customed to see number, space, motion, believes that and nothing else?
90
Quod crebro videt non miratur, etiamsi cur fiat nescit; quod ante non viderit, id si evenerit, ostentum esse censet.[1] (Cic. 583.)
Næ iste magno conatu magnas nugas dixerit.[2]
91
Spongia solis.[3]—When we see the same effect always recur, we infer a natural necessity in it, as that there will be a to-morrow, &c. But nature often deceives us, and does not subject herself to her own rules.
92
What are our natural principles but principles of custom? In children they are those which they have received from the habits of their fathers, as hunting in animals. A different custom will cause different natural principles. This is seen in experience; and if there are some natural principles ineradicable by custom, there are also some customs opposed to nature, ineradicable by nature, or by a second custom. This depends on disposition.
93
Parents fear lest the natural love of their children may fade away. What kind of nature is that which is subject to decay? Custom is a second nature which destroys the former. But what is nature? For is custom not natural? I am much afraid that nature is itself only a first custom, as custom is a second nature.
