Nature is the best guide, and he that follows her, though he may sometimes go astray, yet will he be in the right way in the main.
自然是最好的向导，追随她的人，虽然有时可能会迷路，但总体上会走在正确的道路上。
The most profound insights in mathematics often come from unexpected analogies.
The first duty of the sovereign， that of protecting the society from the violence and invasion of other independent societies， can be performed only by means of a military force.
The only sensible ends of literature are, first, the pleasurable toil of writing; second, the gratification of one's family and friends; and lastly, the solid cash.