Let me begin by presenting two opposed conceptions of the relationship between the realm of the mental and our knowledge of this realm, neither of which is the conception I shall be supporting.

One I will call, with no pretension to scholarly accuracy, the Cartesian conception. According to this, the mind is transparent to itself. It is of the essence of mental entities, of whatever kind, to be conscious, where a mental entity's being conscious involves its revealing its existence and nature to its possessor in an immediate way. This conception involves a strong form of the doctrine that mental entities are “self-intimating,” and usually goes with a strong form of the view that judgments about one's own mental states are incorrigible or infallible, expressing a super-certain kind of knowledge which is suited for being the epistemological foundation for the rest of what we know.

The other is the view that the existence of mental entities and mental facts is, logically speaking, as independent of our knowing about them introspectively, and of there being whatever means or mechanisms enable us to know about them introspectively, as the existence of physical entities and physical facts is of our knowing about them perceptually, or of there being the means or mechanisms that enable us to have perceptual knowledge of them. This is the view that implies that our introspective self-knowledge should be construed in terms of what in my first lecture I called the broad perceptual model.