Abstract
The causal representative theory of perception dominated theory of knowledge for hundreds of years after it was put on the map by Descartes and Locke. It is now almost extinct. How could this happen? The theory collapsed because it could not explain how we acquire knowledge of the external world, since it presupposes a causally organized system of external objects producing sensations in us. This presupposition, however, is generally recognized as true, so that the pattern of causal inference at the heart of the theory is surely justified. The theory cannot explain how we originally acquire our knowledge of the external world, but it is entitled on a second pass to correct our empirical beliefs, where necessary. This includes replacing our naive picture of the physical world with a more sophisticated scientific conception, which downgrades secondary qualities. This was, indeed, the main reason why it was originally introduced by Descartes and Locke, and has been the source of its attraction over the years.