Content and Consciousness

The book's argument is that the philosophy of mind has two main topics—content and consciousness—and that they must be addressed in that order. Dennett argues that a theory of intentionality, or mental content, is more fundamental than a theory of consciousness, because consciousness presupposes content rather than the reverse . The book develops this claim through a distinction between the 'personal' level, where we describe a subject as having beliefs and desires, and the 'sub-personal' level, where physiological mechanisms operate without consciousness . What Content and Consciousness rejects is the Cartesian assumption that consciousness is a unified inner domain requiring its own separate explanation. By showing that personal-level descriptions and sub-personal mechanisms answer different questions, Dennett argues the mind-body problem dissolves rather than requires a solution.

The distinction separates two levels of explanation. The personal level describes a whole organism in terms of beliefs, desires, and intentions—the vocabulary of everyday psychology. The sub-personal level describes the physiological and computational mechanisms that implement those capacities, none of which individually possesses beliefs or consciousness . Dennett argues that confusion arises when philosophers treat sub-personal mechanisms as if they were miniature persons, or when they demand that personal-level descriptions be reducible to sub-personal ones. The distinction allows cognitive science to study the brain's machinery without denying the reality of personal-level phenomena. In this book, Dennett treats the distinction as non-mechanistic: personal-level explanations render behavior intelligible, while sub-personal explanations describe how that intelligibility is physically realized.

Reception was unusually strong for a first book in technical philosophy. Thomas Nagel, reviewing in the Journal of Philosophy, called it 'a difficult work of technical philosophy that is such a pleasure to read,' praising its ambition and its effective use of scientific information . Richard Rorty, in Philosophical Studies, described it as 'an extraordinarily interesting and original book' that would 'raise the level of current discussion in the philosophy of mind' . J.J.C. Smart in Mind recommended it to anyone interested in the mind-body problem . The book was widely regarded as the foundation from which all of Dennett's later ideas developed, and it established him as a major voice in the emerging field of cognitive science .

The relationship is one of development and refinement. Dennett himself described his career as a series of recapitulations of the structure first laid out in Content and Consciousness: first a theory of content, then a theory of consciousness . The Intentional Stance (1987) is the second recapitulation of the content half of that program, developing the idea that we predict and explain behavior by adopting the 'intentional stance'—treating a system as if it had beliefs and desires. Content and Consciousness introduced the personal/sub-personal distinction and the idea that intentional descriptions are a distinct level of explanation; The Intentional Stance works out the implications of that idea in far greater detail. The later book presupposes the framework established in the earlier one.

The structure is not merely organizational but argumentative. Dennett's claim is that consciousness cannot be understood until we understand what it is for a state to have content—to be about something . This priority reverses the approach of many philosophers who begin with the phenomenology of conscious experience and then ask how it relates to the physical world. For Dennett, the intentional stance provides the vocabulary for describing what minds do, and consciousness is a further capacity that arises when certain content-bearing processes are organized in particular ways. The book's structure therefore enacts its thesis: any attempt to explain consciousness without first explaining content will be misguided. This methodological commitment shapes all of Dennett's subsequent work.

Content and Consciousness was first published in 1969 by Routledge & Kegan Paul in London and Humanities Press in New York, as part of the International Library of Philosophy and Scientific Method . A second edition appeared in 1986, with a new preface by Dennett that placed the book in the context of his more recent work . Routledge reissued it in 2010 as a Routledge Classics paperback, making the text widely available to a new generation of readers . The second edition includes the original text plus the 1986 preface, which is important for understanding how Dennett himself later viewed the book's arguments. The work has never been substantially revised, a sign of Dennett's confidence in its basic framework.