The Proslogion (Latin: Proslogium, lit. 'Discourse') is a prayer (or meditation) written by the medieval cleric Saint Anselm of Canterbury between 1077 and 1078. In each chapter, Anselm juxtaposes contrasting attributes of God to resolve apparent contradictions in Christian theology. This meditation is considered the first-known philosophical formulation that sets out an ontological argument for the existence of God.

The original title for this discourse was to be Faith Seeking Understanding.

The Proslogion marked what would be the beginning of Saint Anselm's famous and highly controversial ontological arguments for the existence of God. Anselm's first and most famous argument is found at the end of Chapter II, and it is followed by his second argument. Opinions concerning Anselm's twin ontological arguments widely differ, and have differed since the Proslogion was first conceived.

There are various reconstructions of Anselm's first argument. Scott H. Moore's analysis is as follows:

Donald Viney renders Anselm's second argument as follows:

Source:

Anselm writes in Chapter XI that "you [God] are not only that than which a greater cannot be conceived, but you are a being greater than can be conceived."

There are different translations of the Proslogion.