Newton’s first three rules offer a bold methodological program that attempts to unify science across different periods of space and time; it is a bet on the causal unity of nature. The maxim cautions against overconfidence in this regard. Hume’s caution is prophetic because it turns out that sub-atomic entities behave very differently than macroscopic bodies. However, it is not entirely certain if one should ascribe the “maxim” in the footnote to Hume because it is offered in the voice of a “fri