Relative happiness
I do not think that many people actively belief in absolute happiness, but nontheless we might not always be concious of the fact that happiness and knowning how to value certain priviliges –closely related to experiencing happiness– are derived by our minds by comparing. To make this more explicit I sometimes say: ‘If it was not for the vallies, we could not see the hills’.
As a consequence, people who do not know what war means, that is how nasty it is, they also do not know peace and hence its value. Of course everyone knows what war and peace are, but we all do on different levels of detail and abstraction. Some of us have lived during the way, others were born close to it, either in time or proximity, and thus have gotten to know the adverse effects through the people that did live in the way and yet others learn about in school or on the television. Paradoxically, those who have the least knowledge of war and the atrocities that it brings, seem to hold the least value for peace and the corresponding priviliges and rights that are necessary to maintain peace.
In a society where nobody ever gets ill, nobody values their health. A similar statement applies to experiencing happiness. It is hard to be happy when you always get what you want or –even worse– when you do not know what it means to be denied something. This is why we should actually value, at least partly, even the nastier things that happen to us, because they teach us how to appreciate all the rest.