“The end of nature” can be taken in two ways. If we take the phrase to be talking about, for example, what we would see if we just let nature run its course, as though it was unfolding for us on a video screen, then we see a story of sheer vanity. There may be many other generations after this one, but irrespective of how long the affair goes on, the time is coming when the sun either goes dim, or it can no longer hold down its own weight; and the earth either glows and gets burnt up like a cinder or goes as cold as ash. There won’t remain any tale of man- not even one told by an idiot. Nature does not have the power to save the memory of anything from oblivion: Homer’s Iliad, the memory of the battle of Thermopylae, Chartes Cathedral, Euclid’s Elements, The music of Palestrina… all of these things will vanish into the same faceless oblivion which billions have already vanished into, and which promises to claim each of us on any of the few thousand days that are coming. Taken in this sense, “the end of nature” means an event of total vanity.
I described the account just given as one “unfolding on a video screen”. It is nature as it presents itself to us according to mere sensation- wordless and just seen. Looking at nature with the aid of mind tells a different story, and the truer story. Mere sensation is as different from sensation and mind as seeing a persons face is from knowing their character; or as different as saying a word and knowing its definition. As Aquinas points out, intelligence is capable of “reading the interiors (inter/ legere)” and according to mind seeing the interior of what is sensed, we can tell that nature is being moved, being caused, being held in its contingent existence, being caused by some supereminent agent and end, and being ordered and determined by mind. When nature is taken according to sense and mind, “the end of nature” means an end which is outside of nature, and to which nature is both tending and testifying. Taken in this sense “the end of nature” reveals an extrinsic and unifying purpose of nature, which makes it blasphemous to claim that nature is totally without purpose.