Propositions (consisting of a subject and predicate united by the copula) may take a categorical, conditional, or interrogative form. (1) An interrogative, when they ask a Question, (e. g. Does Free-trade benefit the poorer classes?) and imply the possibility of an affirmative or negative resolution of it. (2) A conditional, when they express a Conclusion (e. g. Free-trade therefore benefits the poorer classes), and both imply, and imply their dependence on, other propositions. (3) A categorical, when they simply make an Assertion (e.

g. Free-trade does benefit), and imply the absence of any condition or reservation of any kind, looking neither before nor behind, as resting in themselves and being intrinsically complete.