Ecc 7:12 For wisdom is for a protection [the same as] money is for a protection; but the advantage of knowledge is that wisdom itself preserves alive its owners.
While happiness is not proportional to income, living near or below the poverty line can really raise the stress levels. Having a nest egg can give a little peace of mind. I've never understood the kind of people who don't like to see others get on in life. I've seen it go beyond jealousy to sheer maliciousness. It speaks volumes about the kind of bitter and twisted souls out there.