english: 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.
non_english: Svakako deluje da utičemo na naše živote, da ono što radimo, sa kim smo, o čemu razmišljamo ima velikog uticaja na našu sreću, ali ipak ovo su razni faktori koji su bili veoma teški, zapravo skoro nemogući za proučavanje naučnika.