Stories you read when you're the right age never quite leave you. You may forget who wrote them or what the story was called. Sometimes you'll forget precisely what happened, but if a story touches you it will stay with you, haunting the places in your mind that you rarely ever visit.
The use of a program to prove the 4-color theorem will not change mathematics - it merely demonstrates that the theorem, a challenge for a century, is probably not important to mathematics.
You have to be willing to fail, to be wrong, to keep pushing forward even when everyone tells you you're crazy.
墨子说:言论如果能够付诸行动的就可以讲;不能够付诸行动的就别多说。言论不能付诸行动的而常讲,这就是卖弄口才了。