Determined: A Science of Life without Free Will

by Robert M. Sapolsky

Take one lone heroic rat that, for some reason, can save the world from disaster by developing a conditioned eyeblink response. And he screws up, doesn’t do it, lets the world down. Afterward, everyone is pissed at the rat, blaming him for not conditioning. To which he can say, “It’s not my fault—I didn’t get conditioned because, one second before, my interpositus nucleus wasn’t as responsive to the conditioned stimulus; because a few hours before, my stress hormone levels were elevated, which guaranteed that the interpositus would be particularly resistant to conditioning; because back in my childhood, my mother was taken from me, and this changed gene regulation in the interpositus, permanently increasing levels of a hormone receptor there; because back millions of years ago, my species evolved to be highly dependent on maternal care after birth, and the genes needed to make lifelong changes in circuitry if the mother is absent.”