To mention a colorful example, the nineteenth-century German scientist Karl Vogt once wrote that “thoughts stand in the same relation to the brain as… - Gary F. Marcus

Cell differentiation can turn neurons into everything from clocks that control circadian rhythms to photoreceptors that convert light into electrical-chemical impulses or decision makers that tally votes and decide courses of action. In the retina (often used as a case study because it can be directly and naturally stimulated), there are at least fifty different kinds of neurons specialized to different tasks, such as looking for motion, recognizing colors, detecting objects in low light, and measuring brightness and contrast. In the brain as a whole, there may be as many as 10,000 different kinds of neurons, each contributing to a different aspect of mental life.

Language builds on our cognitive capacities to reason about the goals and intentions of other people, on our desire to imitate, our desire to communicate, and our twin capacities for using convention to name things and sequence to indicate differences between differing possibilities.

"We should be far more worried about "genetic enhancement"- efforts to artificially construct "improved humans." Here I side with Fukuyama: Although the technology for improvement is close at hand, it comes with great risks, and some of the greatest risks stem from the complexity of the underlying biology. As we have seen, the basic logic by which genes operate-the regulatory IF conjoined with protein template THEN- is straightforward- which is why genetic enhancement might be possible, in principle. But the combined effects of 30,000 genes far exceed our comprehension; if we know the general principles, we don't know the details, and what we don't know really could hurt us."