Pain past is pleasure.
［译］过去的痛苦就是快乐。
People who cannot find time for recreation are obliged sooner or later to find time for illness.
［译］腾不出时间娱乐的人，早晚会被迫腾出时间生病。
Perfect understanding will sometimes almost extinguish pleasure.
［译］完全的理解有时几乎会使乐趣消失。
Pleasure comes through toil.
［译］苦尽甘来。
Pleasure is nothing else but the intermission of pain, the enjoying of something I am in great trouble for till I have it.
［译］快乐不过是痛苦的间歇，享受之前要进行艰苦的努力。