A man has as many social selves as there are distinct groups of persons about whose opinion he cares. He generally shows a different side of himself to each of these different groups. —WILLIAM JAMES Meet Professor Brian Little, former Harvard University psychology lecturer and winner of the 3M Teaching Fellowship, sometimes referred to as the Nobel Prize of university teaching. Short, sturdy, bespectacled, and endearing, Professor Little has a booming baritone, a habit of breaking into song and twirling about onstage, and an old-school actor’s way of emphasizing consonants and elongating vowels. He’s been described as a cross between Robin Williams and Albert Einstein, and when he makes a joke that pleases his audience, which happens a lot, he looks even more delighted than they do. His classes at Harvard were always oversubscribed and often ended with standing ovations. In contrast, the man I’m about to describe seems a very different breed: he lives with his wife in a tucked-away house on more than two acres of remote Canadian woods, visited occasionally by his children and grandchildren, but otherwise keeping to himself.