[tl;dr: Shit happens. Also you can do shit. But you probably can’t change how much you want to do shit.]
[draft as of 2014-09-24]
Hedonic treadmill theory tries to explain how human happiness levels respond to life events. More specifically, it tries to explain why human happiness levels don’t respond much at all to life events, when you measure people’s happiness over the long run. The metaphor of the treadmill is that, no matter how slow or fast you’re running in pursuit of happiness, you’re not actually going anywhere. The failure of consumerism to make people happier, and the need to keep purchasing new products and experiences to maintain the happiness “high”, is often adduced as the most common experience of the hedonic treadmill.
A mental image that is less abusive to our hopes and dreams is the hedonic set-point. The idea here is that a certain point, an amount of happiness, is set biologically and is a stable equilibrium. Life events will knock you around and you can move on your own effort, but like a skateboarder in a half-pipe you’ll eventually end up, one way or another, back in the middle of your range. Remarkably, the effect largely holds true even for such extremes of life as winning the lottery or breaking your neck: several years after the big life change, lottery winners and paraplegics are no happier or unhappier than they were before. It’s not totally settled science, but the effect is robust so it needs some explanation.
In the meantime, I got hungry and sad. Curing the hunger was remarkably easy. Curing the sadness was next on my list, I swear, but I got distracted by an alternate hypothesis. Perhaps there is no set-point encoded in your biology for the amount of happiness you’ll experience, but rather, there could be a set-point encoded in your biology for the amount of happiness you feel compelled to get. Happiness, in such a case, would be functionally analogous to a nutrient.
- After a windfall, people would get more of their happiness nutrient from their environment with no special effort, so their marginal happiness-producing habits would be more weakly motivated, and the habits would gradually be dropped. For example, they might first neglect their less immediately-rewarding social obligations. The speed of return to their baseline level of happiness would depend on how firmly ingrained those habits were.
- After a loss, people would get less of their happiness nutrient from their environment without special effort, so they would feel driven to try new things and adopt as habits the happiness-producing habits with the best marginal return. For example, they might form stronger bonds with family and friends. The speed of return to their baseline level of happiness would probably be slower than for the people who experienced a windfall since it’s typically harder to make a new habit stick than let an old habit go.
As a just-so story, this fits the data I already knew reasonably well. What matters more is whether it makes new predictions, or what amounts to the same thing from my perspective, whether it predicts the results of science that’s already been done but that I didn’t know about. To meaningfully test this, I’m going to need some additional alternate hypotheses.
The “happiness nutrient” hypothesis essentially says that the hedonic set-point is a consequence of behavioral adaptation. The original hedonic set-point hypothesis, if I have understood correctly, was more a matter of cognitive adaptation, which would predict that a return to baseline would occur even if behaviors and external experiences remained unchanged. The final complementary hypothesis is environmental adaptation, which is not the crazy mystical principle of anti-karma promising to punish you with bad for all the good you do and vice versa, but instead a combination of three ordinary effects: first, the regression to the mean of the sorts of events in your daily life; second, human responsiveness such as people being nice to you after you break your neck or conniving to steal your lottery winnings; and third, your short attention span. [tl;dr: You’re un/happy about what is currently going worse/better than expected.] Those three hypotheses carve up the idea space into mutually exclusive and exhaustive categories: it’s in your brain, the rest of your body, or the rest of the world. So for overcompleteness’ sake, my fourth hypothesis is a broad null, and says that the way the other three were carved up was wrong, or that the truth is a fairly even mixture of some of them, or that all of them are a poor fit to reality.
OK, finally we go onward to the predictions! Or rather, belatedly we go back for the retrodictions!
[B: behavior adaptation. C: cognitive adaptation. E: environmental adaptation.]
- Brickman (1978) found that lottery winners and paraplegics have happiness set-points. That supports B and C, but is not clear evidence one way or the other regarding E.
- Silver (1982) found that spinal cord injury victims have happiness set-points. That could support any of B, C, or E.
- Diener & Fujita (2005) found that higher happiness set-points are more stable. That supports B slightly more than C or E.
- Lucas, Clark, Georgellis, & Diener (2006) found that women have happiness set-points for changes in marital status, layoffs, and births of children, but that men do not return to happiness baseline after marriage or layoff. That does not obviously support any of B, C, or E, though if is the case that men are treated as higher status when they are married and employed than when they are unmarried and unemployed, then it would support E, or alternatively, if marriage and employment coerce men into stably better habits than bachelorhood and unemployment, then it would support B. LCGD also found that the amount of adaptation that occurs depends on the individual, which is a fit for B and C, but makes little sense under E.
- Wildeman, Turney, Schnittker (2014) found that prisoners are unhappy and do not return to happiness baseline until they are released. That supports B and E, but not C.
- They didn’t show up on my Googling, but I’ve been told and I believe that there are studies which show that a large factor in a person’s happiness is genetically determined. This would support B and C against E.
Taken together, these look to weakly endorse B. It’s also important to note that there are some interventions known to produce lasting happiness improvements.
- Fix mental health problems.
- Get counseling.
- Learn to be extroverted.
- Learn self-esteem, optimism, agreeableness, and conscientiousness.
- Write about things you are grateful for.
- Find a life purpose to live and a fulfilling job.
- Join a religious community.
- Find a good romantic partner and do novel things together.
- Exercise outside, achieve flow, and practice mindfulness.
- Avoid consumeristic buying habits.
These together look like a massively strong case in favor of B and against C and E. On the other hand, that list is so totally cheating. Those are the results of the studies which deliberately searched for and found interventions you could DO to improve happiness. But at the same time, happiness can also be improved by:
- Living in a happier city. (Favors E, and somewhat B, over C.)
- Antidepressants. (Favors C moderately over B and strongly over E.)
Also, we need to consider the things that surprisingly don’t seem to affect happiness set-points.
- Age. (Favors C somewhat over B and more over E.)
- Gender. (Favors C somewhat over B and strongly over E.)
- Parenthood. (Favors C strongly over B and E.)
- Intelligence. (Favors B weakly over C and E.)
- Physical attractiveness. (Favors C weakly over B and E.)
- Money over the poverty line. (Favors B strongly over C and E.)
Well shit. After all that, I’m going with the null hypothesis. Colorfully phrased: Shit happens; also you can do shit; but you probably can’t change how much you want to do shit. Conceivably, you may be able to alter the motivation level with diet and pharmaceuticals. Tentatively, I’m converting the idea of the hedonic set-point, so that the set-point doesn’t ensure a specific level of happiness so much as ensure your level of motivation. It predicts that when you exhaust your available intrinsic motivation, you will not be able to carry through on the things you theoretically want to do, and that when you’ve got an excess of unused motivation you’ll start finding things to do that you theoretically don’t want to do. It’s a bit like spoon theory, except that if you have too many unused spoons they’ll start force-feeding you.
This theory also makes sense of the known happiness by commitment mechanism.
- A fulfilling job that you are also financially obligated to keep doing.
- Personal projects that you do in collaboration so that you have social pressure to keep up on them.
- A romantic partner with whom you are reciprocally obligated to lavish personal attention on, and enjoy fun, romantic, intimate, and sexy times with, and comfort in times of sorrow and pain.
- Friends with whom you feel some reciprocal social obligation to keep up with.
- Anniversaries, birthdays, and holidays that you’re socially obligated to put happy-making effort into.
- A community (e.g. religious/philosophical, sports club, political activist association, etc.) with shared values that also enables and pushes you to learn and practice extroversion, self-esteem, optimism, agreeableness, conscientiousness, and gratitude.
- A geographic location with weather conducive to the outdoors activities you enjoy and proximity to places to do them, and where you can’t help but encounter opportunities for fulfilling work, romance, friendship, and community.
- A home arranged to minimize the burden of starting work so that you can’t easily avoid getting your projects done.
In each case, your intrinsic motivation for a task that is important to you may have been used up, but you’re being threatened with Consequences, so you work up the gumption to do them. And you’re happier as a result.