Happiness is a state of well-being, or living a good life. Or something like that; in fact it is a fuzzy concept. But everyone wants to be happy, apparently, and sometimes happiness is described as “that at which everything aims”, and as synonymous with “good”1.
It is said that money don’t matter as much after a certain point, what roughly corresponds to the Maslow’s hierarchy of needs, though a lot of psychology is fraud and pseudoscience, and this particular theory should not be trusted easily. The wikihow’s “3 Ways to Be Happy” article (don’t get excited: those advices rarely work) points out that people are pretty flexible, and they can adapt to all kinds of things – both good and bad ones. And since happiness seems to go up when something gets better, but to decline afterwards, you are basically doomed to go back to the base level level of happiness, unless you change stuff around all the time, maintaining those happiness bumps, or unless you live in poverty or something like that. It also suggests that a lot of happiness depends on human interaction, which is unfortunate.
Most of stories (books and movies) which feature happy endings exploit that: they picture how a protagonist achieves happiness (gets out of trouble, achieves something that makes him or her, or whatever pronoun that person prefers, happy), and that’s where the stories should end – since there is gradual decoy right after that. Unless the said happy-ending is suicide or something like that, of course. You may have observed similar effects with toys, hardware, probably relationships, and all the other kinds of nice things which tend to make people happy: initial excitement turns into routine, and then you throw stuff (or people) away.
Being unhappy most of the time may be quite useful for doing some increasingly cool things, since it pushes one to improvement, unless it brings you depression, apathy, or something else along those lines. The latter seems to be similar to Nirvana, which some folks are trying to achieve, though probably it is different somehow – since people don’t seem to strive for apathy. But anyway, when you achieve or learn something, quite soon you stop considering it being that cool, and look for new stuff, or desire for more; in the end you lose, dying unsatisfied (and often old). That is, unless your last desire was to die, or you were apathetic in the end – but such cases are rarely associated with being happy, though may be associated with being calm (and, well, perhaps that Nirvana thing).
Since the race with ever-growing desires is more or less impossible to win, especially in the constantly changing and worsening world we live in, two strategies are often proposed: to fight those desires, or to use some tricks that are supposed to change your perception of reality – which mostly coincide with defence mechanisms. They will not lead to everlasting happiness, but may help to achieve contentment, which may also be pretty nice – though will probably eliminate even occasional happiness. To check how being calm works for you, you can simply wait until you will get sleepy and relaxed (warning: this may be addictive and lead to waste of time). It is trickier with happiness, but if you can’t even think of a way to invoke it – some drugs may assist, or simply remembering your dreams may help: though there is a lot of weird and scary stuff, one may also be genuinely happy in a dream. By the way, daydreaming is a weaker alternative.
Perpetual change may work, though it is also quite possible that you will get used to that, and may not always be possible to maintain and desire a perpetual change of positive things.
All in all, prolonged periods of happiness do not seem to be practically achievable, though one may hope for some glimpses of it.
Nicomachean Ethics provides an interesting perspective. Though some parts of it may sound rather weird and vague, it is short: paper wasn’t yet invented at the time of writing.↩