Where does consciousness come from?

Consciousness is a weird thing. Being aware of your own feelings, being able to plan out and think through your actions and the consequences of those actions...and being able to analyze other people and how they would react, is a trait assimilated uniquely with humans. But where does it come from? Richard Dawkins' groundbreaking book on biology, The Selfish Gene, has an interesting take on it.

One of the most interesting methods of predicting the future is simulation. /…/ If simulation is such a good idea, we might expect that survival machines would have discovered it first (he is referring to the use of computer simulation). After all, they invented many of the other techniques of human engineering long before we came to the scene: the focusing lens and the parabolic reflector, frequency analysis of sound waves, servo-control, sonar, buffer storage of incoming information, and countless others with long names, whose details don’t matter. What about simulation? Well, when you yourself have a difficult decision to make involving unknown quantities in the future, you do go in for a form of simulation. You imagine what would happen if you did each of the alternatives open to you. You set up a model in your head, not of everything in the world, but of the restricted set of entities which you think may be relevant. You may see them vividly in your mind’s eye, or you may see and manipulate stylized abstractions of them. /…/ Survival machines that can simulate the future are one jump ahead of survival machines who can only learn on the basis of overt trial and error. The trouble with over trial is that it takes time and energy. The trouble with overt error is that it is often fatal. Simulation is both faster and safer.

The evolution of the capacity to simulate seems to have culminated in subjective consciousness. Why this should have happened is, to me, the most profound mystery facing modern biology. There is no reason to suppose that electronic computers are conscious when they simulate, although we have to admit that in the future they may become so. Perhaps consciousness arises when the brain’s simulation of the world becomes so complete that it must include a model of itself.
- quoted from pages 57-9 of the million copy special edition, emphasis mine

The book is filled with mind-bogglingly simple* but elegant explanations of the world around us. It's a popular science book on biology and more specifically evolution, but there's a lot for everyone to learn from it. I'm not a biology person, but this book definitely has a special place on my popular science bookshelf along with Carl Sagan's Cosmos.

* Simple doesn't mean the conclusion itself was easy to come to. Simple is rather a reference to Occam's Razor.