Crawford concludes that Homo sapiens could not have evolved on the savannas but instead were holed up at the beach, gathering along the shoreline. - Michael S. Gazzaniga

Robert Sapolsky, professor of neurology at Stanford, makes the extremely strong statement: “It’s boggling that the legal system’s gold standard for an insanity defense — M’Naghten — is based on 166-year-old science. Our growing knowledge about the brain makes notions of volition, culpability, and, ultimately, the very premise of a criminal justice system, deeply suspect.

Festinger was the intellectually intense discoverer of “cognitive dissonance,” the idea that when a personal belief is challenged by new information, we tend to ignore the new information in order to reduce mental conflict.

While there are more neural connections within a half brain than between the two halves, there are still massive connections across the hemispheres. Even so, cutting those connections does little to one’s sense of conscious experience. That is to say, the left hemisphere keeps on talking and thinking as if nothing had happened even though it no longer has access to half of the human cortex. More important, disconnecting the two half brains instantly creates a second, also independent conscious system. The right brain now purrs along carefree from the left, with its own capacities, desires, goals, insights, and feelings. One network, split into two, becomes two conscious systems. How could one possibly think that consciousness arises from a particular specific network? We need a new idea to cope with this fact.