The important things are always simple.
(Reply on what constitutes scientific proof:)"The question is much too difficult for me.
I don't teach my students, I provide the circumstances in which they can learn.
Whoever is devoid of the capacity to wonder, whoever remains unmoved, whoever cannot contemplate or know the deep shudder of the soul in enchantment, might just as well be dead for he has already closed his eyes upon life.
You cannot prepare for war and peace at the same time.
Everyone has two choices. We're either full of love... or full of fear.