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All the ideas for 'Conditionals', 'Quaestiones de anima' and 'Maths as a Science of Patterns'

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13 ideas

4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / e. Axioms of PL
Axioms are often affirmed simply because they produce results which have been accepted [Resnik]
     Full Idea: Many axioms have been proposed, not on the grounds that they can be directly known, but rather because they produce a desired body of previously recognised results.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], One.5.1)
     A reaction: This is the perennial problem with axioms - whether we start from them, or whether we deduce them after the event. There is nothing wrong with that, just as we might infer the existence of quarks because of their results.
6. Mathematics / A. Nature of Mathematics / 1. Mathematics
Mathematical realism says that maths exists, is largely true, and is independent of proofs [Resnik]
     Full Idea: Mathematical realism is the doctrine that mathematical objects exist, that much contemporary mathematics is true, and that the existence and truth in question is independent of our constructions, beliefs and proofs.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], Three.12.9)
     A reaction: As thus defined, I would call myself a mathematical realist, but everyone must hesitate a little at the word 'exist' and ask, how does it exist? What is it 'made of'? To say that it exists in the way that patterns exist strikes me as very helpful.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / a. Structuralism
Mathematical constants and quantifiers only exist as locations within structures or patterns [Resnik]
     Full Idea: In maths the primary subject-matter is not mathematical objects but structures in which they are arranged; our constants and quantifiers denote atoms, structureless points, or positions in structures; they have no identity outside a structure or pattern.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], Three.10.1)
     A reaction: This seems to me a very promising idea for the understanding of mathematics. All mathematicians acknowledge that the recognition of patterns is basic to the subject. Even animals recognise patterns. It is natural to invent a language of patterns.
Sets are positions in patterns [Resnik]
     Full Idea: On my view, sets are positions in certain patterns.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], Three.10.5)
     A reaction: I have always found the ontology of a 'set' puzzling, because they seem to depend on prior reasons why something is a member of a given set, which cannot always be random. It is hard to explain sets without mentioning properties.
6. Mathematics / B. Foundations for Mathematics / 7. Mathematical Structuralism / d. Platonist structuralism
Structuralism must explain why a triangle is a whole, and not a random set of points [Resnik]
     Full Idea: An objection is that structuralism fails to explain why certain mathematical patterns are unified wholes while others are not; for instance, some think that an ontological account of mathematics must explain why a triangle is not a 'random' set of points.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], Three.10.4)
     A reaction: This is an indication that we are not just saying that we recognise patterns in nature, but that we also 'see' various underlying characteristics of the patterns. The obvious suggestion is that we see meta-patterns.
There are too many mathematical objects for them all to be mental or physical [Resnik]
     Full Idea: If we take mathematics at its word, there are too many mathematical objects for it to be plausible that they are all mental or physical objects.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], One.1)
     A reaction: No one, of course, has ever claimed that they are, but this is a good starting point for assessing the ontology of mathematics. We are going to need 'rules', which can deduce the multitudinous mathematical objects from a small ontology.
Maths is pattern recognition and representation, and its truth and proofs are based on these [Resnik]
     Full Idea: I argue that mathematical knowledge has its roots in pattern recognition and representation, and that manipulating representations of patterns provides the connection between the mathematical proof and mathematical truth.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], One.1)
     A reaction: The suggestion that patterns are at the basis of the ontology of mathematics is the most illuminating thought I have encountered in the area. It immediately opens up the possibility of maths being an entirely empirical subject.
Congruence is the strongest relationship of patterns, equivalence comes next, and mutual occurrence is the weakest [Resnik]
     Full Idea: Of the equivalence relationships which occur between patterns, congruence is the strongest, equivalence the next, and mutual occurrence the weakest. None of these is identity, which would require the same position.
     From: Michael D. Resnik (Maths as a Science of Patterns [1997], Three.10.3)
     A reaction: This gives some indication of how an account of mathematics as a science of patterns might be built up. Presumably the recognition of these 'degrees of strength' cannot be straightforward observation, but will need an a priori component?
9. Objects / C. Structure of Objects / 2. Hylomorphism / d. Form as unifier
One thing needs a single thing to unite it; if there were two forms, something must unite them [Aquinas]
     Full Idea: One thing simpliciter is produced out of many actually existing things only if there is something uniting and tying them to each other. If Socrates were animal and rational by different forms, then to be united they would need something to make them one.
     From: Thomas Aquinas (Quaestiones de anima [1269], 11c), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 25.2
     A reaction: This is the reply to the idea that a single thing is just an interesting of many sortal essences. It presumes, of course, that a thing like a horse has something called 'unity'.
10. Modality / B. Possibility / 8. Conditionals / a. Conditionals
Validity can preserve certainty in mathematics, but conditionals about contingents are another matter [Edgington]
     Full Idea: If your interest in logic is confined to applications to mathematics or other a priori matters, it is fine for validity to preserve certainty, ..but if you use conditionals when arguing about contingent matters, then great caution will be required.
     From: Dorothy Edgington (Conditionals [2001], 17.2.1)
10. Modality / B. Possibility / 8. Conditionals / b. Types of conditional
There are many different conditional mental states, and different conditional speech acts [Edgington]
     Full Idea: As well as conditional beliefs, there are conditional desires, hopes, fears etc. As well as conditional statements, there are conditional commands, questions, offers, promises, bets etc.
     From: Dorothy Edgington (Conditionals [2001], 17.3.4)
10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals
Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? [Edgington]
     Full Idea: Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? Are they non-truth-functional, like 'because' or 'before'? Do the values of A and B, in some cases, leave open the value of 'If A,B'?
     From: Dorothy Edgington (Conditionals [2001], 17.1)
     A reaction: I would say they are not truth-functional, because the 'if' asserts some further dependency relation that goes beyond the truth or falsity of A and B. Logical ifs, causal ifs, psychological ifs... The material conditional ⊃ is truth-functional.
'If A,B' must entail ¬(A & ¬B); otherwise we could have A true, B false, and If A,B true, invalidating modus ponens [Edgington]
     Full Idea: If it were possible to have A true, B false, and If A,B true, it would be unsafe to infer B from A and If A,B: modus ponens would thus be invalid. Hence 'If A,B' must entail ¬(A & ¬B).
     From: Dorothy Edgington (Conditionals [2001], 17.1)
     A reaction: This is a firm defence of part of the truth-functional view of conditionals, and seems unassailable. The other parts of the truth table are open to question, though, if A is false, or they are both true.