No, Thomas Aquinas was not a Darwinist, not even close

Hi Denyse, Thanks very much for posting this excellent article by Logan Paul Gage. There has already been some discussion of Gage's paper on Professor Ed Feser's Weblog. Some readers queried Gage's assertion that Darwinism is incompatible with a belief in essences - despite the fact that Chesterton was of the same opinion, and Darwin evidently affirmed this himself. The discussion got quite technical, but one contributor (Ben Yachov) kindly transcribed a long passage from Professor David Oderberg's book, Real Essentialism on the compatibility of essentialism with evolution. The gist of Professor Oderberg's remarks was that while the accidental properties of a creature belonging to type A might grade imperceptibly into the non-essential accidental features of its descendant, which belongs to a different type, B, nevertheless from a Thomistic perspective there must have been a point in time when a type A creature gave birth to a type B creature - even though a biologist who examined them both would not notice any striking physical difference between parent and offspring. Thus evolution (but not necessarily Darwinism) is compatible with essentialism, appearances notwithstanding. Professor Oderberg's argument is certainly a very ingenious one. Two comments: first, I don't think this argument would please Darwinists at all. They'd probably foam at the mouth in indignation at the thought that someone might attempt to marry gradual evolutionary change with essentialism - especially when Darwin's express aim was to undercut the latter. Second, Professor Oderberg's argument seems to overlook the fact that essences have essential as well as non-essential accidental properties, and that the essential properties of biological organisms (such as animals and plants) are empirical properties too. If the essence of a whale is distinct from that of its land-dwelling ancestor, then there must be some physical characteristics which are proper to whales - and since they are physical, a biologist should be able to detect them too. Thus we should be able to find discontinuities in the fossil record, if essentialism is true. I have argued (in Part 2 of my five-part critique of Professor Michael Tkacz's essay, Thomas Aquinas vs. The Intelligent Designers ) that unique cell types which are distinctive to each family of organisms, as Professor Michael Behe noted in "The Edge of Evolution," probably constitute the empirical criterion which enables us to identify essences. Here's an extract from what I wrote:

...[E]ven if we could scientifically demonstrate that the whale and the hippopotamus shared a common ancestor, this would not establish that the two lineages diverged as a result of purely natural changes - for a whole suite of anatomical changes must have been required to transform a land animal into a creature so exquisitely adapted to life in the water as the whale, and it is doubtful whether Nature could have accomplished these through a Darwinian process, in which variation is random and there is no foresight of long-term goals. Additionally, the existence of transitional forms between land animals and modern whales (such as Rodhocetus) poses no problem for essentialism. What we need to ascertain is whether these forms can be said to constitute distinct and well-defined "natural kinds," in their own right, or whether one transitional form gradually merges into another. Given that whales (order Cetacea) would certainly possess some unique cell types in their bodies, which no other creatures possess, I for one would put my money on the proposition that the transition from land animal to whale was a jerky, discontinuous one, accomplished by means of a few Divinely guided saltations over some major evolutionary hurdles. And if somebody were to ask me, "Well, why didn't God perform the transformation from a land animal to a whale instantaneously, instead of taking ten million years?" I would answer that the question contains a number of unwarranted assumptions. It assumes that a modern whale would have been able to out-compete Rodhocetus, if it were alive back then, which is doubtful, as Rodhocetus was amphibious: it lived on the land as well as in the sea. It assumes that there were no environmental conditions 47 million years ago, that would have been unfavorable to modern whales, despite the fact that the diagram above shows a very marked climate change 35 million years ago, from a "greenhouse Earth" to an "icehouse Earth." The question also assumes that there would have been suitable food for modern whales in the oceans, back in those times. Furthermore, it assumes that the sudden appearance of whales 47 million years ago would not have caused any major ecological disruptions - which is quite an assumption to make, when many scientists now believe (rightly or wrongly) that an increase in atmospheric carbon dioxide levels from 0.04% to 0.08% will eventually result in the extinction of a quarter of the world's species. And finally, the question assumes that an ancestral land animal could have given birth to a modern whale produced by Divine genetic engineering, without dying in the process :)

There are other tensions between Thomism and Darwinism, as I point out in Part 2 of my reply to Professor Michael Tkacz: according to Aquinas, not only do living things belong to definite types or "species," but all creatures, and their bodily organs, are perfectly made, in relation to their proper ends. God makes nothing in vain; thus there are no redundant organs or body parts in living things. And finally, for each and every kind of organism in the natural world, each and every one of its characteristic features was personally designed by God. I don't know of any evolutionary biologist, Christian or otherwise, who would accept these claims. I addressed the question of ID and interventionism in Part 4 of my critique of Professor Tkacz. See especially here: http://www.angelfire.com/linux/vjtorley/thomas4.html#flaw4 . Personally I'm a little bit more "pro-intervention" than Gage, but I wholeheartedly agree with his statement that in the end, the question has to be decided empirically. Thanks once again for posting Logan Paul Gage's brilliantly argued essay, Denyse. vjtorley

Right on, Denyse. What the pettifoggers fail to mention is that, for Thomas, God's love is the final cause and great mover of everything found in nature. According to the medieval worldview, inspired by Thomas and his mixture of Christianity with his "Philospoher," all of nature is a living expression of God's love. This is why the medieval ethos was so appealing to modern intellectuals like Lewis and Tolkien. It is not only incompatible with Darwinism; it is the exact opposite. allanius