The hedonic set point is a level of happiness to which humans tend to return to throughout their lives, even after dramatic events like winning the lottery or becoming paraplegic. It is a relevant concept throughout effective altruism: knowledge of hedonic set points (like other aspects of neuroscience) informs efforts to improve the well-being of at least humans and potentially also other mammals or even evolved creatures in general. It is also an argument for wealthy people to give large amounts of money to charity. Beyond a certain point having more money will not make you significantly happier, so it’s natural to give it away to where it can make a big difference.

In chapter 2 of part 2 of his famous classic How to Win Friends and Influence People (also recommended to effective altruists in general), Dale Carnegie writes on the idea that is now associated with hedonic set points:

Everybody in the world is seeking happiness – and there is one sure way to find it. That is by controlling your thoughts. Happiness doesn’t depend on outward conditions. It depends on inner conditions.

It isn’t what you have or who you are or where you are or what you are doing that makes you happy or unhappy. It is what you think about it. For example, two people may be in the same place, doing the same thing; both may have about an equal amount of money and prestige – and yet one may be miserable and the other happy. Why? Because of a different mental attitude. I have seen just as many happy faces among the poor peasants toiling with their primitive tools in the devastating heat of the tropics as I have seen in air-conditioned offices in New York, Chicago or Los Angeles.

“There is nothing either good or bad,” said Shakespeare[‘s Hamlet], “but thinking makes it so.”

Abe Lincoln once remarked that “most folks are about as happy as they make up their minds to be.” He was right. I saw a vivid illustration of that truth as I was walking up the stairs of the Long Island Railroad station in New York. Directly in front of me thirty or forty crippled boys on canes and crutches were struggling up the stairs. One boy had to be carried up. I was astonished at their laughter and gaiety. I spoke about it to one of the men in charge of the boys. “Oh yes,” he said, “when a boy realises that he is going to be a cripple for life, he is shocked at first; but after he gets over the shock, he usually resigns himself to his fate and then becomes as happy as normal boys.”

I felt like taking my hat off to those boys. They taught me a lesson I hope I shall never forget.