This work argues for a Direct Realist view of the perception of public objects. It argues against the need for special intermediary sensory objects, or sense impressions, requiring only stages in a physical process beginning with events at the surface of a physical object, the resultant stimulation of one's sense organs, and finally the excitation of the sensory portions of one's brain.

This book offers a causal-explanatory account of knowledge as true belief caused by the worldly state of affairs that explains its existence. It also defends a contextual account of epistemic reasons, arguing that both foundationalism and coherentism cannot provide a satisfactory account of such reasons. Skeptical arguments are answered against a historical background from Plato to the present day.