In the de Anima, Aristotle outlines a theory of perception. In de Anima II, 5-12, he considers the basic kinds of sensory perception — seeing, hearing, touching, tasting and smelling. He uses a few basic elements, viz., the five senses and their proper, common and incidental objects, and a few explanatory principles to explain sensory perception. In de Anima III, 1–2, Aristotle turns to apperception, viz. perceptual selfawareness. He considers several basic cases of apperception – the selfconscious awareness of occurrent perceptions and the awareness that the objects of different senses are different.