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All the ideas for 'Philosophy of Logic', 'Thinking About Mathematics' and 'The Upanishads'

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58 ideas

2. Reason / B. Laws of Thought / 3. Non-Contradiction
If you say that a contradiction is true, you change the meaning of 'not', and so change the subject [Quine]
3. Truth / F. Semantic Truth / 2. Semantic Truth
Talk of 'truth' when sentences are mentioned; it reminds us that reality is the point of sentences [Quine]
3. Truth / H. Deflationary Truth / 1. Redundant Truth
Truth is redundant for single sentences; we do better to simply speak the sentence [Quine]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
We can eliminate 'or' from our basic theory, by paraphrasing 'p or q' as 'not(not-p and not-q)' [Quine]
5. Theory of Logic / A. Overview of Logic / 1. Overview of Logic
My logical grammar has sentences by predication, then negation, conjunction, and existential quantification [Quine]
5. Theory of Logic / A. Overview of Logic / 3. Value of Logic
Maybe logical truth reflects reality, but in different ways in different languages [Quine]
5. Theory of Logic / A. Overview of Logic / 7. Second-Order Logic
Quine rejects second-order logic, saying that predicates refer to multiple objects [Quine, by Hodes]
Quantifying over predicates is treating them as names of entities [Quine]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle has three different definitions [Quine]
Intuitionists deny excluded middle, because it is committed to transcendent truth or objects [Shapiro]
5. Theory of Logic / D. Assumptions for Logic / 4. Identity in Logic
Quantification theory can still be proved complete if we add identity [Quine]
5. Theory of Logic / F. Referring in Logic / 1. Naming / f. Names eliminated
Names are not essential, because naming can be turned into predication [Quine]
5. Theory of Logic / G. Quantification / 1. Quantification
Universal quantification is widespread, but it is definable in terms of existential quantification [Quine]
5. Theory of Logic / G. Quantification / 4. Substitutional Quantification
You can't base quantification on substituting names for variables, if the irrationals cannot all be named [Quine]
Some quantifications could be false substitutionally and true objectually, because of nameless objects [Quine]
5. Theory of Logic / G. Quantification / 5. Second-Order Quantification
Putting a predicate letter in a quantifier is to make it the name of an entity [Quine]
5. Theory of Logic / I. Semantics of Logic / 3. Logical Truth
A sentence is logically true if all sentences with that grammatical structure are true [Quine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
The number 3 is presumably identical as a natural, an integer, a rational, a real, and complex [Shapiro]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
Cauchy gave a formal definition of a converging sequence. [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Categories are the best foundation for mathematics [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / f. Zermelo numbers
Two definitions of 3 in terms of sets disagree over whether 1 is a member of 3 [Shapiro]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Numbers do not exist independently; the essence of a number is its relations to other numbers [Shapiro]
A 'system' is related objects; a 'pattern' or 'structure' abstracts the pure relations from them [Shapiro]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Logicism seems to be a non-starter if (as is widely held) logic has no ontology of its own [Shapiro]
6. Mathematics / C. Sources of Mathematics / 7. Formalism
Term Formalism says mathematics is just about symbols - but real numbers have no names [Shapiro]
Game Formalism is just a matter of rules, like chess - but then why is it useful in science? [Shapiro]
Deductivism says mathematics is logical consequences of uninterpreted axioms [Shapiro]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / b. Intuitionism
Critics resent the way intuitionism cripples mathematics, but it allows new important distinctions [Shapiro]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / c. Conceptualism
Conceptualist are just realists or idealist or nominalists, depending on their view of concepts [Shapiro]
6. Mathematics / C. Sources of Mathematics / 10. Constructivism / d. Predicativism
'Impredicative' definitions refer to the thing being described [Shapiro]
8. Modes of Existence / B. Properties / 12. Denial of Properties
Predicates are not names; predicates are the other parties to predication [Quine]
9. Objects / A. Existence of Objects / 1. Physical Objects
A physical object is the four-dimensional material content of a portion of space-time [Quine]
9. Objects / E. Objects over Time / 4. Four-Dimensionalism
Four-d objects helps predication of what no longer exists, and quantification over items from different times [Quine]
10. Modality / B. Possibility / 8. Conditionals / b. Types of conditional
Some conditionals can be explained just by negation and conjunction: not(p and not-q) [Quine]
12. Knowledge Sources / C. Rationalism / 1. Rationalism
Rationalism tries to apply mathematical methodology to all of knowledge [Shapiro]
16. Persons / A. Concept of a Person / 3. Persons as Reasoners
Self is the rider, intellect the charioteer, mind the reins, and body the chariot [Anon (Upan)]
16. Persons / C. Self-Awareness / 2. Knowing the Self
We have an apparent and a true self; only the second one exists, and we must seek to know it [Anon (Upan)]
18. Thought / D. Concepts / 5. Concepts and Language / a. Concepts and language
Without speech we cannot know right/wrong, true/false, good/bad, or pleasant/unpleasant [Anon (Upan)]
19. Language / A. Nature of Meaning / 8. Synonymy
Single words are strongly synonymous if their interchange preserves truth [Quine]
19. Language / D. Propositions / 6. Propositions Critique
It makes no sense to say that two sentences express the same proposition [Quine]
There is no rule for separating the information from other features of sentences [Quine]
We can abandon propositions, and just talk of sentences and equivalence [Quine]
19. Language / F. Communication / 5. Pragmatics / a. Contextual meaning
A good way of explaining an expression is saying what conditions make its contexts true [Quine]
22. Metaethics / C. The Good / 3. Pleasure / c. Value of pleasure
The wise prefer good to pleasure; the foolish are drawn to pleasure by desire [Anon (Upan)]
25. Social Practice / E. Policies / 5. Education / c. Teaching
Let your teacher be a god to you [Anon (Upan)]
26. Natural Theory / B. Natural Kinds / 2. Defining Kinds
By knowing one piece of clay or gold, you know all of clay or gold [Anon (Upan)]
27. Natural Reality / E. Cosmology / 2. Eternal Universe
Originally there must have been just Existence, which could not come from non-existence [Anon (Upan)]
28. God / A. Divine Nature / 1. God
Brahma, supreme god and protector of the universe, arose from the ocean of existence [Anon (Upan)]
28. God / B. Proving God / 3. Proofs of Evidence / a. Cosmological Proof
Brahman is the Uncaused Cause [Anon (Upan)]
28. God / C. Attitudes to God / 2. Pantheism
Earth, food, fire, sun are all forms of Brahman [Anon (Upan)]
29. Religion / A. Polytheistic Religion / 3. Hinduism
The gods are not worshipped for their own sake, but for the sake of the Self [Anon (Upan)]
A man with desires is continually reborn, until his desires are stilled [Anon (Upan)]
Damayata - be self-controlled! Datta - be charitable! Dayadhwam - be compassionate! [Anon (Upan)]
Those ignorant of Atman return as animals or plants, according to their merits [Anon (Upan)]
29. Religion / D. Religious Issues / 1. Religious Commitment / a. Religious Belief
Charity and ritual observance distract from the highest good of religion [Anon (Upan)]
29. Religion / D. Religious Issues / 1. Religious Commitment / e. Fideism
Do not seek to know Brahman by arguments, for arguments are idle and vain [Anon (Upan)]
29. Religion / D. Religious Issues / 2. Immortality / b. Soul
The immortal in us is the part that never sleeps, and shapes our dreams [Anon (Upan)]
The immortal Self and the sad individual self are like two golden birds perched on one tree [Anon (Upan)]