子曰:“君子坦荡荡,小人长戚戚。”
【译文】 孔子说:“君子总是胸怀宽广,小人总是忧愁悲伤。”
To do mathematics is to explore a universe of ideas, where the only limit is your imagination.
The past does not equal the future.
People must feel that the natural world is important and valuable and beautiful and wonderful and an amazement and a pleasure.