There's a tendency to think that our present politicians are much worse than we had in the past.But we tend to forget how awful our politicians were in the past.

A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.

Running is not about being better than someone else. It's about being better than you used to be.

A good book should make you laugh, cry, and think.

每种心理状态都有其存在的目的；要理解它，我们必须询问它在更广泛的行为系统中发挥什么功能。