This phrase is from the below paragraph in the book Behave: The Biology of Humans at Our Best and Worst by Robert M. Sapolsky.
The book has a number of personal roots. One is that, having had blessedly little personal exposure to violence in my life, the entire phenomenon scares the crap out of me. I think like an academic egghead, believing that if I write enough paragraphs about a scary subject, give enough lectures about it, it will give up and go away quietly. And if everyone took enough classes about the biology of violence and studied hard, we’d all be able to take a nap between the snoozing lion and lamb. Such is the delusional sense of efficacy of a professor.