Time, we believe, moves linearly. From one event to another, cause leads to effect. But memory is anything but linear. Rather, it builds on itself in a great spiraling web, each idea leading to three others, which branch into an interconnected labyrinth of recollection.

I tell you this so that you will understand. Understand what is to come, understand what has happened, and understand what I mean when I say: I was lost in my own mind.

Mercifully, we can start at the ...