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All the ideas for 'The Philosophy of Logic', 'Action' and 'Introduction to the Philosophy of Mathematics'

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39 ideas

4. Formal Logic / E. Nonclassical Logics / 2. Intuitionist Logic
Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan]
Rejecting double negation elimination undermines reductio proofs [Colyvan]
5. Theory of Logic / D. Assumptions for Logic / 2. Excluded Middle
Excluded middle says P or not-P; bivalence says P is either true or false [Colyvan]
5. Theory of Logic / J. Model Theory in Logic / 3. Löwenheim-Skolem Theorems
Löwenheim proved his result for a first-order sentence, and Skolem generalised it [Colyvan]
5. Theory of Logic / K. Features of Logics / 1. Axiomatisation
Axioms are 'categorical' if all of their models are isomorphic [Colyvan]
6. Mathematics / A. Nature of Mathematics / 3. Nature of Numbers / e. Ordinal numbers
Ordinal numbers represent order relations [Colyvan]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / a. The Infinite
Intuitionists only accept a few safe infinities [Colyvan]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / i. Cardinal infinity
Very large sets should be studied in an 'if-then' spirit [Putnam]
6. Mathematics / A. Nature of Mathematics / 5. The Infinite / j. Infinite divisibility
Infinitesimals were sometimes zero, and sometimes close to zero [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 1. Foundations for Mathematics
Reducing real numbers to rationals suggested arithmetic as the foundation of maths [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 4. Axioms for Number / f. Mathematical induction
Transfinite induction moves from all cases, up to the limit ordinal [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 6. Mathematics as Set Theory / a. Mathematics is set theory
Most mathematical proofs are using set theory, but without saying so [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Structuralism say only 'up to isomorphism' matters because that is all there is to it [Colyvan]
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / e. Structuralism critique
If 'in re' structures relies on the world, does the world contain rich enough structures? [Colyvan]
6. Mathematics / C. Sources of Mathematics / 4. Mathematical Empiricism / b. Indispensability of mathematics
Indispensability strongly supports predicative sets, and somewhat supports impredicative sets [Putnam]
We must quantify over numbers for science; but that commits us to their existence [Putnam]
14. Science / C. Induction / 6. Bayes's Theorem
Probability supports Bayesianism better as degrees of belief than as ratios of frequencies [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / e. Lawlike explanations
Mathematics can reveal structural similarities in diverse systems [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / f. Necessity in explanations
Mathematics can show why some surprising events have to occur [Colyvan]
14. Science / D. Explanation / 2. Types of Explanation / m. Explanation by proof
Proof by cases (by 'exhaustion') is said to be unexplanatory [Colyvan]
Reductio proofs do not seem to be very explanatory [Colyvan]
If inductive proofs hold because of the structure of natural numbers, they may explain theorems [Colyvan]
Can a proof that no one understands (of the four-colour theorem) really be a proof? [Colyvan]
15. Nature of Minds / C. Capacities of Minds / 5. Generalisation by mind
Mathematical generalisation is by extending a system, or by abstracting away from it [Colyvan]
20. Action / A. Definition of Action / 1. Action Theory
Actions include: the involuntary, the purposeful, the intentional, and the self-consciously autonomous [Wilson/Schpall]
20. Action / A. Definition of Action / 4. Action as Movement
Maybe bodily movements are not actions, but only part of an agent's action of moving [Wilson/Schpall]
Is the action the arm movement, the whole causal process, or just the trying to do it? [Wilson/Schpall]
20. Action / B. Preliminaries of Action / 1. Intention to Act / a. Nature of intentions
To be intentional, an action must succeed in the manner in which it was planned [Wilson/Schpall]
If someone believes they can control the lottery, and then wins, the relevant skill is missing [Wilson/Schpall]
We might intend two ways to acting, knowing only one of them can succeed [Wilson/Schpall]
20. Action / B. Preliminaries of Action / 1. Intention to Act / c. Reducing intentions
On one model, an intention is belief-desire states, and intentional actions relate to beliefs and desires [Wilson/Schpall]
20. Action / B. Preliminaries of Action / 1. Intention to Act / d. Group intentions
Groups may act for reasons held by none of the members, so maybe groups are agents [Wilson/Schpall]
If there are shared obligations and intentions, we may need a primitive notion of 'joint commitment' [Wilson/Schpall]
20. Action / C. Motives for Action / 2. Acting on Beliefs / b. Action cognitivism
Strong Cognitivism identifies an intention to act with a belief [Wilson/Schpall]
Weak Cognitivism says intentions are only partly constituted by a belief [Wilson/Schpall]
Strong Cognitivism implies a mode of 'practical' knowledge, not based on observation [Wilson/Schpall]
20. Action / C. Motives for Action / 3. Acting on Reason / b. Intellectualism
Maybe the explanation of an action is in the reasons that make it intelligible to the agent [Wilson/Schpall]
20. Action / C. Motives for Action / 3. Acting on Reason / c. Reasons as causes
It is generally assumed that reason explanations are causal [Wilson/Schpall]
Causalists allow purposive explanations, but then reduce the purpose to the action's cause [Wilson/Schpall]