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[TUTORIAL F05] Inappropriate presumption

Fallacies of inappropriate presumption are cases where we have explicitly or implicitlymade an assumption that is not reasonable to accept in the relevant context. Someexamples:

Many people like to ask whether human nature is good or evil. This presupposes thatthere is such a thing as human nature and that it must be either good or bad. But whyshould these assumptions be accepted and are they the only options available? Whatif human nature is neither good nor bad? Or what if good or bad nature applies only toindividual human beings?Consider the question "Have you stopped being an idiot?" Whether you answer "yes"or "no", you admit that you are, or have been, an idiot. Presumably you do not want tomake any such admission. We can point out that this question has a false assumption."Same-sex marriage should not be allowed because by definition a marriage shouldbe between a man and a woman." This argument assumes that only a heterosexualconception of marriage is correct. But this begs the question against those whodefend same-sex marriages and is not an appropriate assumption to make whendebating this issue.