Whereas in the desire for wealth and for whatsoever temporal goods, the contrary is the case: for when we already possess them, we despise them, and seek others: which is the sense of Our Lord's words (Jn. 4:13):
‘Whosoever drinketh of this water," by which temporal goods are signified, ‘shall thirst again.’ The reason of this is that we realize more their insufficiency when we possess them: and this very fact shows that they are imperfect, and the sovereign good does not consist therein.
Now, as LiveScience.com reports, it seems that the the world might have caught up with St. Thomas in the results of a study published in the June 30 issue of the journal Science which reveal that income plays a rather insignificant role in day-to-day happiness. While there are some limitations to the survey base (notably that it was limited to women), “the correlation between income and life satisfaction is weak.”
Or, as St. Thomas Would put it, “All things salable can be had for money: not so spiritual things, which cannot be sold. Hence it is written (Prov. 17:16): ‘What doth it avail a fool to have riches, seeing he cannot buy wisdom.’” Or happiness.