If you want to truly understand something, try to change it.

If you want truly to understand something, try to change it.

I understand with love comes pain, but why did I have to love so much?

There is nothing so practical as a good theory

A successful individual typically sets his next goal somewhat but not too much above his last achievement. In this way he steadily raises his level of aspiration.

Learning is more effective when it is an active rather than a passive process