8 ideas
| 12220 | Is it the sentence-token or the sentence-type that has a logical form? [Fine,K] |
| Full Idea: Do we attribute a logical form to a sentence token because it is a token of a type with that form, or do we attribute a logical form to a sentence type because it is a type of a token with that form? | |
| From: Kit Fine (Quine on Quantifying In [1990], p.110) | |
| A reaction: Since I believe in propositions (as the unambiguous thought that lies behind a sentence), I take it that logical form concerns propositions, though strict logicians don't like this, for fear that logic spills into psychology. |
| 12222 | Substitutional quantification is referential quantification over expressions [Fine,K] |
| Full Idea: Substitutional quantification may be regarded as referential quantification over expressions. | |
| From: Kit Fine (Quine on Quantifying In [1990], p.124) | |
| A reaction: This is an illuminating gloss. Does such quantification involve some ontological commitment to expressions? I feel an infinite regress looming. |
| 13768 | 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) |
| 13770 | 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) |
| 13764 | 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. |
| 13765 | '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. |
| 2596 | Maybe mind and body are parallel, like two good clocks [Leibniz] |
| Full Idea: Two clocks in perfect agreement must be by natural influence, or the control of a craftsman, or their perfect construction at the beginning. Only the third way (of "preestablished harmony" by God) is possible. | |
| From: Gottfried Leibniz (The Nature and Communication of Substance [1690], p.121) | |
| A reaction: Presumably 'natural influence' would cover the possibility that (unnoticed by you, apparently) one clock is attached to the other clock at the relevant points. If they are unconnected, presumably they are quite unaware of one another's existence. |
| 2595 | If the universe is a perfect agreement of uncommunicating substances, there must be a common source [Leibniz] |
| Full Idea: The perfect agreement of so many substances which have no communication whatever with each other can only come from a common source. | |
| From: Gottfried Leibniz (The Nature and Communication of Substance [1690], p.120) |