唯一真正有价值的东西是直觉。

出自汉·桓宽《盐铁论·力耕》。非，不是。宝，这句话指好的办法。道，途径、方法。治家并不是只有一种有效的方法，治国并不是只有一条可行的途径。这句话言治家与治国一样，都有许多不同的方法，当事人应当努力寻求，不必因循守旧而无所作为。

数学家们至今徒劳地试图在素数序列中发现某种规律，我们有理由相信这是一个人类思维永远无法穿透的谜题。

In mathematics, the simplest questions often lead to the deepest insights.

The melancholy science from which I make this offering to my friend relates to a region that from time immemorial was regarded as the true field of philosophy, but which, since the latter's conversion into method, has lapsed into intellectual neglect, sententious whimsy, and finally oblivion.