The Blind Watchmaker

Imagine walking across a heath, dry ground covered in scrub, and stumbling on a watch lying on the ground. Nobody would think it sprang from the earth or was shaped by the wind: the gears fit together too well, the hands turn at just the right speed, everything looks designed to serve a function. That was the argument of the English clergyman William Paley, published in 1802: if a watch needs a watchmaker, a living being, far more complex than any watch, would also need a creator.

The Blind Watchmaker sets out to take apart that comparison without denying its starting point: yes, living things are complex and look designed. The turning point of the whole book is showing that there is an explanation for that appearance of design that doesn't involve any designer.

Dawkins's answer to the watch argument is natural selection: a process that produces complex things fitted to their environment without anyone having designed anything. Each generation is born with small variations, some help animals survive and leave more young, and those are the variations that spread in the next population. Repeated over millions of generations, the accumulated result looks, from a distance, planned.

There is a watchmaker, in the sense that there is a process that assembles life's complexity piece by piece. But it doesn't see the finished watch before it starts, has no plan, and doesn't choose with a future goal in mind: it is blind, and only reacts to what works right now. A real watchmaker knows where he wants to end up before assembling the first piece; natural selection only lets survive what has already worked up to that point.

One of the biggest obstacles to accepting natural selection is imagining how something as complicated as an eye could come from pure chance. Dawkins calls this problem Mount Improbable: a mountain with a sheer vertical cliff on one side, impossible to climb in a single jump, and a gentle slope on the other side, rising gradually to the same summit. Reaching the top in one leap is almost impossible; going up the slope, one step at a time, is a doable hike, even if it takes many generations.

Natural selection never scales the cliff: it always finds the slope, because every intermediate step has to work on its own and give some immediate advantage. It's like moving up at work: nobody jumps from intern to director overnight, but climbing one rung at a time, gaining experience that supports the next step, is a path anyone recognizes.