数学家研究纯数学不是因为它有用;他研究它是因为他喜欢它,他喜欢它是因为它美丽。
The mathematician does not study pure mathematics because it is useful; he studies it because he delights in it and he delights in it because it is beautiful.
I don't need a reason to be confident in my choices.
The only way to learn a new programming language is by writing programs in it.