Behave: The Biology of Humans at Our Best and Worst

by Robert M. Sapolsky

“The opposite of love is not hate; its opposite is indifference.” The biologies of strong love and strong hate are similar in many ways, as we’ll see. Which reminds us that we don’t hate aggression; we hate the wrong kind of aggression but love it in the right context.

The hypothalamus, a limbic structure, is the interface between layers 1 and 2, between core regulatory and emotional parts of the brain.

While the hypothalamus dwells at the interface of layers 1 and 2, it is the incredibly interesting frontal cortex that is the interface between layers 2 and 3.