The question is not whether the thing exists， but whether it has any essence which is capable of existence without us.
问题不在于事物是否存在，而在于它是否具有能够在没有我们的情况下存在的本质。
人心比山川更险恶，比了解天象更困难。
追求数学真理是一项崇高的努力。
Treating a person to a meal never fails， and is so easy to do. It’s powerful with old friends and a great way to make new friends.
预测未来的最好方法就是发明未来。
茍活比牺牲需要更多的勇气。