Qualia

Qualia (singular: quale) is a term that philosophers use to describe the nature, or content, of our subjective experiences. What we are aware of when we see, hear, taste, touch or smell are our qualia. Explaining qualia is a fundamental topic in philosophy, but it has been argued that philosophers have not reached agreement upon a technical definition of the term (Dennett, 2005). For instance, to say that qualia are our subjective or phenomenal experiences requires technical definitions of what it is to be "subjective" or "phenomenal".

Explaining qualia is a key topic in philosophy because qualia are perhaps the most striking example of the Cartesian chasm between mind and body. For instance, while Chalmers (1996) notes the easy problems of explaining consciousness involve discriminating mental states, the hard problem of consciousness is explaining why conscious states are experienced as they are -- in short, the hard problem of consciousness is the explanation of qualia. Why should the processing of the brain give life to qualia at all?

References:

1. Chalmers, D. (1996). The conscious mind: In search of a fundamental theory. New York: Oxford University Press.
2. Dennett, D. C. (2005). Sweet Dreams: Philosophical Obstacles to a Science of Consciousness. Cambridge, MA.: MIT Press.

(Added March 2010)