Where there is difficulty, there is strength.
52、一个人的价值和评价在于心灵与意志。
A person's value and evaluation lies in his mind and will.
53、没有错误的推论我们就无法推论。
We can't infer without wrong inferences.
54、世界上再没有比得到真理更困难的了。
Nothing in the world is more difficult than to get the truth.
55、学业才识，不日进，则日退。
Academic talent, not day advance, then retreat.
56、为学正如撑上船，一篙不可放缓。
Learning is like getting on a boat. A penny can't be slowed down.
57、困难是一个严厉的导师。
Difficulty is a stern mentor.
58、为伟大的事业捐躯，从来就不能算做失败。
To die for a great cause is never a failure.
