It is a true observation of ancient writers, that as men are apt to be cast down by adversity, so they, are easily satiated with prosperity, and that joy and grief produce the same effects. For whenever men are not obliged by necessity to fight they fight from ambition, which is so powerful a passion in the human breast that however high we reach we are never satisfied.
Niccolo Machiavelli....for friendships that are acquired by a price and not by greatness and nobility of character are purchased but are not owned, and at the proper moment they cannot be spent.
Niccolo Machiavelli