He who fights with monsters should be careful lest he thereby become a monster. And if thou gaze long into an abyss, the abyss will also gaze into thee.
Education consists mainly of what we have unlearned.
Blessed are the forgetful, for they get the better even of their blunders.
If you can't explain it to a six year old, you don't understand it yourself.
On the mountains of truth you can never climb in vain
The desire for a strong faith is not the proof of a strong faith, rather the opposite.