 The rule that terms can be listed as common ones if and only if they signify a common nature is safe, but at the cost of a counterintuitive categorization of their semantic power. In fact, according to Alyngton’s account, saying that Socrates and Plato are first substances simply means that (i) each one is what he is, and that (ii) what each one is is a non-universal substance. This is a solution that entails that to be an individual is not a positive state of affairs, but a negative one, and therefore connects Alyngton’s ontology with Henry of Ghent’s theory of individuation.