"Those who cannot remember the past are condemned to repeat it." -George Santayana*
I've got bad news, George, I think we're condemned to repeat it anyway. Knowing what's bad for you doesn't seem to act as a deterrent, really, it just keeps you from having anyone but yourself to blame. Actually, that's not true either, you can blame someone else even when you know better.
We're a collective Bart Simpson, forever reaching for the cupcake that we know is electrified. But we don't take responsibility. We blame it all on Lisa for conducting her "Is Humanity Dumber than a Hamster?" experiment.
But we showed her! Just like Bart and his "Can Hamsters Fly Planes?" experiment, which won over the crowd even though it had no merit, we made the movie "Avatar"!*
*Coincidentally, this line is often mis-quoted and mis-attributed, meaning that the people who say it don't remember the past very well.