Ideas from 'Conditionals' by Frank Jackson [2006], by Theme Structure

[found in 'Blackwell Guide to Philosophy of Language' (ed/tr Devitt,M/Hanley,R) [Blackwell 2006,0-631-23142-0]].

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5. Theory of Logic / E. Structures of Logic / 2. Logical Connectives / a. Logical connectives

14352

'¬', '&', and 'v' are truth functions: the truth of the compound is fixed by the truth of the components

10. Modality / B. Possibility / 8. Conditionals / b. Types of conditional

14360

Possible worlds for subjunctives (and dispositions), and no-truth for indicatives?

10. Modality / B. Possibility / 8. Conditionals / c. Truth-function conditionals

14353

Modus ponens requires that A→B is F when A is T and B is F

14354

When A and B have the same truth value, A→B is true, because A→A is a logical truth

14355

(A&B)→A is a logical truth, even if antecedent false and consequent true, so it is T if A is F and B is T

10. Modality / B. Possibility / 8. Conditionals / d. Non-truthfunction conditionals

14358

In the possible worlds account of conditionals, modus ponens and modus tollens are validated

14359

Only assertions have truth-values, and conditionals are not proper assertions

14357

Possible worlds account, unlike A⊃B, says nothing about when A is false

10. Modality / B. Possibility / 8. Conditionals / f. Pragmatics of conditionals

14356

We can't insist that A is relevant to B, as conditionals can express lack of relevance