It’s helpful, as with his Third Way, to begin with a metaphor, in order to get an intuitive feel for the proof.
St. Thomas laid the intellectual groundwork for modern natural science — the absolute distinction between existence and essence.
The design we infer in nature is an insight we abstract from our senses, but the inference itself is acquired by our reason.
“There has to be something in addition to just the DNA sequences alone that explains development.”
“Follow the evidence wherever it leads.” It’s almost the official rallying cry of intelligent design proponents.