And think about subtracting off a variable amount lambda from each diagonal entry.

考虑从每个对角线元素中减去一个变量量。

This really fits into irresponsible reading, reading widely, reading a variable amount of literature which again as of the commonplace book helps with synoptic thinking.

这适用于非专业性阅读，你需要广泛阅读，阅读不同数量的文学作品，抱着读一本普通的书的心态，这有助于概要性思维。