Demosthenes

There are all kinds of devices invented for the protection and preservation of countries: defensive barriers, forts, trenches, and the like... But prudent minds have as a natural gift one safeguard which is the common possession of all, and this applies especially to the dealings of democracies. What is this safeguard? Skepticism. This you must preserve. This you must retain. If you can keep this, you need fear no harm.

Demosthenes

Small opportunities are often the beginning of great enterprises.

Nazim Hikmet

Living is no laughing matter:
you must live with great seriousness
like a squirrel, for example-
I mean without looking for something beyond and above living,
I mean living must be your whole occupation.