Inverted spectrum

This MedLibrary.org supplementary page on Inverted spectrum is provided directly from the open source Wikipedia as a service to our readers. Please see the note below on authorship of this content, as well as the Wikipedia usage guidelines. To search for other content from our encyclopedia supplement, please use the form below:

Inverted spectrum is the apparent possibility of two people sharing their colour vocabulary and discriminations, although the colours one sees — their qualia — are systematically different from the colours the other person sees.

Inverted qualia

The argument dates back to John Locke1. It invites us to imagine that we wake up one morning, and find that for some unknown reason all the colors in the world have been inverted. Furthermore, we discover that no physical changes have occurred in our brains or bodies that would explain this phenomenon. Supporters of the existence of qualia argue that, since we can imagine this happening without contradiction, it follows that we are imagining a change in a property which determines the way things look to us, but which has no physical basis. In more detail:

  1. Metaphysical identity holds of necessity
  2. If something is not possibly false, it is not necessary
  3. It is conceivable that qualia could have a different relationship to physical brain-states
  4. If it is conceivable, then it is possible
  5. Since it is possible for qualia to have a different relationship with physical brain-states, they cannot be identical to brain states (by 1).
  6. Therefore, qualia are non-physical.

The argument thus claims that if we find the inverted spectrum plausible, we must admit that qualia exist (and are non-physical). Some philosophers find it absurd that an armchair argument can prove something to exist, and the detailed argument does involve a lot of assumptions about conceivability and possibility, which are open to criticism. Perhaps it is not possible for a given brain state to produce anything other than a given quale in our universe, and that is all that matters.

The idea that an inverted spectrum would be undetectable is also open to criticism on more scientific grounds:23

there are more perceptually distinguishable shades between red and blue than there are between green and yellow, which would make red-green inversion behaviorally detectable.[1 And there are yet further asymmetries. Dark yellow is brown (qualitatively different from yellow), whereas dark blue is blue[..] Similarly, desaturated bluish-red is pink (qualitatively different from saturated bluish-red), whereas desaturated greenish-yellow is similar to saturated greenish-yellow. Again, red is a “warm” color, whereas blue is “cool” — and perhaps this is not a matter of learned associations with temperature.

Inverted spectrum arguments have applications to behavioralism, physicalism, representationalism, functionalism, skepticism and the hard problem of consciousness.

In his book I Am A Strange Loop, Douglas Hofstadter argues that the inverted spectrum argument entails a form of solipsism in which people can have no idea about what goes on in the minds of others-- contrary to the central theme of his work. He presents several variants to demonstrate the absurdity of this idea: the "inverted political spectrum", in which one person's concept of liberty is identical to another's concept of imprisonment; an inverted "sonic spectrum" in which low musical notes sound like "high" ones and vice versa(which he claims is impossible because low sounds can be felt physically as vibrations); and a version in which random, complex qualia such as riding a roller coaster or opening presents are reversed, so that everyone perceives the world in radically different, unknowable ways.

Notes

  1. ^ (In this passage, Locke uses "idea" to mean something like "mental image", rather than its modern meaning. He also uses "texture" to mean the physical property that gives rise to a color-sensation) "Neither would it carry any Imputation of Falshood to our simple Ideas, if by the different Structure of our Organs, it were so ordered, That the same Object should produce in several Men's Minds different Ideas at the same time; v.g. if the Idea, that a Violet produced in one Man's Mind by his Eyes, were the same that a Marigold produces in another Man's, and vice versâ. For since this could never be known: because one Man's Mind could not pass into another Man's Body, to perceive, what Appearances were produced by those Organs; neither the Ideas hereby, nor the Names, would be at all confounded, or any Falshood be in either. For all Things, that had the Texture of a Violet, producing constantly the Idea, which he called Blue, and those which had the Texture of a Marigold, producing constantly the Idea, which he as constantly called Yellow, whatever those Appearances were in his Mind; he would be able as regularly to distinguish Things for his Use by those Appearances, and understand, and signify those distinctions, marked by the Names Blue and Yellow, as if the Appearances, or Ideas in his Mind, received from those two Flowers, were exactly the same, with the Ideas in other Men's Minds." Locke, J., 1689/1975, Essay Concerning Human Understanding, Oxford: Oxford University Press.
  2. ^ Inverted Qualia, Stanford Encyclopedia of Philosophy
  3. ^ Hardin, C. L., 1987, “Qualia and Materialism: Closing the Explanatory Gap”, Philosophy and Phenomenological Research, 48: 281-98.

See also

External links

Wikipedia content modification information:

  • This page was last modified on 24 July 2008, at 23:37.

Wikipedia Authorship and Review

Wikipedia content provided here is not reviewed directly by MedLibrary.org. Wikipedia content is authored by an open community of volunteers and is not produced by or in any way affiliated with MedLibrary.org.

Wikipedia Usage Guidelines

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Inverted spectrum".

The URL for this specific entry is:

All Wikipedia text is available under the terms of the GNU Free Documentation License. (See Copyrights for details). Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc.