  Albert attempted to formulate an answer to Porphyry’s famous problem of universals—namely, do the species according to which we classify beings exist in themselves or are they merely constructions of the mind? Albert appealed to his three-fold distinction, noting that a universal’s mode of being is differentiated according to which function is being considered. It may be considered in itself, or in  respect to understanding, or as existing in one particular or  another.[2]  Both the nominalist and realist solutions to Porphyry’s problem are thus too simplistic and lack proper distinction. Albert’s distinction thus allowed him to harmonize Plato’s realism in which universals existed as separate forms with Aristotle’s more nominalistic theory of immanent forms. For universals when considered in themselves (secudum quod in seipso) truly exist and are free from  generation, corruption, and  change.[3]  If, however, they are taken in reference to the mind (refertur ad intelligentiam) they exist in two modes, depending on whether they are considered with respect to the intellect that is their cause  or the intellect that knows them by  abstraction.[4]  But when they are considered in particulars (secundum quod est in isto vel in illo) their existence is exterior to as well as  beyond the mind, yet existing in things as  individuated.[5]