 Ockham’s theory of knowledge, like his natural philosophy, is broadly Aristotelian in form, although—again, like his natural philosophy—it is “Aristotelian” in its own way. For most Aristotelians of the day, knowledge involved the transmission of a  “species”[39]  between the object and the mind. At the sensory level, this species may be compared to the more recent notion of a sense “impression.” More generally, we can think of it as the structure or configuration of the object, a structure or configuration that can be “encoded” in different ways and found isomorphically in a variety of contexts. One recent author, describing the theory as it occurs in Aquinas, puts it like  this:[40]