's "An Enquiry Concerning Human Understanding" goes in depth into the reasoning behind cause and effect, something which we take for granted. His conclusion, that admits of no exception
, is that the knowledge of cause and effect is not arrived at through means of reasoning alone (a priori
His argument is that cause and effect are discovered not through reasoning, but through experience. It is through experience that we say we get burned when we touch fire.
"...In a word, then, every effect is a distinct event from its cause. It could not, therefore, be discovered in the cause, and the first invention or conception of it, a priori, must be entirely arbitrary. And even after it is suggested, the conjunction of it with the cause must appear equally arbitrary, since there are always many other effects, which, to reason, must seem fully as consistent and natural. In vain, therefore, should we pretend to determine any single event, or infer any cause or effect, without the assistance of observation and experience."
Principles of cause and effect are therefore arbitrary, arrived at through experiences of the world. This proposition has material implications. If cause and effect are arbitrary, then we may not be sure that A will cause B. You can say however, that in all previous instances of A, you have found B to occur. This knowledge would not be intuitive. It is arrived at through inference. One is inferring that all future occurences of A will be conjoined with B.
The moral is: human experience is arbitrary.