Psychologists have been fond of stating in recent years that human happiness, or what psychologists call subjective well-being, is largely independent of our life circumstances. The wealthy aren’t much happier than the middle class, married people aren’t much happier than single people, healthy people aren’t much happier than sick people, and so on.
One might reasonably conclude, therefore, that changes in life circumstances would not have long-term effects on our happiness. This indeed has been the dominant model of subjective well-being: People adapt to major life events, both positive and negative, and our happiness pretty much stays constant through our lives, even if it is occasionally perturbed.