [Lycan]
|
19. Language / C. Assigning Meanings / 9. Indexical Semantics
21550
|
Science reduces indexicals to a minimum, but they can never be eliminated from empirical matters
|
19. Language / D. Propositions / 1. Propositions
14110
|
Proposition contain entities indicated by words, rather than the words themselves
|
21543
|
If p is false, then believing not-p is knowing a truth, so negative propositions must exist
|
6091
|
Propositions don't name facts, because each fact corresponds to a proposition and its negation
|
5781
|
Our important beliefs all, if put into words, take the form of propositions
|
5782
|
A proposition expressed in words is a 'word-proposition', and one of images an 'image-proposition'
|
5776
|
A proposition is what we believe when we believe truly or falsely
|
14451
|
Propositions are mainly verbal expressions of true or false, and perhaps also symbolic thoughts
|
19. Language / D. Propositions / 3. Concrete Propositions
19164
|
If propositions are facts, then false and true propositions are indistinguishable [Davidson]
|
21726
|
In graspable propositions the constituents are real entities of acquaintance
|
21702
|
In 1918 still believes in nonlinguistic analogues of sentences, but he now calls them 'facts' [Quine]
|
19. Language / D. Propositions / 4. Mental Propositions
22307
|
Propositions don't name facts, because two opposed propositions can match one fact
|
6435
|
You can believe the meaning of a sentence without thinking of the words
|
19. Language / D. Propositions / 5. Unity of Propositions
19157
|
Russell said the proposition must explain its own unity - or else objective truth is impossible [Davidson]
|
14111
|
A proposition is a unity, and analysis destroys it
|
19. Language / D. Propositions / 6. Propositions Critique
7534
|
In 1906, Russell decided that propositions did not, after all, exist [Monk]
|
21724
|
The main aim of the multiple relations theory of judgement was to dispense with propositions [Linsky,B]
|
6094
|
An inventory of the world does not need to include propositions
|
6096
|
I no longer believe in propositions, especially concerning falsehoods
|
21712
|
I know longer believe in shadowy things like 'that today is Wednesday' when it is actually Tuesday
|
19. Language / F. Communication / 3. Denial
16491
|
If we define 'this is not blue' as disbelief in 'this is blue', we eliminate 'not' as an ingredient of facts
|
19. Language / F. Communication / 4. Private Language
6093
|
The names in a logically perfect language would be private, and could not be shared
|
20. Action / C. Motives for Action / 3. Acting on Reason / b. Intellectualism
16478
|
A mother cat is paralysed if equidistant between two needy kittens
|
22. Metaethics / A. Value / 2. Values / f. Love
21746
|
Unlike hate, all desires can be satisfied by love
|
22. Metaethics / B. The Good / 1. Goodness / b. Types of good
21747
|
Goodness is a combination of love and knowledge
|
22. Metaethics / B. The Good / 2. Happiness / d. Routes to happiness
21743
|
In wartime, happiness is hating the enemy, because it gives the war a purpose
|
20180
|
A happy and joyous life must largely be a quiet life
|
22. Metaethics / C. Ethics Foundations / 1. Nature of Ethics / d. Ethical theory
21740
|
I doubt whether ethics is part of philosophy
|
22. Metaethics / C. Ethics Foundations / 2. Source of Ethics / e. Human nature
23154
|
We divide mankind into friend and foe, and cooperate with one and compete with the other
|
22. Metaethics / C. Ethics Foundations / 2. Source of Ethics / h. Expressivism
21741
|
'You ought to do p' primarily has emotional content, expressing approval
|
23. Ethics / C. Virtue Theory / 1. Virtue Theory / b. Basis of virtue
21742
|
Originally virtue was obedience, to gods, government, or custom
|
23. Ethics / C. Virtue Theory / 3. Virtues / h. Respect
21517
|
Individuals need creativity, reverence for others, and self-respect
|
23. Ethics / D. Deontological Ethics / 4. Categorical Imperative
21745
|
Act so as to produce harmonious rather than discordant desires
|
23. Ethics / E. Utilitarianism / 2. Ideal of Pleasure
5398
|
Judgements of usefulness depend on judgements of value
|
23. Ethics / F. Existentialism / 4. Boredom
20177
|
Boredom always involves not being fully occupied
|
20178
|
Life is now more interesting, but boredom is more frightening
|
20179
|
Happiness involves enduring boredom, and the young should be taught this
|
20176
|
Boredom is an increasingly strong motivating power
|
24. Political Theory / A. Basis of a State / 1. A People / c. A unified people
23152
|
Increasingly war expands communities, and unifies them through fear
|
23153
|
Gradually loyalty to a creed increased, which could even outweigh nationality
|
23155
|
In early societies the leaders needed cohesion, but the rest just had to obey
|
24. Political Theory / A. Basis of a State / 2. Population / b. State population
23156
|
The economic and political advantages of great size seem to have no upper limit
|
24. Political Theory / B. Nature of a State / 1. Purpose of a State
23157
|
Government has a negative purpose, to prevent trouble, and a positive aim of realising our desires
|
24. Political Theory / C. Ruling a State / 2. Leaders / b. Monarchy
23151
|
A monarch is known to everyone in the group, and can thus unite large groups
|
24. Political Theory / C. Ruling a State / 4. Changing the State / b. Devolution
21522
|
Democracy is inadequate without a great deal of devolution
|
21523
|
We would not want UK affairs to be settled by a world parliament
|
23167
|
Power should be with smaller bodies, as long as it doesn't restrict central powers
|
24. Political Theory / D. Ideologies / 2. Anarchism
21521
|
Anarchy does not maximise liberty
|
23163
|
In an anarchy universities, research, books, and even seaside holidays, would be impossible
|
23168
|
A state is essential, to control greedy or predatory impulses
|
24. Political Theory / D. Ideologies / 5. Democracy / c. Direct democracy
21528
|
Groups should be autonomous, with a neutral authority as arbitrator
|
24. Political Theory / D. Ideologies / 5. Democracy / f. Against democracy
21526
|
Unfortunately ordinary voters can't detect insincerity
|
21527
|
On every new question the majority is always wrong at first
|
23166
|
In democracy we are more aware of being governed than of our tiny share in government
|
23169
|
Democratic institutions become impossible in a fanatical democracy
|
24. Political Theory / D. Ideologies / 6. Liberalism / a. Liberalism basics
23170
|
Liberal opinions are tentative rather than dogmatic, and are always responsive to new evidence
|
23171
|
Empiricism is ethically superior, because dogmatism favours persecution and hatred
|
23172
|
Empiricist Liberalism is the only view for someone who favours scientific evidence and happiness
|
24. Political Theory / D. Ideologies / 8. Socialism
21525
|
When the state is the only employer, there is no refuge from the prejudices of other people
|
23160
|
Being a slave of society is hardly better than being a slave of a despot
|
23162
|
Managers are just as remote from workers under nationalisation as under capitalism
|
23165
|
Socialists say economic justice needs some state control of industries, and of foreign trade
|
24. Political Theory / D. Ideologies / 11. Capitalism
21518
|
Men unite in pursuit of material things, and idealise greed as part of group loyalty
|
25. Social Practice / A. Freedoms / 1. Slavery
23158
|
Slavery began the divorce between the work and the purposes of the worker
|
25. Social Practice / A. Freedoms / 5. Freedom of lifestyle
21519
|
We need security and liberty, and then encouragement of creativity
|
25. Social Practice / B. Equalities / 1. Grounds of equality
23161
|
Slaves can be just as equal as free people
|
25. Social Practice / B. Equalities / 4. Economic equality
23159
|
Scarce goods may be denied entirely, to avoid their unequal distribution
|
25. Social Practice / C. Rights / 4. Property rights
21524
|
The right to own land gives a legal right to a permanent income
|
25. Social Practice / D. Justice / 1. Basis of justice
23164
|
Modern justice is seen as equality, apart from modest extra rewards for exceptional desert
|
25. Social Practice / D. Justice / 3. Punishment / d. Reform of offenders
21744
|
Legally curbing people's desires is inferior to improving their desires
|
26. Natural Theory / C. Causation / 7. Eliminating causation
14172
|
Moments and points seem to imply other moments and points, but don't cause them
|
14175
|
We can drop 'cause', and just make inferences between facts
|
4396
|
The law of causality is a source of confusion, and should be dropped from philosophy
|
8376
|
If causes are contiguous with events, only the last bit is relevant, or the event's timing is baffling
|
26. Natural Theory / C. Causation / 9. General Causation / a. Constant conjunction
8380
|
Striking a match causes its igniting, even if it sometimes doesn't work
|
26. Natural Theory / D. Laws of Nature / 1. Laws of Nature
17633
|
The law of gravity has many consequences beyond its grounding observations
|
26. Natural Theory / D. Laws of Nature / 5. Laws from Universals
8379
|
In causal laws, 'events' must recur, so they have to be universals, not particulars
|
26. Natural Theory / D. Laws of Nature / 6. Laws as Numerical
8381
|
The constancy of scientific laws rests on differential equations, not on cause and effect
|
26. Natural Theory / D. Laws of Nature / 11. Against Laws of Nature
14174
|
The laws of motion and gravitation are just parts of the definition of a kind of matter
|
5393
|
We can't know that our laws are exceptionless, or even that there are any laws
|
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
14168
|
Occupying a place and change are prior to motion, so motion is just occupying places at continuous times
|
4786
|
Russell's 'at-at' theory says motion is to be at the intervening points at the intervening instants [Psillos]
|
27. Natural Reality / A. Classical Physics / 1. Mechanics / c. Forces
14171
|
Force is supposed to cause acceleration, but acceleration is a mathematical fiction
|
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
6470
|
Matter is the limit of appearances as distance from the object diminishes
|
7551
|
Matter is a logical construction
|
7547
|
Matter requires a division into time-corpuscles as well as space-corpuscles
|
21706
|
At first matter is basic and known by sense-data; later Russell says matter is constructed [Linsky,B]
|
27. Natural Reality / C. Space / 2. Space
6468
|
There is 'private space', and there is also the 'space of perspectives'
|
7552
|
Six dimensions are needed for a particular, three within its own space, and three to locate that space
|
27. Natural Reality / C. Space / 3. Points in Space
14160
|
Space is the extension of 'point', and aggregates of points seem necessary for geometry
|
27. Natural Reality / D. Time / 2. Passage of Time / a. Experience of time
21581
|
We never experience times, but only succession of events
|
27. Natural Reality / D. Time / 3. Parts of Time / b. Instants
14156
|
Mathematicians don't distinguish between instants of time and points on a line
|
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
22891
|
We could be aware of time if senses briefly vibrated, extending their experience of movement [Bardon]
|
27. Natural Reality / E. Cosmology / 1. Cosmology
14169
|
The 'universe' can mean what exists now, what always has or will exist
|
28. God / A. Divine Nature / 6. Divine Morality / b. Euthyphro question
2609
|
If God's decrees are good, and this is not a mere tautology, then goodness is separate from God's decrees
|
28. God / B. Proving God / 2. Proofs of Reason / b. Ontological Proof critique
5773
|
The ontological argument begins with an unproven claim that 'there exists an x..'
|
6119
|
You can discuss 'God exists', so 'God' is a description, not a name
|
29. Religion / D. Religious Issues / 2. Immortality / d. Heaven
21520
|
That our heaven is a dull place reflects the misery of excessive work in life
|