真正的困难不在于构思新想法，而在于摆脱旧观念。
The real difficulty lies not in devising new ideas, but in escaping from the old ones.
時には、立ち止まって深呼吸することも必要だ。
The historian must be impartial, but not indifferent.
I never make the mistake of arguing with people for whose opinions I have no respect.