Epicurus' Tetrapharmakos

Recipe for leading the happiest possible life from ~300 BC.

Don't fear god,
Don't worry about death;
What is good is easy to get, and
What is terrible is easy to endure

"Epicurus believed that the greatest good was to seek modest pleasures in order to attain a state of tranquility and freedom from fear (ataraxia) as well as absence of bodily pain (aponia) through knowledge of the workings of the world and the limits of our desires. The combination of these two states is supposed to constitute happiness in its highest form."