Qualia are the qualitative contents of experience of our consciousness — that is, what it feels like to experience something. The redness of red, the pain of a toothache, the sweetness of a tone — all of these are qualia. They are immediately given, familiar to every experiencing subject, and yet in principle ungraspable by any quantitative, natural-scientific description. One can measure the wavelength of red light, but the experienced redness itself is no wavelength.
Two thought experiments have brought the philosophical significance of qualia especially vividly into view. Frank Jackson’s Mary’s room: a scientist knows all the physical facts about color vision but has herself never seen colors. When she sees red for the first time — does she then learn something new? If so, then there is a reality that is contained in no physical description. And Leibniz’s mill argument: even if one could enlarge the brain so as to walk about within it as in a mill, one would find there only parts that push against one another — but nowhere a perception, an experience, a quale. The interiority of experience cannot be assembled out of external mechanisms.
Qualia belong to the archphenomena — to those fundamental givens that cannot be further reduced to anything else but must be acknowledged if one is to do justice to the real. For the question of personhood they are of central importance: they show that the person possesses an interiority that discloses itself to no external perspective. Consciousness is not merely information processing but experiencing — and experiencing presupposes an experiencing someone.
Sources: Generated by querying the Personhood ontology.
Further sources:
- Nagel, Thomas (1974): “What Is It Like to Be a Bat?” The Philosophical Review 83(4), pp. 435—450.
- Jackson, Frank (1982): “Epiphenomenal Qualia.” The Philosophical Quarterly 32(127), pp. 127—136.
- Chalmers, David J. (1996): The Conscious Mind. In Search of a Fundamental Theory. Oxford: Oxford University Press.
- Leibniz, Gottfried Wilhelm (1714): Monadology, §17 (the mill argument).