Mind projection fallacy

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The mind projection fallacy is a logical fallacy first described by physicist and Bayesian philosopher E.T. Jaynes. It occurs when someone thinks that the way they see the world reflects the way the world really is, going as far as assuming the real existence of imagined objects.[1] That is, someone's subjective judgements are "projected" to be inherent properties of an object, rather than being related to personal perception. One consequence is that others may be assumed to share the same perception, or that they are irrational or misinformed if they do not.

For example, someone might informally claim that broccoli tastes bad, even though "taste" depends on one's taste buds and prior experience. Alternatively, we might conclude that intelligent aliens will value the same things we do or be driven by similar motivations, even though their minds may not be constructed in the same way.

A second form of the fallacy, as described by Jaynes,[1] is when someone assumes that their own lack of knowledge about a phenomenon (which is a fact about their state of mind) means that the phenomenon is not or cannot be understood (a fact about reality). (See also Map and territory.)

Jaynes used this concept to argue against Copenhagen interpretation of quantum mechanics.[2] He described the fallacy as follows:[1]

[I]n studying probability theory, it was vaguely troubling to see reference to "gaussian random variables", or "stochastic processes", or "stationary time series", or "disorder", as if the property of being gaussian, random, stochastic, stationary, or disorderly is a real property, like the property of possessing mass or length, existing in Nature. Indeed, some seek to develop statistical tests to determine the presence of these properties in their data...

Once one has grasped the idea, one sees the Mind Projection Fallacy everywhere; what we have been taught as deep wisdom, is stripped of its pretensions and seen to be instead a foolish non sequitur. The error occurs in two complementary forms, which we might indicate thus: (A) (My own imagination) → (Real property of Nature), [or] (B) (My own ignorance) → (Nature is indeterminate)

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  1. ^ a b c E. T. JAYNES (1989). "PROBABILITY THEORY AS LOGIC" (PDF). Ninth Annual Workshop on Maximum Entropy and Bayesian Methods. Retrieved 2011-05-19. 
  2. ^ Jaynes, E. T. (1989). "Clearing up Mysteries--The Original Goal". Maximum Entropy and Bayesian Methods: 7.