Pronunciation: (prob'u-bu-liz"um),[key] —n. 1. Philos.the doctrine, introduced by the Skeptics, that certainty is impossible and that probability suffices to govern faith and practice.
2. Rom. Cath. Theol.a theory that in cases of doubt as to the lawfulness of an action, it is permissible to follow a sound opinion favoring its lawfulness. Cf. equiprobabilism.