时间被认为只有一个维度，而空间有三个维度。

学习算法的设计应同时受到理论见解和实践考虑的指导。

The world needs more scientists who think like engineers, and more engineers who think like scientists.

We are all travelers in the wilderness of this world, and the best we can find in our travels is an honest friend.

书本身不是目的，它是一种唤起的手段。

    ——杜先生晚年在香港，先生为中国抗战.赈灾慈善做出巨大贡献，晚年依旧气度过人，毁掉所有欠条。