Abstract
Berkeley’s “selective attention” account of how we establish general conclusions without abstract ideas—particularly in light of his denial of abstract ideas and rejection of the legitimacy of several subjects of scientific and philosophic study on the grounds that they presuppose abstract ideas—yields a puzzle: Why can’t we begin with ideas and use the method of selective attention to establish conclusions about qualities and material objects independently of their being perceived, even though we do not have ideas of these entities? I argue that Berkeley’s reply depends partly on two doctrines that he suggests but does not develop explicitly: “Existing only when perceived” and “being inactive” are essential properties of ideas, and their status as essential means that they are included in the content of every idea. When conjoined with his account of representation, these doctrines leave us with no consistent cognitive surrogate that will allow us to think of qualities or material objects.