Elasticity is a key concept from behavior change research. Scientists call it “psychological flexibility.” A related example that Jeff uses, when it comes to his diet, is the “80/20 rule”: 80 percent of the time he eats healthy food, and the rest of the time he eats whatever he wants. This way, he rarely feels deprived. It’s like a steam-release valve. I liked this concept so much I instituted my own version: the 60/40 rule.
