The cereal aisle in any big supermarket has got to be one of the most amazing expressions of ingenuity in American culture. For centuries the only way to eat grains was as a big, sloppy bowl of gluey glop (gruel, oatmeal, bulgur, cream-of-wheat, porridge). Then a little over a hundred years ago some nineteenth century health food nuts got the idea to toast up those grainy tidbits. Thus the cold cereal phenomenon was born.

Now we look down a football-field-length supermarket aisle at floor to ceiling cereals that offer crunch, sugar, extra-fiber, nuts, fruits, marshmallows, peanut butter, every color of the rainbow, and every size, shape, and texture imaginable. I doubt if Mr. Kellogg could have ever dreamed that so many different products could be created out of his little flakes. When it…