"The fallacy of the "floating abstraction" is Ayn Rand's term for concepts detached from existents, concepts that a person takes over from other men without knowing what specific units the concepts denote." Source -- no Lexicon reference available.
A blind person may use equipment that emits different tone base on the color spectrum reflected by particular surfaces. However, since he is unable to experience "redness" directly, how would he "know" what the specific units are for the concept red?
asked Nov 27 '12 at 19:52
Not necessarily. If you try to use a concept when you have not ever observed any of its units, then the concept is floating to you. Thus, if the blind man tries to use the concept "red" without ever observing any of its units, then it is a floating abstraction to him. If, however, the blind man can observe the units and form a concept by integrating those units, then the concept is not floating to him.
The question then becomes, can a blind man ever observe the units that are integrated by the concept "red" as that concept is formed by most sighted people? If the units of "red" is merely light of a certain wavelength, then clearly a blind man can perceive these units and integrate them into a concept---he will have to perceive them indirectly since he cannot see (your sound machine is a good example), but that is perfectly okay.
If the units are not the light, but rather the state of perception itself, then perhaps the blind person could never observe the units. In that case, the blind person could observe that sighted people report experiencing a state XYZ in response to circumstance ABC, and from that form a concept that integrates these facts. This concept would be related to the sighted concept of "red" because it relates to the same underlying phenomenon, but the units of the blind person's concept may be qualitatively different enough from the sighted person's concept that we would consider them different--albeit related--concepts. In that case, the blind person's concept would be a concept about reported states of perception versus the sighted person's concept that would be about experienced states of perception.
answered Jan 09 '15 at 16:49
The source of the quote can be found in OPAR, p. 96, with a slightly condensed version excerpted in Ayn Rand's Glossary of Objectivist Definitions. Here is the OPAR version:
A concept ... is an integration that rests on a process of abstraction. Such a mental state is not automatically related to concretes, as is evident from the many obvious cases of "floating abstractions." This is Ayn Rand's term for concepts detached from existents, concepts that a person takes over from other men without knowing what specific units the concepts denote. [...]
From this description, I must conclude that "red" qualifies as floating for a blind man who tries to adopt it, because "red" is a very basic concept referring directly to sensations -- visual sensations of colors, which a blind man would have no way to experience, and thus no way to have any idea what people are talking about when they speak of colors. At most, a blind person might be able to conceptualize "seeing" by analogy to some other sensory modality which the blind man possesses. His ability to do this could also be influenced by whether or not he was blind from birth or became blind later in life, after some period (perhaps very brief) of being able to see.
Update: Machines to Extend Man's Senses
The comments mention the Munsell color system, instruments to measure the main attributes of color (hue, value, and chroma in the Munsell system), and the possibility of fitting such instruments with a converter of some kind that would allow a blind person to know the color measurements produced by the instrument, such as by touch (or hearing). This is a very good example of the kind of possibility that I had in mind when I briefly alluded to "red" as a valid high level abstraction for a blind person:
At most, a blind person might be able to conceptualize "seeing" by analogy to some other sensory modality which the blind man possesses.
("Analogy" isn't necessarily the best choice of wording here.) A similar possibility that has occurred to me is a machine that converts a visible color spectrum into a sound spectrum. The sound spectrum might consist of multiple tones of varying amplitudes, with each tone's frequency corresponding to a color, and the intensity of each tone corresponding to the intensity of that color. In effect, a blind person would be able to "hear" (as a sound spectrum) the colors that his instrument is detecting.
In that kind of context, a blind person's concept of "red" could, indeed, be completely objective, yet very different in form from a sighted person's concept deriving from direct perception. A blind person might be able to understand that light exists and has many possible colors, but he would not be able to experience what "seeing" and "red" are like to someone who can see and is not color blind (just as man can only try to project what it would be like to have the sense of smell possessed by dogs and bears, for example, or the sonar perception of porpoises).