What is "trilemma"

Trilemma \Tri*lem"ma\, n. [NL., fr. Gr. ? (see Tri-) + ? any thing received, in logic, an assumption. Cf. Dilemma.]

1. (Logic) A syllogism with three conditional propositions, the major premises of which are disjunctively affirmed in the minor. See Dilemma.

2. A state of things in which it is difficult to determine which one of three courses to pursue.

1670s, from dilemma + tri-.

n. 1 A circumstance in which a choice must be made between three options that seem equally undesirable. 2 (context logic English) An argument containing three alternatives, jointly exhaustive either under any condition(s) or under all condition(s) consistent with the universe of discourse of that argument, that each imply the same conclusion.

A trilemma is a difficult choice from three options, each of which is (or appears) unacceptable or unfavourable.

There are two logically equivalent ways in which to express a trilemma: it can be expressed as a choice among three unfavourable options, one of which must be chosen, or as a choice among three favourable options, only two of which are possible at the same time.

The term derives from the much older term dilemma, a choice between two or more difficult or unfavourable alternatives.

The earliest recorded use of the term was by the British preacher Philip Henry in 1672, and later, apparently independently, by the preacher Isaac Watts in 1725.