in Logic and Rhetoric, an argument consisting only of two propositions, an antecedent, and a consequent deduced from it. The word is Greek, ἐνθυμημα, formed of the verb ἐνθυμεῖσθαι, to think, conceive, a compound of εν, and θυμος, mind.

The enthymeme is the most simple and elegant of all argumentations, being that which a man, in arguing closely, commonly makes, without attending at all to the form. Thus, the verse remaining of Ovid's tragedy entitled Medea contains an enthymeme: "Sereare potui, perdere ac possim regnum.—'I was able to save you; consequently to have destroyed you.' The beauty would have been lost had all the propositions been expressed; the mind is displeased with a rehearsal of what is nowise necessary.

Sometimes also the two propositions of an enthymeme are both included in a single proposition, which Aristotle calls an enthymemal sentence, of which he gives this instance: Mortal, do not bear an immortal hatred. The whole enthymeme would be, Thou art mortal, let not, therefore, thy hatred be immortal.