Random mutations much more easily debilitate genes than improve them, and that this is true even of the helpful mutations. Let me emphasize, our experience with malaria’s effects on humans (arguably our most highly studied genetic system) shows that most helpful mutations degrade genes. What’s more, as a group the mutations are incoherent, meaning that they are not adding up to some new system. They are just small changes - mostly degradative - in pre-existing, unrelated genes. The take-home lesson is that this is certainly not the kind of process we would expect to build the astonishingly elegant machinery of the cell. If random mutation plus selective pressure substantially trashes the human genome, why should we think that it would be a constructive force in the long term? There is no reason to think so.

We are only chance visitants to this jungle of blind mutations. The natural world existed when we did not, and it will continue to exist long after we are gone. The supernatural crept into life only when the door of consciousness was opened in our heads. The moment we stepped through that door, we walked out on nature. Say what we will about it and deny it till we die--we are blighted by our knowing what is too much to know and too secret to tell one another if we are to stride along our streets, work at our jobs, and sleep in our beds. It is the knowledge of a race of beings that is only passing through this shoddy cosmos.