It certainly seems that we're going about our lives, that what we're doing, who we're with, what we're thinking about, have a big influence on our happiness, and yet these are the very factors that have been very difficult, in fact almost impossible, for scientists to study.
Ne trăim viețile, iar ceea ce facem, cu cine suntem, despre ce gândim, are mare influență asupra fericirii noastre. Totuși aceștia sunt exact factorii greu de cercetat, aproape imposibil, pentru oamenii de știință.