Whether happiness once had can be lost?

Objections

Objection 1 : It would seem that Happiness can be lost. For Happiness is a perfection. But every perfection is in the thing perfected according to the mode of the latter. Since then man is, by his nature, changeable, it seems that Happiness is participated by man in a changeable manner. And consequently it seems that man can lose Happiness.
Objection 2 : Further, Happiness consists in an act of the intellect; and the intellect is subject to the will. But the will can be directed to opposites. Therefore it seems that it can desist from the operation whereby man is made happy: and thus man will cease to be happy.
Objection 3 : Further, the end corresponds to the beginning. But man's Happiness has a beginning, since man was not always happy. Therefore it seems that it has an end.