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All the ideas for 'works', 'fragments/reports' and 'The Evolution of Logic'

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74 ideas

1. Philosophy / C. History of Philosophy / 4. Later European Philosophy / c. Eighteenth century philosophy
We are all post-Kantians, because he set the current agenda for philosophy [Hart,WD]
1. Philosophy / D. Nature of Philosophy / 1. Philosophy
Derrida focuses on other philosophers, rather than on science [Derrida]
1. Philosophy / D. Nature of Philosophy / 3. Philosophy Defined
Philosophy is just a linguistic display [Derrida]
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / d. Philosophy as puzzles
The problems are the monuments of philosophy [Hart,WD]
1. Philosophy / D. Nature of Philosophy / 5. Aims of Philosophy / e. Philosophy as reason
Philosophy aims to build foundations for thought [Derrida, by May]
1. Philosophy / D. Nature of Philosophy / 7. Despair over Philosophy
Philosophy is necessarily metaphorical, and its writing is aesthetic [Derrida]
1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
To study abstract problems, some knowledge of set theory is essential [Hart,WD]
1. Philosophy / H. Continental Philosophy / 3. Hermeneutics
Interpretations can be interpreted, so there is no original 'meaning' available [Derrida]
Hermeneutics blunts truth, by conforming it to the interpreter [Derrida, by Zimmermann,J]
Hermeneutics is hostile, trying to overcome the other person's difference [Derrida, by Zimmermann,J]
1. Philosophy / H. Continental Philosophy / 4. Linguistic Structuralism
Structuralism destroys awareness of dynamic meaning [Derrida]
1. Philosophy / H. Continental Philosophy / 6. Deconstruction
The idea of being as persistent presence, and meaning as conscious intelligibility, are self-destructive [Derrida, by Glendinning]
Sincerity can't be verified, so fiction infuses speech, and hence reality also [Derrida]
Sentences are contradictory, as they have opposite meanings in some contexts [Derrida]
We aim to explore the limits of expression (as in Mallarmé's poetry) [Derrida]
3. Truth / A. Truth Problems / 9. Rejecting Truth
Derrida says that all truth-talk is merely metaphor [Derrida, by Engel]
True thoughts are inaccessible, in the subconscious, prior to speech or writing [Derrida]
3. Truth / C. Correspondence Truth / 2. Correspondence to Facts
Tarski showed how we could have a correspondence theory of truth, without using 'facts' [Hart,WD]
3. Truth / F. Semantic Truth / 1. Tarski's Truth / b. Satisfaction and truth
Truth for sentences is satisfaction of formulae; for sentences, either all sequences satisfy it (true) or none do [Hart,WD]
3. Truth / F. Semantic Truth / 2. Semantic Truth
A first-order language has an infinity of T-sentences, which cannot add up to a definition of truth [Hart,WD]
4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / c. Derivation rules of PL
Conditional Proof: infer a conditional, if the consequent can be deduced from the antecedent [Hart,WD]
4. Formal Logic / C. Predicate Calculus PC / 2. Tools of Predicate Calculus / e. Existential quantifier ∃
∃y... is read as 'There exists an individual, call it y, such that...', and not 'There exists a y such that...' [Hart,WD]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Set theory articulates the concept of order (through relations) [Hart,WD]
Nowadays ZFC and NBG are the set theories; types are dead, and NF is only useful for the whole universe [Hart,WD]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / a. Symbols of ST
∈ relates across layers, while ⊆ relates within layers [Hart,WD]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / b. Empty (Null) Set
Without the empty set we could not form a∩b without checking that a and b meet [Hart,WD]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / i. Axiom of Foundation VIII
In the modern view, foundation is the heart of the way to do set theory [Hart,WD]
Foundation Axiom: an nonempty set has a member disjoint from it [Hart,WD]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / j. Axiom of Choice IX
With the Axiom of Choice every set can be well-ordered [Hart,WD]
We can choose from finite and evident sets, but not from infinite opaque ones [Hart,WD]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / o. Axiom of Constructibility V = L
If we accept that V=L, it seems to settle all the open questions of set theory [Hart,WD]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / d. Naïve logical sets
Naïve set theory has trouble with comprehension, the claim that every predicate has an extension [Hart,WD]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / e. Iterative sets
The iterative conception may not be necessary, and may have fixed points or infinitely descending chains [Hart,WD]
4. Formal Logic / F. Set Theory ST / 6. Ordering in Sets
'Well-ordering' must have a least member, so it does the natural numbers but not the integers [Hart,WD]
A partial ordering becomes 'total' if any two members of its field are comparable [Hart,WD]
A 'partial ordering' is irreflexive and transitive; the sets are ordered, but not the subsets [Hart,WD]
Von Neumann defines α<β as α∈β [Hart,WD]
4. Formal Logic / F. Set Theory ST / 8. Critique of Set Theory
Maybe sets should be rethought in terms of the even more basic categories [Hart,WD]
5. Theory of Logic / F. Referring in Logic / 1. Naming / b. Names as descriptive
Names have a subjective aspect, especially the role of our own name [Derrida]
'I' is the perfect name, because it denotes without description [Derrida]
5. Theory of Logic / F. Referring in Logic / 1. Naming / c. Names as referential
Even Kripke can't explain names; the word is the thing, and the thing is the word [Derrida]
5. Theory of Logic / G. Quantification / 3. Objectual Quantification
The universal quantifier can't really mean 'all', because there is no universal set [Hart,WD]
5. Theory of Logic / J. Model Theory in Logic / 1. Logical Models
Models are ways the world might be from a first-order point of view [Hart,WD]
Model theory studies how set theory can model sets of sentences [Hart,WD]
Model theory is mostly confined to first-order theories [Hart,WD]
Modern model theory begins with the proof of Los's Conjecture in 1962 [Hart,WD]
5. Theory of Logic / K. Features of Logics / 6. Compactness
First-order logic is 'compact': consequences of a set are consequences of a finite subset [Hart,WD]
5. Theory of Logic / L. Paradox / 4. Paradoxes in Logic / c. Berry's paradox
Berry's Paradox: we succeed in referring to a number, with a term which says we can't do that [Hart,WD]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / c. Burali-Forti's paradox
The Burali-Forti paradox is a crisis for Cantor's ordinals [Hart,WD]
5. Theory of Logic / L. Paradox / 6. Paradoxes in Language / a. The Liar paradox
The machinery used to solve the Liar can be rejigged to produce a new Liar [Hart,WD]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
The less-than relation < well-orders, and partially orders, and totally orders the ordinal numbers [Hart,WD]
There are at least as many infinite cardinals as transfinite ordinals (because they will map) [Hart,WD]
The axiom of infinity with separation gives a least limit ordinal ω [Hart,WD]
Von Neumann's ordinals generalise into the transfinite better, because Zermelo's ω is a singleton [Hart,WD]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
19th century arithmetization of analysis isolated the real numbers from geometry [Hart,WD]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
We can establish truths about infinite numbers by means of induction [Hart,WD]
6. Mathematics / B. Foundations for Mathematics / 3. Axioms for Geometry
Archimedes defined a straight line as the shortest distance between two points [Archimedes, by Leibniz]
Euclid has a unique parallel, spherical geometry has none, and saddle geometry has several [Hart,WD]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Mathematics makes existence claims, but philosophers usually say those are never analytic [Hart,WD]
7. Existence / C. Structure of Existence / 8. Stuff / a. Pure stuff
Mass words do not have plurals, or numerical adjectives, or use 'fewer' [Hart,WD]
12. Knowledge Sources / A. A Priori Knowledge / 2. Self-Evidence
Fregean self-evidence is an intrinsic property of basic truths, rules and definitions [Hart,WD]
12. Knowledge Sources / A. A Priori Knowledge / 11. Denying the A Priori
The failure of key assumptions in geometry, mereology and set theory throw doubt on the a priori [Hart,WD]
15. Nature of Minds / B. Features of Minds / 1. Consciousness / b. Essence of consciousness
Heidegger showed that passing time is the key to consciousness [Derrida]
18. Thought / A. Modes of Thought / 1. Thought
'Tacit theory' controls our thinking (which is why Freud is important) [Derrida]
18. Thought / D. Concepts / 3. Ontology of Concepts / c. Fregean concepts
The Fregean concept of GREEN is a function assigning true to green things, and false to the rest [Hart,WD]
19. Language / A. Nature of Meaning / 1. Meaning
Madness and instability ('the demonic hyperbole') lurks in all language [Derrida]
Meanings depend on differences and contrasts [Derrida]
For Aristotle all proper nouns must have a single sense, which is the purpose of language [Derrida]
Capacity for repetitions is the hallmark of language [Derrida]
The sign is only conceivable as a movement between elusive presences [Derrida]
Writing functions even if the sender or the receiver are absent [Derrida, by Glendinning]
19. Language / A. Nature of Meaning / 9. Ambiguity
'Dissemination' is opposed to polysemia, since that is irreducible, because of multiple understandings [Derrida, by Glendinning]
19. Language / A. Nature of Meaning / 10. Denial of Meanings
Words exist in 'spacing', so meanings are never synchronic except in writing [Derrida]
22. Metaethics / C. The Good / 1. Goodness / a. Form of the Good
The good is implicitly violent (against evil), so there is no pure good [Derrida]