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All the ideas for 'Laches', 'The Relation of Sense-Data to Physics' and 'Philosophy of Logic'

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34 ideas

1. Philosophy / A. Wisdom / 3. Wisdom Deflated
Don't assume that wisdom is the automatic consequence of old age [Plato]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / a. Tarski's truth definition
For scientific purposes there is a precise concept of 'true-in-L', using set theory [Putnam]
4. Formal Logic / A. Syllogistic Logic / 1. Aristotelian Logic
Modern notation frees us from Aristotle's restriction of only using two class-names in premises [Putnam]
4. Formal Logic / A. Syllogistic Logic / 2. Syllogistic Logic
The universal syllogism is now expressed as the transitivity of subclasses [Putnam]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / a. Symbols of PC
'⊃' ('if...then') is used with the definition 'Px ⊃ Qx' is short for '¬(Px & ¬Qx)' [Putnam]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / a. Types of set
In type theory, 'x ∈ y' is well defined only if x and y are of the appropriate type [Putnam]
5. Theory of Logic / A. Overview of Logic / 2. History of Logic
Before the late 19th century logic was trivialised by not dealing with relations [Putnam]
5. Theory of Logic / A. Overview of Logic / 5. First-Order Logic
Asserting first-order validity implicitly involves second-order reference to classes [Putnam]
5. Theory of Logic / C. Ontology of Logic / 1. Ontology of Logic
Unfashionably, I think logic has an empirical foundation [Putnam]
5. Theory of Logic / E. Structures of Logic / 5. Functions in Logic
We can identify functions with certain sets - or identify sets with certain functions [Putnam]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
Having a valid form doesn't ensure truth, as it may be meaningless [Putnam]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
Sets larger than the continuum should be studied in an 'if-then' spirit [Putnam]
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
Continuity is a sufficient criterion for the identity of a rock, but not for part of a smooth fluid [Russell]
8. Modes of Existence / E. Nominalism / 1. Nominalism / a. Nominalism
Nominalism only makes sense if it is materialist [Putnam]
9. Objects / A. Existence of Objects / 1. Physical Objects
Physical things are series of appearances whose matter obeys physical laws [Russell]
9. Objects / A. Existence of Objects / 2. Abstract Objects / b. Need for abstracta
Physics is full of non-physical entities, such as space-vectors [Putnam]
9. Objects / B. Unity of Objects / 2. Substance / e. Substance critique
We need not deny substance, but there seems no reason to assert it [Russell]
The assumption by physicists of permanent substance is not metaphysically legitimate [Russell]
11. Knowledge Aims / C. Knowing Reality / 2. Phenomenalism
Where possible, logical constructions are to be substituted for inferred entities [Russell]
12. Knowledge Sources / B. Perception / 4. Sense Data / b. Nature of sense-data
No sensibile is ever a datum to two people at once [Russell]
Russell held that we are aware of states of our own brain [Russell, by Robinson,H]
Sense-data are qualities devoid of subjectivity, which are the basis of science [Russell, by Deleuze/Guattari]
Sense-data are not mental, but are part of the subject-matter of physics [Russell]
Sense-data are objects, and do not contain the subject as part, the way beliefs do [Russell]
Sense-data are usually objects within the body, but are not part of the subject [Russell]
12. Knowledge Sources / B. Perception / 4. Sense Data / c. Unperceived sense-data
We do not know whether sense-data exist as objects when they are not data [Russell]
'Sensibilia' are identical to sense-data, without actually being data for any mind [Russell]
Ungiven sense-data can no more exist than unmarried husbands [Russell]
12. Knowledge Sources / B. Perception / 4. Sense Data / d. Sense-data problems
Individuating sense-data is difficult, because they divide when closely attended to [Russell]
Sense-data may be subjective, if closing our eyes can change them [Russell]
14. Science / A. Basis of Science / 4. Prediction
Most predictions are uninteresting, and are only sought in order to confirm a theory [Putnam]
23. Ethics / C. Virtue Theory / 3. Virtues / d. Courage
Being unafraid (perhaps through ignorance) and being brave are two different things [Plato]
27. Natural Reality / B. Modern Physics / 4. Standard Model / a. Concept of matter
Matter is the limit of appearances as distance from the object diminishes [Russell]
27. Natural Reality / C. Space / 2. Space
There is 'private space', and there is also the 'space of perspectives' [Russell]