Want Fewer Fries With That?

By PAUL ROZIN and ANDREW B. GEIER

On a flight from Philadelphia to Chicago that one of us took some time ago, a full lunch was served at 4 p.m. Six of the nine passengers in sight ate all of it. Simply put, it was there. And in a study conducted with people who have amnesia, and who therefore cannot remember that they have just eaten, the subjects consumed second and even third...