Abstract
Knowledge is a highly valued state in which a person is in cognitive contact with reality. It is, therefore, a relation. On one side of the relation is a conscious subject, and on the other side is a portion of reality to which the knower is directly or indirectly related. While directness is a matter of degree, it is convenient to think of knowledge of things as a direct form of knowledge in comparison to which knowledge about things is indirect. The former has often been called knowledge by acquaintance since the subject is in experiential contact with the portion of reality known, whereas the latter is propositional knowledge since what the subject knows is a true proposition about the world. Knowing Roger is an example of knowledge by acquaintance, while knowing that Roger is a philosopher is an example of propositional knowledge. Knowledge by acquaintance includes not only knowledge of persons and things, but also knowledge of my own mental states. In fact, the knower's own mental states are often thought to be the most directly knowable portion of reality.