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All the ideas for 'works', 'Apprehension: reason in absence of Rules' and 'Rationality and Logic'

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71 ideas

1. Philosophy / F. Analytic Philosophy / 6. Logical Analysis
Frege's logical approach dominates the analytical tradition [Hanna]
1. Philosophy / G. Scientific Philosophy / 3. Scientism
Scientism says most knowledge comes from the exact sciences [Hanna]
2. Reason / F. Fallacies / 1. Fallacy
'Affirming the consequent' fallacy: φ→ψ, ψ, so φ [Hanna]
'Denying the antecedent' fallacy: φ→ψ, ¬φ, so ¬ψ [Hanna]
We can list at least fourteen informal fallacies [Hanna]
2. Reason / F. Fallacies / 4. Circularity
Circular arguments are formally valid, though informally inadmissible [Hanna]
2. Reason / F. Fallacies / 5. Fallacy of Composition
Formally, composition and division fallacies occur in mereology [Hanna]
4. Formal Logic / F. Set Theory ST / 1. Set Theory
Trying to represent curves, we study arbitrary functions, leading to the ordinals, which produces set theory [Cantor, by Lavine]
4. Formal Logic / F. Set Theory ST / 2. Mechanics of Set Theory / c. Basic theorems of ST
Cantor's Theorem: for any set x, its power set P(x) has more members than x [Cantor, by Hart,WD]
Cantor proved that all sets have more subsets than they have members [Cantor, by Bostock]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / c. Unit (Singleton) Sets
If a set is 'a many thought of as one', beginners should protest against singleton sets [Cantor, by Lewis]
4. Formal Logic / F. Set Theory ST / 3. Types of Set / d. Infinite Sets
The continuum is the powerset of the integers, which moves up a level [Cantor, by Clegg]
Cantor showed that supposed contradictions in infinity were just a lack of clarity [Cantor, by Potter]
4. Formal Logic / F. Set Theory ST / 4. Axioms for Sets / d. Axiom of Unions III
The Axiom of Union dates from 1899, and seems fairly obvious [Cantor, by Maddy]
4. Formal Logic / F. Set Theory ST / 5. Conceptions of Set / b. Combinatorial sets
Cantor's sets were just collections, but Dedekind's were containers [Cantor, by Oliver/Smiley]
5. Theory of Logic / A. Overview of Logic / 4. Pure Logic
Logic is explanatorily and ontologically dependent on rational animals [Hanna]
Logic is personal and variable, but it has a universal core [Hanna]
5. Theory of Logic / B. Logical Consequence / 1. Logical Consequence
Intensional consequence is based on the content of the concepts [Hanna]
5. Theory of Logic / K. Features of Logics / 8. Enumerability
There are infinite sets that are not enumerable [Cantor, by Smith,P]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / b. Cantor's paradox
Cantor's Paradox: the power set of the universe must be bigger than the universe, yet a subset of it [Cantor, by Hart,WD]
5. Theory of Logic / L. Paradox / 5. Paradoxes in Set Theory / e. Mirimanoff's paradox
The powerset of all the cardinal numbers is required to be greater than itself [Cantor, by Friend]
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Cantor named the third realm between the finite and the Absolute the 'transfinite' [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / b. Types of number
Cantor proved the points on a plane are in one-to-one correspondence to the points on a line [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / c. Priority of numbers
Cantor took the ordinal numbers to be primary [Cantor, by Tait]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / d. Natural numbers
Cantor presented the totality of natural numbers as finite, not infinite [Cantor, by Mayberry]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Cantor introduced the distinction between cardinals and ordinals [Cantor, by Tait]
Cantor showed that ordinals are more basic than cardinals [Cantor, by Dummett]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / f. Cardinal numbers
A cardinal is an abstraction, from the nature of a set's elements, and from their order [Cantor]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / g. Real numbers
Cantor tried to prove points on a line matched naturals or reals - but nothing in between [Cantor, by Lavine]
Cantor's diagonal argument proved you can't list all decimal numbers between 0 and 1 [Cantor, by Read]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / h. Reals from Cauchy
A real is associated with an infinite set of infinite Cauchy sequences of rationals [Cantor, by Lavine]
Irrational numbers are the limits of Cauchy sequences of rational numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Irrationals and the Dedekind Cut implied infinite classes, but they seemed to have logical difficulties [Cantor, by Lavine]
It was Cantor's diagonal argument which revealed infinities greater than that of the real numbers [Cantor, by Lavine]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / d. Actual infinite
Cantor proposes that there won't be a potential infinity if there is no actual infinity [Cantor, by Hart,WD]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / f. Uncountable infinities
The naturals won't map onto the reals, so there are different sizes of infinity [Cantor, by George/Velleman]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / g. Continuum Hypothesis
CH: An infinite set of reals corresponds 1-1 either to the naturals or to the reals [Cantor, by Koellner]
The Continuum Hypothesis says there are no sets between the natural numbers and reals [Cantor, by Shapiro]
Cantor: there is no size between naturals and reals, or between a set and its power set [Cantor, by Hart,WD]
Cantor's Continuum Hypothesis says there is a gap between the natural and the real numbers [Cantor, by Horsten]
Continuum Hypothesis: there are no sets between N and P(N) [Cantor, by Wolf,RS]
Continuum Hypothesis: no cardinal greater than aleph-null but less than cardinality of the continuum [Cantor, by Chihara]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / h. Ordinal infinity
Cantor's theory concerns collections which can be counted, using the ordinals [Cantor, by Lavine]
Cantor extended ordinals into the transfinite, and they can thus measure infinite cardinalities [Cantor, by Maddy]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Cardinality strictly concerns one-one correspondence, to test infinite sameness of size [Cantor, by Maddy]
6. Mathematics / B. Foundations for Mathematics / 5. Definitions of Number / e. Caesar problem
Property extensions outstrip objects, so shortage of objects caused the Caesar problem [Cantor, by Shapiro]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Pure mathematics is pure set theory [Cantor]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / a. Mathematical empiricism
Cantor says that maths originates only by abstraction from objects [Cantor, by Frege]
6. Mathematics / C. Sources of Mathematics / 6. Logicism / d. Logicism critique
Logicism struggles because there is no decent theory of analyticity [Hanna]
7. Existence / C. Structure of Existence / 5. Supervenience / b. Types of supervenience
Supervenience can add covariation, upward dependence, and nomological connection [Hanna]
10. Modality / A. Necessity / 2. Nature of Necessity
A sentence is necessary if it is true in a set of worlds, and nonfalse in the other worlds [Hanna]
10. Modality / A. Necessity / 5. Metaphysical Necessity
Metaphysical necessity can be 'weak' (same as logical) and 'strong' (based on essences) [Hanna]
10. Modality / A. Necessity / 6. Logical Necessity
Logical necessity is truth in all logically possible worlds, because of laws and concepts [Hanna]
10. Modality / A. Necessity / 7. Natural Necessity
Nomological necessity is truth in all logically possible worlds with our laws [Hanna]
12. Knowledge Sources / E. Direct Knowledge / 1. Common Sense
Apprehension is a complex intellect grasping the essence of a complex object [Holt,L]
12. Knowledge Sources / E. Direct Knowledge / 2. Intuition
Intuition includes apriority, clarity, modality, authority, fallibility and no inferences [Hanna]
Intuition is more like memory, imagination or understanding, than like perception [Hanna]
Intuition is only outside the 'space of reasons' if all reasons are inferential [Hanna]
14. Science / D. Explanation / 2. Types of Explanation / j. Explanations by reduction
Explanatory reduction is stronger than ontological reduction [Hanna]
15. Nature of Minds / C. Capacities of Minds / 2. Imagination
Imagination grasps abstracta, generates images, and has its own correctness conditions [Hanna]
18. Thought / A. Modes of Thought / 1. Thought
Should we take the 'depictivist' or the 'descriptivist/propositionalist' view of mental imagery? [Hanna]
18. Thought / A. Modes of Thought / 5. Rationality / a. Rationality
One tradition says talking is the essence of rationality; the other says the essence is logic [Hanna]
Kantian principled rationality is recognition of a priori universal truths [Hanna]
Humean Instrumental rationality is the capacity to seek contingent truths [Hanna]
Rational animals have a normative concept of necessity [Hanna]
Hegelian holistic rationality is the capacity to seek coherence [Hanna]
18. Thought / B. Mechanics of Thought / 1. Psychology
Most psychologists are now cognitivists [Hanna]
18. Thought / D. Concepts / 1. Concepts / a. Nature of concepts
Infinities expand the bounds of the conceivable; we explore concepts to explore conceivability [Cantor, by Friend]
18. Thought / E. Abstraction / 2. Abstracta by Selection
Cantor says (vaguely) that we abstract numbers from equal sized sets [Hart,WD on Cantor]
27. Natural Reality / C. Space / 3. Points in Space
Cantor proved that three dimensions have the same number of points as one dimension [Cantor, by Clegg]
28. God / A. Divine Nature / 2. Divine Nature
Only God is absolutely infinite [Cantor, by Hart,WD]