The exchange with my “pro-evolution” correspondent has been continuing. I thought I’d share part of my latest reply:

With regard to Aristotle, it’s not a question of the origin of species, which is clearly to be found in the Creator, but in the hierarchy of life. Aristotle presents an ascending hierarchy from the lowest forms of life to the highest, i.e. man. His hierarchy mirrors the hierarchy employed by Darwinians, though of course he was writing 2,300 years or so before Darwin. The difference is that Aristotle places man above all the other creatures because of his ability to imagine and to reason in an abstract sense. The point is that the hierarchy has nothing to do with evolution. The fact that modern science has discovered that the animals closest to humanity in the hierarchy are more closely related genetically to man than those further down the hierarchy is exactly what we would expect, both as Christians and/or as classical philosophers. The fact that we share most of the same building materials as the apes is true; it is the material that God has used to create us. We also share most of the same materials as plants, in the sense that we are built of hydrocarbons; and nearly everything in creation, including inanimate objects, such as rocks, are built of the same basic molecular material. We have a lot in common with everything else in creation at the molecular or sub-molecular level. If apes are close cousins in terms of their chemistry, we should not forget that even a stone is a more distant cousin! We all bear the fingerprints of the One who created us. Logically, this points to the fact that we are related to a single source, not that we evolved from rocks to plants to animals to man by an impenetrably improbable, i.e. patently impossible, accident—or, to be accurate, billions upon billions of such patently impossible accidents. It seems to me that a belief in this sort of evolution involves a far greater degree of credulity than anything in the Creed.