Scientists debate whether we lose the ability to resist temptation over time, or just no longer want to.
As far as examples of willpower go, one of the most impressive you'll ever find is the "incredible Buddha boy"chronicled in GQ a few years back by George Saunders. The boy had been meditating under a tree for seven months, evidently without food or water. It was a display of self-control so haunting that readers couldn't help but wonder how such a person could exist while the rest of us find it so hard--really, impossible--to rise from the couch and go to the gym, or read a book, or in some cases just reach the remote.