( CNN ) -- Paul J. Zak is the founding Director of the Center for Neuroeconomics Studies and Professor of Economics , Psychology and Management at Claremont Graduate University . He is the author of The Moral Molecule : The Source of Love and Prosperity . Evolution does not promote happiness . Most creatures live on the edge of survival and do whatever it takes to get through another day . Yet , many human beings seek to be , and often are , happy . How did that happen ? I spent a decade running neuroscience experiments to understand why humans are , much of the time , moral . We expect others to be honest , trustworthy , and kind and are outraged when they are not . As I report in my recent book The Moral Molecule : The Source of Love and Prosperity , my experiments showed that a then largely-ignored brain chemical in humans , oxytocin , motivates moral behaviors . Oxytocin does this by producing the feeling of empathy : When we are emotionally connected to others we tend to treat them well . My studies showed this was true even between complete strangers . Over 2,000 years ago , Aristotle claimed that morality comes from being in community with others . My experiments confirm this . Aristotle also argued that practicing virtue made one happy . I decided to put this to the test . I found that individuals who release the most oxytocin -- I call them `` oxytocin-adepts '' -- were more satisfied with their lives compared to those who release less oxytocin . Why ? They had better relationships of all types : Romantic , friendships , family , and they even shared more money with strangers in laboratory experiments . The moral molecule morphed in the happy molecule . Happiness largely comes from other people for social creatures like us . The logic step was to see if I could hack the happiness molecule . There is evidence in animals that repeated release of oxytocin biases the brain to release it more easily . In other words , it might be possible to become and oxytocin-adept . I began by refusing to shake hands . My experiments had shown that touch causes the release of oxytocin , so I replaced the handshake with a hug . Yes , for everyone , even on a first meeting . I found that after an embrace people opened up and connected to me much better than before I started this practice . My second hack was spending an extra second looking at people 's faces and then telling them what I saw . `` Hi Laura , you look sad today , are you OK ? '' Or , `` Hi Jorge , you really look happy , tell me what you 've been doing ? '' People appreciated my focus on how they felt and conversations went from the superficial to what really mattered . I was practicing empathy . My third hack was the most difficult . Oxytocin is sometimes called the `` love chemical '' because it sustains bonds between romantic partners and between parents and children . I decided to tell my friends and colleagues that I loved them . The response was overwhelming . Everyone lit up , some cried , everyone returned the love in words and deeds . I even earned the nickname `` Dr . Love . '' Did I really hack the happiness molecule ? I certainly feel much more connected to those around me , more open to emotional experiences , and , well , happier . I recently turned 50 and I was amazed when I had four surprise birthday parties on the same day . I think my brain hacks have made me a better friend , father , and colleague . Rich social networks extend life and improve health , so you might want to try to hack your oxytocin , too . Here 's your to-do list : Give eight hugs a day , focus on how those around you feel , and yes , use the `` L '' word when you can . If you find these difficult , start using them on a dog . My experiments have shown dogs are better oxytocin stimulators than other pets , and better stress-reducers , too . One more suggestion : Last year I decided to end every conversation with the word `` service , '' as in , `` I am at your service . '' If I 'm in a meeting , the person I 'm with wants something from me . My new hack is to give others what they want generously whenever possible . Nearly everyone is surprised and pleased by this and I typically get back much more than I have offered . I 'm an introvert who learned to revel in community . If you can hack the happiness molecule like I have , then I 've been of service . And that makes me happy . The opinions expressed in this commentary are solely those of Paul J. Zak .
Paul J. Zak : I spent a decade trying understand why humans are usually moral . His new book reports how brain chemical oxytocin motivates moral behaviors . He also tests Aristotle 's theory that practicing virtue made one happy . Comment: