Whether classifiers (C) and measure words (M) can be meaningfully distinguished in Chinese has been a controversial issue, reflected also by the drastic discrepancy in the inventories of classifiers previously proposed. The two tests, i.e. de-insertion and adjectival modification, that proponents for the C/M distinction proposed have been shown to be unreliable and thus rejected. We re-examine these two tests closely and propose two sets of refined, reliable, and revealing tests. We further employ the Aristotelian distinction between essential and accidental properties as well as the Kantian distinction between analytic and synthetic propositions to characterize the C/M distinction. M is therefore semantically substantive and thus blocks numeral quantification and adjectival modification to the noun; C, in contrast, does not form such a barrier, for it is semantically null in the sense that it merely highlights a semantic aspect inherent to the noun and thus contributes no additional meaning.