“He who tastes, knows; he who tastes not, knows not.” – Sufi Parable, superficially about coffee.
From Wikipedia’s post on “Qualia”:
Daniel Dennett identifies four properties that are commonly ascribed to qualia. According to these, qualia are:
- ineffable; that is, they cannot be communicated, or apprehended by any other means than direct experience.
- intrinsic; that is, they are non-relational properties, which do not change depending on the experience’s relation to other things.
- private; that is, all interpersonal comparisons of qualia are systematically impossible.
- directly or immediately apprehensible in consciousness; that is, to experience a quale is to know one experiences a quale, and to know all there is to know about that quale.
If qualia of this sort exist, then a normally sighted person who sees red would be unable to describe the experience of this perception in such a way that a listener who has never experienced color will be able to know everything there is to know about that experience. Though it is possible to make an analogy, such as “red looks hot”, or to provide a description of the conditions under which the experience occurs, such as “it’s the color you see when light of 700 nm wavelength is directed at you,” supporters of this kind of qualia contend that such a description is incapable of providing a complete description of the experience.
Another way of defining qualia is as “raw feels”. A raw feel is a perception in and of itself, considered entirely in isolation from any effect it might have on behavior and behavioral disposition. In contrast, a “cooked feel” is that perception seen as existing in terms of its effects.
According to an argument put forth by Saul Kripke in his paper “Identity and Necessity” (1971), one key consequence of the claim that such things as raw feels can be meaningfully discussed — that qualia exist — is that it leads to the logical possibility of two entities exhibiting identical behavior in all ways despite one of them entirely lacking qualia. While very few ever claim that such an entity, called a philosophical zombie, actually exists, the mere possibility is claimed to be sufficient to refute physicalism. Those who dispute the existence of qualia would therefore necessarily dispute the existence of philosophical zombies.
There is an ancient Sufi parable about coffee that nicely expresses the concept: “He who tastes, knows; he who tastes not, knows not.”
John Searle has rejected the notion that the problem of qualia is different from the problem of consciousness itself, arguing that consciousness and qualia are one and the same phenomenon.