Success is not final, failure is not fatal: It is the courage to continue that counts.

The joy of discovery is what drives mathematicians forward.

Don’t let anyone dim your light.

解释：河流川泽中有污水，深山草野中藏有瘴气，美玉也有微小的瑕疵。

艺术是自由的科学。

如果没有机械的帮助，一天的劳动不足以生产一磅棉花。