Happiness is the evolutionary carrot on a stick.
Happiness is ephemeral, impermanent; a transient state.
Happiness is attained by fulfilling biologically advantageous objectives.
How to be happy:
2) have sex/kids
3) gain power/status (derivative of 1 and 2)
Contentment is lost upon self-reflection and self-awareness.
Contentment is a stable state of inner equilibrium.
Contentment is attained by unhooking biological imperatives.
How to be content:
1) forget self
2) don't try to be happy
3) empty the mind (derivative of 1 and 2)