Seneca, On Tranquility of Mind IX

Your present opinion founded on understanding, your present conduct directed to social good, your present disposition contented with everything that happens — that is enough.

Everything you're trying to reach — by taking the long way round — you could have right now, this moment. If you'd only stop thwarting your own attempts.

Every nature is contented with itself when it goes on its way well; and a rational nature goes on its way well, when in its thoughts it assents to nothing false or uncertain.