 His argument for this conclusion turns on the first sentence of the passage, in which he claims that a species cannot represent an object to a cognizer unless the cognizer attends to the species. For Olivi, such attention to some thing is both a necessary and a sufficient condition for that thing’s being cognized. So if we do have to focus our attention in this way on species, he infers that those species will be the object of cognition, not merely causal intermediaries.