“Faith and reason are like two wings on which the human spirit rises to the contemplation of truth.” Those opening words of Pope Saint John Paul II's encyclical Fides et ratio have come to encapsulate the Catholic teaching that one need not — indeed, cannot — choose between supernatural faith and natural reason. Far from being inimical to each other, the late pontiff argues, faith and reason are mutually reinforcing and complementary modes of grasping truth; they stand or fall together.