New Delhi, April 25 -- Oliver Sweet opens his book, The Rules That Make Us: How Culture Shapes the Way We Act, Think, Buy and Believe, with a joke. Culture and Cognition walk into a bar. Cognition studies the menu carefully, weighing options, considering moods, wondering about the barman's skill. It leans over to Culture: "I've made a choice." Culture looks up. "I'll have what they're having."

It is a terrific opening: crisp, clean, and carrying more weight than its lightness suggests. Because that, in essence, is Sweet's central argument: that culture is the invisible architecture of our choices, the water which the fish live in but cannot see. We do not decide so much as inherit our decisions. We imagine ourselves as individuals exerci...