n. 想像, 推测, 推想

[法] 假定, 推定, 推测

Supposition \Sup`po*si"tion\, n. [F. supposition, L. suppositio
a placing under, a substitution, fr. supponere, suppositium,
to put under, to substitute. The word has the meaning
corresponding to suppose. See {Sub-}, and {Position}.]
1. The act of supposing, laying down, imagining, or
considering as true or existing, what is known not to be
true, or what is not proved.

2. That which is supposed; hypothesis; conjecture; surmise;
opinion or belief without sufficient evidence.

This is only an infallibility upon supposition that
if a thing be true, it is imposible to be false.
--Tillotson.

He means are in supposition. --Shak.