1070s–1109

Anselm of Canterbury: the Ontological Argument and the Satisfaction Theory

Anselm was born in Aosta. At 26 he entered the Benedictine monastery of Bec in Normandy, where he succeeded Lanfranc first as prior and, in 1093, as Archbishop of Canterbury. Conflicts with English kings over the church's independence and lay investiture sent him into exile more than once.

He is regarded as the founder of scholasticism. While still at Bec he wrote the "Monologion" and "Proslogion" (1077–1078), and later the treatise "Why God Became Man". The latter shaped the Western understanding of atonement for centuries, though critics raised objections to it. Answering the nominalist Roscelin, Anselm defended the reality of the Trinity against charges of tritheism.