We are what we repeatedly do. – Aristotle
UPDATE 09.29.09: Apparently, 21 days is a myth. It’s actually more like 30, and some say as long as 66 days (Leo at Zen Habits suggests 30- great post on it here). Regardless, pretty exiting that you can get your neurons to create new pathways in as little as two months.
Perhaps the reason you can’t teach a old dog new tricks is that very few people are interested in small, incremental concerted efforts to change. That’d be my theory. Fo sho.