每一次的努力都是对未来的投资，智者明白这一点。

If you can dream it, you can achieve it.

那是一次非常短暂的访问，可是它却使小王子陷入深深的沮丧。

"A key insight in computational learning theory is that the complexity of a learning problem is determined by the complexity of the hypothesis space and the amount of data available."