 Penbygull (De universalibus, pp. 189–90) had (1) distinguished between the notion of non-identity and that of difference (or distinction); (2) denied that the notion of difference implies that of non-identity; (3) affirmed that the two notions of difference and real identity are logically compatible, thus admitting that (3.1) there are degrees in distinction, and (3.2) that the degrees of distinction between two things can be read as the inverse measure of their (partial) identity; and (4) suggested the following definitions for these three notions, that is non-identity, difference (or distinction), and (absolute) identity: (4.1) an entity a is non-identical with an entity b if and only if there is not any form F such that F is present in the same way in a and b; (4.2) an entity a differs from an entity b if and only if there is at least a form F such that F is directly present in a but not in b, or vice versa; (4.3) an entity a is absolutely identical with an entity b if and only if for any form F, it is the case that F is present in a if and only if it is present in the same way in b (see the entry on William Penbygull, §3).