Combining Philosophers

All the ideas for Chrysippus, Alfred Tarski and Henri Poincar

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145 ideas

1. Philosophy / A. Wisdom / 1. Nature of Wisdom
Wisdom for one instant is as good as wisdom for eternity [Chrysippus]
1. Philosophy / A. Wisdom / 2. Wise People
Wise men should try to participate in politics, since they are a good influence [Chrysippus, by Diog. Laertius]
1. Philosophy / D. Nature of Philosophy / 4. Divisions of Philosophy
Three branches of philosophy: first logic, second ethics, third physics (which ends with theology) [Chrysippus]
1. Philosophy / E. Nature of Metaphysics / 5. Metaphysics beyond Science
Some say metaphysics is a highly generalised empirical study of objects [Tarski]
1. Philosophy / F. Analytic Philosophy / 1. Nature of Analysis
Disputes that fail to use precise scientific terminology are all meaningless [Tarski]
2. Reason / B. Laws of Thought / 2. Sufficient Reason
Chrysippus said the uncaused is non-existent [Chrysippus, by Plutarch]
2. Reason / D. Definition / 1. Definitions
For a definition we need the words or concepts used, the rules, and the structure of the language [Tarski]
3. Truth / A. Truth Problems / 2. Defining Truth
In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski]
Tarski proved that truth cannot be defined from within a given theory [Tarski, by Halbach]
Tarski proved that any reasonably expressive language suffers from the liar paradox [Tarski, by Horsten]
'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless [Tarski]
Definitions of truth should not introduce a new version of the concept, but capture the old one [Tarski]
A definition of truth should be materially adequate and formally correct [Tarski]
A rigorous definition of truth is only possible in an exactly specified language [Tarski]
We may eventually need to split the word 'true' into several less ambiguous terms [Tarski]
3. Truth / B. Truthmakers / 10. Making Future Truths
The causes of future true events must exist now, so they will happen because of destiny [Chrysippus, by Cicero]
3. Truth / C. Correspondence Truth / 2. Correspondence to Facts
Graspable presentations are criteria of facts, and are molded according to their objects [Chrysippus, by Diog. Laertius]
3. Truth / C. Correspondence Truth / 3. Correspondence Truth critique
How could you ever know that the presentation is similar to the object? [Sext.Empiricus on Chrysippus]
Tarski's Theorem renders any precise version of correspondence impossible [Tarski, by Halbach]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
Scheme (T) is not a definition of truth [Tarski]
Tarski gave up on the essence of truth, and asked how truth is used, or how it functions [Tarski, by Horsten]
Tarski did not just aim at a definition; he also offered an adequacy criterion for any truth definition [Tarski, by Halbach]
Tarski enumerates cases of truth, so it can't be applied to new words or languages [Davidson on Tarski]
Tarski define truths by giving the extension of the predicate, rather than the meaning [Davidson on Tarski]
Tarski made truth relative, by only defining truth within some given artificial language [Tarski, by O'Grady]
Tarski has to avoid stating how truths relate to states of affairs [Kirkham on Tarski]
Tarskian semantics says that a sentence is true iff it is satisfied by every sequence [Tarski, by Hossack]
'"It is snowing" is true if and only if it is snowing' is a partial definition of the concept of truth [Tarski]
It is convenient to attach 'true' to sentences, and hence the language must be specified [Tarski]
In the classical concept of truth, 'snow is white' is true if snow is white [Tarski]
Use 'true' so that all T-sentences can be asserted, and the definition will then be 'adequate' [Tarski]
Each interpreted T-sentence is a partial definition of truth; the whole definition is their conjunction [Tarski]
We don't give conditions for asserting 'snow is white'; just that assertion implies 'snow is white' is true [Tarski]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
Truth only applies to closed formulas, but we need satisfaction of open formulas to define it [Burgess on Tarski]
Tarski uses sentential functions; truly assigning the objects to variables is what satisfies them [Tarski, by Rumfitt]
We can define the truth predicate using 'true of' (satisfaction) for variables and some objects [Tarski, by Horsten]
For physicalism, reduce truth to satisfaction, then define satisfaction as physical-plus-logic [Tarski, by Kirkham]
Insight: don't use truth, use a property which can be compositional in complex quantified sentence [Tarski, by Kirkham]
Tarski gave axioms for satisfaction, then derived its explicit definition, which led to defining truth [Tarski, by Davidson]
The best truth definition involves other semantic notions, like satisfaction (relating terms and objects) [Tarski]
Specify satisfaction for simple sentences, then compounds; true sentences are satisfied by all objects [Tarski]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / c. Meta-language for truth
We can't use a semantically closed language, or ditch our logic, so a meta-language is needed [Tarski]
The metalanguage must contain the object language, logic, and defined semantics [Tarski]
3. Truth / F. Semantic Truth / 2. Semantic Truth
Tarski defined truth for particular languages, but didn't define it across languages [Davidson on Tarski]
Tarski didn't capture the notion of an adequate truth definition, as Convention T won't prove non-contradiction [Halbach on Tarski]
Tarski says that his semantic theory of truth is completely neutral about all metaphysics [Tarski, by Haack]
Physicalists should explain reference nonsemantically, rather than getting rid of it [Tarski, by Field,H]
A physicalist account must add primitive reference to Tarski's theory [Field,H on Tarski]
If listing equivalences is a reduction of truth, witchcraft is just a list of witch-victim pairs [Field,H on Tarski]
Tarski made truth respectable, by proving that it could be defined [Tarski, by Halbach]
Tarski had a theory of truth, and a theory of theories of truth [Tarski, by Read]
Tarski's 'truth' is a precise relation between the language and its semantics [Tarski, by Walicki]
Tarskian truth neglects the atomic sentences [Mulligan/Simons/Smith on Tarski]
3. Truth / G. Axiomatic Truth / 1. Axiomatic Truth
Tarski defined truth, but an axiomatisation can be extracted from his inductive clauses [Tarski, by Halbach]
Tarski's had the first axiomatic theory of truth that was minimally adequate [Tarski, by Horsten]
Tarski thought axiomatic truth was too contingent, and in danger of inconsistencies [Tarski, by Davidson]
We need an undefined term 'true' in the meta-language, specified by axioms [Tarski]
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Truth can't be eliminated from universal claims, or from particular unspecified claims [Tarski]
3. Truth / H. Deflationary Truth / 2. Deflationary Truth
Semantics is a very modest discipline which solves no real problems [Tarski]
4. Formal Logic / B. Propositional Logic PL / 1. Propositional Logic
Stoic propositional logic is like chemistry - how atoms make molecules, not the innards of atoms [Chrysippus, by Devlin]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
Chrysippus has five obvious 'indemonstrables' of reasoning [Chrysippus, by Diog. Laertius]
4. Formal Logic / B. Propositional Logic PL / 3. Truth Tables
Truth tables give prior conditions for logic, but are outside the system, and not definitions [Tarski]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Set theory and logic are fairy tales, but still worth studying [Tarski]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
There is no clear boundary between the logical and the non-logical [Tarski]
5. Theory of Logic / A. Overview of Logic / 6. Classical Logic
A language: primitive terms, then definition rules, then sentences, then axioms, and finally inference rules [Tarski]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Split out the logical vocabulary, make an assignment to the rest. It's logical if premises and conclusion match [Tarski, by Rumfitt]
5. Theory of Logic / B. Logical Consequence / 4. Semantic Consequence |=
Logical consequence is when in any model in which the premises are true, the conclusion is true [Tarski, by Beall/Restall]
Logical consequence: true premises give true conclusions under all interpretations [Tarski, by Hodges,W]
X follows from sentences K iff every model of K also models X [Tarski]
5. Theory of Logic / B. Logical Consequence / 5. Modus Ponens
Modus ponens is one of five inference rules identified by the Stoics [Chrysippus, by Devlin]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Every proposition is either true or false [Chrysippus, by Cicero]
The truth definition proves semantic contradiction and excluded middle laws (not the logic laws) [Tarski]
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Identity is invariant under arbitrary permutations, so it seems to be a logical term [Tarski, by McGee]
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
A name denotes an object if the object satisfies a particular sentential function [Tarski]
5. Theory of Logic / I. Semantics of Logic / 1. Semantics of Logic
Tarski built a compositional semantics for predicate logic, from dependent satisfactions [Tarski, by McGee]
Tarksi invented the first semantics for predicate logic, using this conception of truth [Tarski, by Kirkham]
Semantics is the concepts of connections of language to reality, such as denotation, definition and truth [Tarski]
A language containing its own semantics is inconsistent - but we can use a second language [Tarski]
5. Theory of Logic / I. Semantics of Logic / 4. Satisfaction
A sentence is satisfied when we can assert the sentence when the variables are assigned [Tarski]
Satisfaction is the easiest semantical concept to define, and the others will reduce to it [Tarski]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
A 'model' is a sequence of objects which satisfies a complete set of sentential functions [Tarski]
The object language/ metalanguage distinction is the basis of model theory [Tarski, by Halbach]
5. Theory of Logic / K. Features of Logics / 2. Consistency
Using the definition of truth, we can prove theories consistent within sound logics [Tarski]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
Tarski avoids the Liar Paradox, because truth cannot be asserted within the object language [Tarski, by Fisher]
The Liar makes us assert a false sentence, so it must be taken seriously [Tarski]
6. Mathematics / A. Nature of Mathematics / 2. Geometry
One geometry cannot be more true than another [Poincaré]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
Poincaré rejected the actual infinite, claiming definitions gave apparent infinity to finite objects [Poincaré, by Lavine]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Tarski improved Hilbert's geometry axioms, and without set-theory [Tarski, by Feferman/Feferman]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Mathematicians do not study objects, but relations between objects [Poincaré]
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Tarski's theory of truth shifted the approach away from syntax, to set theory and semantics [Feferman/Feferman on Tarski]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / a. Constructivism
Convention, yes! Arbitrary, no! [Poincaré, by Putnam]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
Avoid non-predicative classifications and definitions [Poincaré]
7. Existence / A. Nature of Existence / 6. Criterion for Existence
Chrysippus says action is the criterion for existence, which must be physical [Chrysippus, by Tieleman]
7. Existence / D. Theories of Reality / 8. Facts / b. Types of fact
There are simple and complex facts; the latter depend on further facts [Chrysippus, by Cicero]
7. Existence / E. Categories / 3. Proposed Categories
Stoics categories are Substrate, Quality, Disposition, and Relation [Chrysippus, by Pasnau]
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
I am a deeply convinced nominalist [Tarski]
9. Objects / B. Unity of Objects / 3. Unity Problems / b. Cat and its tail
Dion and Theon coexist, but Theon lacks a foot. If Dion loses a foot, he ousts Theon? [Chrysippus, by Philo of Alexandria]
9. Objects / E. Objects over Time / 2. Objects that Change
Change of matter doesn't destroy identity - in Dion and Theon change is a condition of identity [Chrysippus, by Long/Sedley]
15. Nature of Minds / A. Nature of Mind / 7. Animal Minds
Dogs show reason in decisions made by elimination [Chrysippus, by Sext.Empiricus]
16. Persons / F. Free Will / 4. For Free Will
Chrysippus allows evil to say it is fated, or even that it is rational and natural [Plutarch on Chrysippus]
16. Persons / F. Free Will / 5. Against Free Will
A swerve in the atoms would be unnatural, like scales settling differently for no reason [Chrysippus, by Plutarch]
16. Persons / F. Free Will / 6. Determinism / a. Determinism
Everything is fated, either by continuous causes or by a supreme rational principle [Chrysippus, by Diog. Laertius]
Chrysippus is wrong to believe in non-occurring future possibilities if he is a fatalist [Plutarch on Chrysippus]
16. Persons / F. Free Will / 6. Determinism / b. Fate
The Lazy Argument responds to fate with 'why bother?', but the bothering is also fated [Chrysippus, by Cicero]
Fate is an eternal and fixed chain of causal events [Chrysippus]
When we say events are fated by antecedent causes, do we mean principal or auxiliary causes? [Chrysippus]
16. Persons / F. Free Will / 7. Compatibilism
Destiny is only a predisposing cause, not a sufficient cause [Chrysippus, by Plutarch]
19. Language / D. Propositions / 1. Propositions
A proposition is what can be asserted or denied on its own [Chrysippus]
19. Language / E. Analyticity / 1. Analytic Propositions
Sentences are 'analytical' if every sequence of objects models them [Tarski]
20. Action / B. Preliminaries of Action / 2. Willed Action / d. Weakness of will
Passions are judgements; greed thinks money is honorable, and likewise drinking and lust [Chrysippus, by Diog. Laertius]
20. Action / C. Motives for Action / 5. Action Dilemmas / c. Omissions
The highest degree of morality performs all that is appropriate, omitting nothing [Chrysippus]
21. Aesthetics / A. Aesthetic Experience / 3. Taste
Taste is the capacity to judge an object or representation which is thought to be beautiful [Tarski, by Schellekens]
21. Aesthetics / C. Artistic Issues / 7. Art and Morality
Stoics say that beauty and goodness are equivalent and linked [Chrysippus, by Diog. Laertius]
22. Metaethics / A. Ethics Foundations / 1. Nature of Ethics / g. Moral responsibility
Fate initiates general causes, but individual wills and characters dictate what we do [Chrysippus]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / e. Human nature
Human purpose is to contemplate and imitate the cosmos [Chrysippus]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / j. Ethics by convention
Stoics say justice is a part of nature, not just an invented principle [Chrysippus, by Diog. Laertius]
22. Metaethics / A. Ethics Foundations / 2. Source of Ethics / k. Ethics from nature
Only nature is available to guide action and virtue [Chrysippus]
22. Metaethics / B. Value / 1. Nature of Value / f. Ultimate value
Live in agreement, according to experience of natural events [Chrysippus]
22. Metaethics / C. The Good / 1. Goodness / d. Good as virtue
Living happily is nothing but living virtuously [Chrysippus, by Plutarch]
22. Metaethics / C. The Good / 1. Goodness / f. Good as pleasure
Pleasure is not the good, because there are disgraceful pleasures [Chrysippus, by Diog. Laertius]
Justice can be preserved if pleasure is a good, but not if it is the goal [Chrysippus, by Plutarch]
22. Metaethics / C. The Good / 3. Pleasure / c. Value of pleasure
There are shameful pleasures, and nothing shameful is good, so pleasure is not a good [Chrysippus, by Diog. Laertius]
23. Ethics / A. Egoism / 2. Hedonism
People need nothing except corn and water [Chrysippus, by Plutarch]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / a. Nature of virtue
All virtue is good, but not always praised (as in not lusting after someone ugly) [Chrysippus]
23. Ethics / C. Virtue Theory / 1. Virtue Theory / b. Basis of virtue
Chrysippus says virtue can be lost (though Cleanthes says it is too secure for that) [Chrysippus, by Diog. Laertius]
Chrysippus says nothing is blameworthy, as everything conforms with the best nature [Chrysippus, by Plutarch]
24. Political Theory / A. Basis of a State / 1. A People / b. The natural life
Rational animals begin uncorrupted, but externals and companions are bad influences [Chrysippus, by Diog. Laertius]
25. Social Practice / D. Justice / 2. The Law / c. Natural law
Justice, the law, and right reason are natural and not conventional [Chrysippus, by Diog. Laertius]
25. Social Practice / F. Life Issues / 6. Animal Rights
We don't have obligations to animals as they aren't like us [Chrysippus, by Diog. Laertius]
Justice is irrelevant to animals, because they are too unlike us [Chrysippus, by Diog. Laertius]
26. Natural Theory / A. Speculations on Nature / 2. Natural Purpose / a. Final purpose
Covers are for shields, and sheaths for swords; likewise, all in the cosmos is for some other thing [Chrysippus]
26. Natural Theory / A. Speculations on Nature / 6. Early Matter Theories / f. Ancient elements
The later Stoics identified the logos with an air-fire compound, called 'pneuma' [Chrysippus, by Long]
Fire is a separate element, not formed with others (as was previously believed) [Chrysippus, by Stobaeus]
Stoics say earth, air, fire and water are the primary elements [Chrysippus, by Plutarch]
26. Natural Theory / D. Laws of Nature / 11. Against Laws of Nature
The aim of science is just to create a comprehensive, elegant language to describe brute facts [Poincaré, by Harré]
27. Natural Reality / D. Time / 1. Nature of Time / h. Presentism
The past and the future subsist, but only the present exists [Chrysippus, by Plutarch]
27. Natural Reality / D. Time / 3. Parts of Time / e. Present moment
The present does not exist, so our immediate experience is actually part past and part future [Chrysippus, by Plutarch]
Time is continous and infinitely divisible, so there cannot be a wholly present time [Chrysippus, by Stobaeus]
28. God / A. Divine Nature / 3. Divine Perfections
Stoics say that God the creator is the perfection of all animals [Chrysippus, by Diog. Laertius]
28. God / A. Divine Nature / 6. Divine Morality / a. Divine morality
The origin of justice can only be in Zeus, and in nature [Chrysippus]
28. God / A. Divine Nature / 6. Divine Morality / d. God decrees morality
Stoics teach that law is identical with right reason, which is the will of Zeus [Chrysippus, by Diog. Laertius]
The source of all justice is Zeus and the universal nature [Chrysippus]
29. Religion / B. Monotheistic Religion / 1. Monotheistic Religion
Stoics teach that God is a unity, variously known as Mind, or Fate, or Jupiter [Chrysippus, by Diog. Laertius]
29. Religion / D. Religious Issues / 2. Immortality / b. Soul
Death can't separate soul from body, because incorporeal soul can't unite with body [Chrysippus]
29. Religion / D. Religious Issues / 3. Problem of Evil / d. Natural Evil
There is a rationale in terrible disasters; they are useful to the whole, and make good possible [Chrysippus]