HYPOTHESIS, (formed of υπο "under," and θεσις positio, of θεσμαι pono, "I put"), is a proposition or principle which we suppose, or take for granted, in order to draw conclusions for the proof of a point in question.
In disputation, they frequently make false hypotheses, in order to draw their antagonists into absurdities; and even in geometry truths are often deducible from such false hypotheses.
Every conditional or hypothetical proposition may be distinguished into hypothesis and thesis: the first rehearses the conditions under which any thing is affirmed or denied; and the latter is the thing itself affirmed or denied. Thus, in the proposition, a triangle is half of a parallelogram, if the bases and altitudes of the two be equal; the latter part is the hypothesis, "if the bases," &c. and the former a thesis, "a triangle is half a parallelogram."
In strict logic, we are never to pass from the hypothesis
Hypothesis theist to the theist; that is, the principle supposed must be proved to be true, before we require the consequence to be allowed.