"Should it be said that, from a number of uniform experiments, we infer a connection between the sensible qualities and the secret powers, this … seems the same difficulty, couched in different terms." (P 176b)

"The question still recurs, on what process of argument this inference is founded? Where is the medium, the interposing ideas, which join propositions so very wide of each other?" (P 176b)

"It’s always been that way" does not entail "it will always be that way."

"[T]he inference is not intuitive; neither is it demonstrative. . . . To say it is experimental, is begging the question." (P 176)