My father in his last years was tentatively diagnosed as having Alzheimer’s. I never believed it. Now, new research on the human genome and, among other things, how canaries learn new songs brings us a little closer to understanding how memory works, and why it doesn’t.

How is it that so many young men and women born and raised in secular, post-Christian, democratic societies in Western Europe (or the U.S.) acquire the passion to kill and die for Islam?