Perception is basic for human knowledge and a major concern of both epistemology and the philosophy of mind. The scholarship in this area, however, has left two important aspects of perception underexplored: its relevance to understanding a priori knowledge-traditionally conceived as independent of perception-and its role in human action. This book provides a full-scale account of perception, a theory of the a priori, and an account of how perception guides action. In exploring perception and action, it clarifies the relation between action and practical reasoning, the notion of rational action, and the relation between knowledge of the practical (of how things are done) and practical knowledge (knowing how to do things).

In the first part of the book, Robert Audi lays out a theory of perception as experiential, representational, and causally connected with its objects. He argues that perception is a discriminative response to its objects; it embodies phenomenally distinctive elements; and it yields rich information that underlies human knowledge. Part Two presents a theory of self-evidence and the a priori. Audi's theory is perceptualist in that it explicates the apprehension of a priori truths by articulating its parallels to perception. The theory also unifies empirical and a priori knowledge by clarifying their reliable causal connections with their objects-connections many have thought impossible for a priori knowledge. The final part explores how perception guides action, the role of propositional knowledge in our abilities to do what we know how to do, the nature of reasons for action, the role of inference in determining it, and the overall conditions for its rationality. Addressing longstanding questions left unaddressed in the current literature, Audi's comprehensive theory of perception will appeal to scholars and students interested in philosophy of perception, mind, and epistemology.

Preface and acknowledgments
Introduction
Part One: Perception
Chapter 1 Perception and Perceptual Belief:
Seeing and Knowing the Physical World
I. Perception Broadly Conceived
II. Four Structurally Distinct Cases of Perception
III. The Representational Character of Perception
Chapter 2 Dimensions of Perceptual Content
I. Three Categories of Perceptual Content
II. Singular Reference and the Possible Role of Russellian Propositions
III. Perception and Belief: Cognitive and Conceptual Aspects
Chapter 3 Perceptual Levels and their Action-Theoretic Counterparts
I. Perception and Action: the Structural Analogy
II. Constitutive Elements in the Visual Perception of Physical Objects
III. Awareness of Events and Abstract Entities
IV. The Epistemological Significance of Perceptual Levels
V. Is Perception Theory-laden?
VI. The Importance of "Background Beliefs" and Perceptual Levels
VII. Aspectual Perception, Inference, and Recognition
Chapter 4 Perception as a Source of Knowledge and Justification
I. Perceptual Knowledge
II. The Hierarchical Character of Perception
III. Perceptual Justification: External and Internal Dimensions
IV. The Perceptibility of Normative Properties
Chapter 5 Reasons, Perceptual Grounds, and Normative Explanation
I. The Diversity of Reasons for Belief
II. Reasons as Distinguished from Grounds
III. Reasons and Grounds for Belief: The Practical Analogy
IV. Reasons as Explanations
V. Normative Reasons and their Grounds
Chapter 6 The Autonomy of Justification
I. Epistemological Internalism
II. Does Knowledge Entail Justification?
III. The Practice-Relativity of Justification
IV. An Integrated View of Knowledge and Justification
V. The Disjunctivist Challenge
VI. The Elusive Notion of the Content of Perceptual Belief
VII. Perception and Singular Reference
Part Two: Perception and the A Priori
Chapter 7 Perception, Intuition, and Apprehension
I. Perception and Intuition
II. Structural Parallels between Intuitional and Perceptional Discourse
III. Intuitions as Evidential Cognitions: Two Intuitionist Traditions
IV. Intuitions as Apprehensions
Chapter 8 Toward a Theory of the A Priori
I. The Concept of Self-Evidence
II. Understanding as Central for Knowledge of the Self-evident
III. Understanding and Imagination
IV. Major Elements in the Understanding of Propositions
V. Degrees of Understanding and Propositional Justification
VI. Comprehensional Adequacy
VII. Obstacles to Comprehension
Chapter 9 Apriority, Disputability, and Necessity
I. Self-Evidence and Provability
II. Can Rational Disagreement Extend to the Self-Evident?
III. The Self-Evident, the Obvious, and the Credible
IV. Apprehension of Abstract Entities
V. Apriority and Necessity
Part Three: Practical Knowledge
Chapter 10 Knowledge, Belief, and Action
I. Belief and Action
II. Two Orders of Cognitive Disposition
III. Belief and Knowledge, Intention and Action
Chapter 11 Knowing, Reasoning, and Doing
I. Intellectualism as a Perspective on Action
II. Practical Knowledge and Knowledge of the Practical
III. Virtual Knowledge: A Neglected Category
IV. The Place of Knowledge in Practical Reasoning
Chapter 12 Inference and Its Role in Rational Action
I. Inference and Inferential Belief
II. Inference, Reasoning, and Premise-Based Belief-Formation
III. Reasoning and Rational Action
IV. The Scope of Rational Action
V. Intentionality, Knowledge, and Agency
Conclusion