R. C. Moore has an interesting comment that is at risk of being lost in the flood of recent comments, and I don’t want to let it just slip by, so I’m promoting it up here where I can answer it more easily.
RC is making the claim that my Gospel Hypothesis is not valid because it cannot be constructed via propositional logic.
There’s no requirement that hypotheses must be formed by propositional logic. We just need to be able to predict what consequences would result from the situation described.
Sorry, I disagree, A testable hypothesis (which is the hypothesis at hand) must be valid in terms of propositional logic. You stated it yourself,
Not all statements make valid hypotheses, however. “Loki works in mysterious ways” is a statement that really covers just about any possible outcome. We can’t really look at, say, today’s weather report and tell whether it supports or refutes the statement that Loki works in mysterious ways. Likewise, inherently self-contradictory statements are untestable. If we say “Childless unmarried spouses have healthier children,” we’re not going to be able to describe an observable set of consequences against which we could compare the evidence.
The reason these hypotheses are invalid is because they cannot be correctly described using propositional logic.
You gave good examples, you just forgot some other failures, such as tautology and non sequeter.
Tautology and non-sequitur, however, are fallacies that describe incorrect conclusions, not incorrect premises. I think what’s happening here is that RC is getting a little ahead of the game and is trying to draw conclusions before we’re done defining the premises.
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