As I shared with my professors years ago when I was in college, if all the evidence in the universe turns against creationism, I would be the first to admit it, but I would still be a creationistbecause that is what the Word of God seems to indicate. — Kurt Patrick Wise
Is it legitimate, however, if someone says, "If x, then y," to then assume, "If not x, then not y?" — MichaelJYoo
Is it ever reasonable to concede the truth of each of the premises of a deductive argument and yet deny the conclusion — MichaelJYoo
suppose, for the sake of my question, that premise 1 and 2 each have a 65% chance of being true — MichaelJYoo
I don't know if "this" is the case, but rational thinkers can provisionally, or temporarily, accept stated premises, without committing to a conclusion drawn from them. Unfortunately, most people are poor judges of statistical probability. That's the whole point of Bayesian Inference or "subjective probability".Since this is the case, can it be rational to think premises of a deductive argument are true and yet waver on the conclusion being true? — MichaelJYoo
while each premise individually considered is more likely to be true than their contraries, the chance (mathematically speaking, in this example) that both are true at the same time is 0.65 * 0.65, or 0.4225 (42.25%) — MichaelJYoo
If F(65%) then G(65%)
F(65%)
Therefore, G(65%) — Moliere
We had a probability for the whole conditional, plus a second premise giving a probability for its antecedent, but no probability for the consequent. If we already knew that pr(G) = 0.65, why we would we bother trying to calculate it? — Srap Tasmaner
suppose a friend were to say to us: "If you attend my party, you will receive a prize." Immediately, we would think, "If I don't attend the party, I won't receive a prize. But since I want a prize, I must attend the party." — MichaelJYoo
Works out better for the OP's point, that the conclusion is less likely than each initial premise — Moliere
Logic can be mapped onto probability somewhat naturally...Formally, though, it does make some sense to think of logic as a special case of a more general calculus of probabilities. — Srap Tasmaner
Not sure what vocabulary we should use for this sort of thing, but “validity” feels really out of place. Once you’re doing probabilities, that’s what you’re doing. — Srap Tasmaner
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