The principle of adaptation is quite interesting, and is related to the progress principle. Hedonic adaptation means that very often it is changes in circumstances, not absolute conditions, that affect our happiness. Many people today feel they could not live without their x, where x is a new versatile solution for modern living, a new type of phone, say. But of course, they could. They have simply gotten so used to living with that phone, that they find it hard to imagine life without it. They have adapted to it. The happiness we experience is based on a comparison between our current state, and the one we have adapted to. If you take the phone away suddenly, they will be unhappy, but over time, they will adapt to not having it too.

Lottery winners, perhaps the luckiest people of all, become extremely happy after winning. They are suddenly free of financial problems, their sex appeal immediately increases, and they can do or buy almost anything they want. But over time, they adapt to the high life, and their happiness returns to just about where it was before.

Quadriplegics experience something similar after losing the use of their limbs. Their happiness understandably takes a considerable dip. But over time, they being to adapt to their situation; their goals and expectations change, and their happiness returns to almost (but not quite) the same level it was originally.

In many ways, unfortunately, hedonic adaptation is in direct competition with the way modern life is set up. The deal is simple; you get the money, the clothes, the big house, and the nice car, and then bang! Well done champ, you made it, you’ll be happy forever. But then the new car is released, the new clothing line comes out, and you want a house with a pool and an ocean view. Your expectations rise, what was once a luxury becomes a necessity, and you find yourself wanting more again, like a hamster on a treadmill (this idea is often called the hedonic treadmill, in fact). There’s nothing wrong with wanting a better life for yourself and your family, but much of what you think will bring you that, won’t, because you’ll adapt to it. Meanwhile, if you’re spending a lot of your time working just to chase after these things, you’ll miss out on the opportunity to do other things that will have a stronger impact on your happiness.

Refs:

Brickman, P., Coates, D., & Janoff-Bulman, R. (1978). Lottery Winners and Accident
Victims: Is Happiness Relative. Journal of Personality and Social Psychology, 36(8), 917-
927.