"Humans are designed to be sad, Happiness has no biological basis"

Just to add to my comment.. babies smile and are happy, it's one of the first things they do.. smile at people - this demonstrates the human capacity and ability re happiness..

The fact some Caliph wasn't happy isn't surprising, I was reading that the more material possessions we have, the more choices we have - the less satisfied we are..

I have always felt that being rich doesn't bring happiness either, perhaps related to the above, the more money you have, the more things you buy to try to make yourself happy, the more shallow and less genuine it all is..