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13764
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Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? [Edgington]
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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'?
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From:
Dorothy Edgington (Conditionals [2001], 17.1)
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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.
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13765
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'If A,B' must entail ¬(A & ¬B); otherwise we could have A true, B false, and If A,B true, invalidating modus ponens [Edgington]
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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).
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From:
Dorothy Edgington (Conditionals [2001], 17.1)
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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.
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3238
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'Dead person' isn't a contradiction, so 'person' is somewhat vague [Williams,B]
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Full Idea:
If we say (in opposition to a physical view of identity) that when Jones dies 'Jones ceases to exist' but 'Jones' body does not cease to exist', this shouldn't be pressed too hard, because it would make 'dead person' a contradiction.
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From:
Bernard Williams (Are Persons Bodies? [1970], p.74)
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A reaction:
A good point, which nicely challenges the distinction between a 'human' and a 'person', but the problem case is much more the one where Jones gets advanced Alzheimer's, rather than dies. A dead body ceases as a mechanism, as well as as a personality.
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3239
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You can only really love a person as a token, not as a type [Williams,B]
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Full Idea:
If you love a person as a type instead of as a token (i.e. a "person", instead of a physical body) you might prefer a run-down copy of them to no person at all, but at this point our idea of loving a person begins to crack.
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From:
Bernard Williams (Are Persons Bodies? [1970], p.81)
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A reaction:
Very persuasive. If you love a person you can cope with them getting old. If you own an original watercolour, you can accept that it fades, but you would replace a reproduction of it if that faded. But what, then, is it that you love?
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