子曰：“后生可畏，焉知来者之不如今也？四十、五十而无闻焉，斯亦不足畏也已。”
【译文】 孔子说：“年轻人值得敬佩，怎知后代不如今人？四五十岁还默默无闻的人，就没什么前程了。”
You are never too old to set another goal or to dream a new dream.
You can tell whether a man is clever by his answers. You can tell whether a man is wise by his questions.
It is a curious subject of observation and inquiry, whether hatred and love be not the same thing at bottom.
The journey of scientific discovery is filled with challenges, but it is also incredibly rewarding.