In order to understand what in the end the Praise of Folly is about, it is necessary to point to the reactionary nature of late medieval scholastic theology. The high middle ages had seen in the work of Thomas Aquinas (c. 1225-74) a daring attempt to build a theological system on certain Aristotelian premises in psychology and the theory of knowledge. He successfully provided the basis for a more optimistic understanding of the world and human experience than that inherited from Augustine, whose later writings had emphasized the effects of original sin on man's natural powers.