The Proslogium, also known as the Discourse on the Existence of God, is an attempt by the medieval cleric Anselm to prove beyond contention the existence of God.

Anselm wrote this discourse, not from the perspective of an attempt to convince non-Christians of the truth of Christianity, but rather from the perspective of a Christian believer seeking a rationale for their faith. His original title for the discourse, in fact, was Faith Seeking Understanding. The Proslogium is the source for Anselm's famous ontological argument for the existence of God--that is, the argument in favor of God's existence by definition. While opinions concerning the ontological argument vary widely (and have from the moment the Proslogium was written), it is generally agreed that the argument is most convincing to Anselm's intended audience: that is, Christian believers seeking a rational basis for their belief in God.

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