Say you think the falsehood of the homo economicus model provides some kind of special basis for a new kind of paternalism. Does that mean you think people up to now have been making a hash out of their lives? Maybe you do, which is why you think people continue to smoke or get really, really fat. But, look: lots of people manage to live a long time, save enough money for retirement, and even get along with their kids. How do they ever do it? It seems to me that strict rational choice assumptions are false and, also, most people do a fine job of living their lives. So, yeah: false theories of behavior tend not to do a very good job of accounting for lives well-lived. If you had thought that lives could not be well-lived unless some theory was true, then the persistence of good lives after the death of that theory ought to put the thought to rest, shouldn't it?