Steven Pinker -- How the Mind Works - Hampshire High Italian ...

158 HOW THE MIND WORKShas clear -lens&oval eyeballseeswellhas clearlens(AA)has clear —lens &oval eyeballseeswellhas clear —lens &round eyeballsees •better•• reproduces• has clearlens &round eyeballThis molecule or crystal was a product not of natural selection but of thelaws of physics and chemistry. (If it were a product of selection, wewould have an infinite regress.) Replicators are wont to multiply, and asingle one multiplying unchecked would fill the universe with its greatgreat-great-.. .-great-grandcopies. But replicators use up materials tomake their copies and energy to power the replication. The world isfinite, so the replicators will compete for its resources. Because no copyingprocess is one hundred percent perfect, errors will crop up, and notall of the daughters will be exact duplicates. Most of the copying errorswill be changes for the worse, causing a less efficient uptake of energyand materials or a slower rate or lower probability of replication. But bydumb luck a few errors will be changes for the better, and the replicatorsbearing them will proliferate over the generations. Their descendantswill accumulate any subsequent errors that are changes for the better,including ones that assemble protective covers and supports, manipulators,catalysts for useful chemical reactions, and other features of whatwe call bodies. The resulting replicator with its apparently well-engineeredbody is what we call an organism.Natural selection is not the only process that changes organisms overtime. But it is the only process that seemingly designs organismsover time. Dawkins stuck out his neck about extraterrestrial evolutionbecause he reviewed every alternative to selection that has been proposedin the history of biology and showed that they are impotent toexplain the signature of life, complex design.The folk theory that organisms respond to an urge to unfold intomore complex and adaptive forms obviously won't do. The urge—and, more important, the power to achieve its ambitions—is a bit ofmagic that is left unexplained.The two principles that have come to be associated with Darwin'spredecessor Jean Baptiste Lamarck—use and disuse, and the inheri-