This new paper by Alva Noë describes his action-oriented approach to perception. Interestingly, he discusses the “constancies” of perception quite a bit and disagrees with Sean Kelly’s account (discussed here) on some points. Whereas Kelly stresses two modes of perceptual attitude (the engaged and the detached), Noë views both ways of perceiving an object (with and without constancy) to be concurrent – a “two-dimensional” experience. I tend to prefer Kelly’s take on this. But much more important than these differences is what I take to be the two philosophers’ broad agreement on the main way to approach the problem of perception: that is, perception is grounded in bodily engagement with the world.
According to Noë, one’s relation to perceived elements of the environment is essentially sensori-motor. Even in the case of vision (which somewhat unfortunately dominates discussion of perception), our perception of objects is shaped by how we could move and probe the object in its environmental context. This is how we perceive the missing part of the object which is partly obscured behind a picket fence, and how we view the penny to be round despite its being turned at an angle which presents an elliptical image to the retina.
This approach is the best way to address the long-standing philosophical “problem of perception” discussed in this SEP article recently posted. Historically, different approaches to the problem suffered from explicitly or implicitly viewing perceptions as representations or other entities in the mind. Instead we should view perception as actually based on direct interaction with the world. How does this address the phenomena of illusion and hallucination? If perception is direct contact with the external world, how are these possible? Well, through other causes impacting our body/brain, it becomes as if we have the perception. But if we cut out the middle-man of sense-data or representations, the existence of illusions or hallucinations shouldn’t lead to radical skepticism about the reliability of normal perception.