Our definition of happiness includes all the other things that people commonly think of as the good virtue, prudence, wisdom, pleasure, etc. Noble actions are inherently pleasant to a virtuous man. The good, the noble and the pleasant are all interconnected, because they all go along with the best activities, the best of which is happiness. Happiness also requires a minimal amount of external goods. The end of politics is the highest good, and consequently politics must try to cultivate dispositions to noble actions in citizens.
Happiness consists in a complete life lived according to virtue.
It is difficult to say whether the happiness of a person after death should depend on the fortunes of his descendants. Another difficulty is that a noble person may suffer external misfortunes which lessen his happiness. However, a virtuous person will endure misfortunes much better than an ignoble one. Therefore regardless of external circumstances no happy person will ever wretched, because to be wretched one must do something hateful or bad. Happiness is the principle of actions and the cause of all good things.