The beliefs and the unbeliefs are alike necessary, and alike erroneous.
It is commonly urged that the axiom of causation cannot be derived from experience, because experience only proves that many things have causes, whereas the axiom declares that all things have causes.

The syllogism, "many things which come into existence have causes, A has come into existence: therefore A had a cause," is obviously fallacious, if A is not previously shown to be one of the "many things." And this objection is perfectly sound so far as it goes.

The axiom of causation cannot possibly be deduced from any general proposition which simply embodies experience.

But it does not follow that the belief, or expectation, expressed by the axiom, is not a product of experience, generated antecedently to, and altogether independently of, the logically unjustifiable language in which we express it.
In fact, the axiom of causation resembles all other beliefs of expectation in being the verbal symbol of a purely automatic act of the mind, which is altogether extra-logical, and would be illogical, if it were not constantly verified by experience.

Experience, as we have seen, stores up memories; memories generate expectations or beliefs--why they do so may be explained hereafter by proper investigation of cerebral physiology.