学无止境，一生的时间都嫌太短，所以古人皓首穷经，头发白了还是在继续研究，不过在这样的研究中确是有浓厚的趣味。

Art is long, life is short. That is why some of our ancients continued to study classics into their old age. They were, of course,motivated by an enormous interest in their studies.