Martian scientist

A Martian scientist or Martian researcher is a hypothetical Martian frequently used in thought experiments as an outside observer of conditions on Earth. The most common variety is the Martian anthropologist, but Martians researching subjects such as philosophy, linguistics and biology have also been invoked.

The following extract from an essay by Richard Dawkins is more or less typical.

In American structuralist linguistics, the Martian approach is recommended for language description:

The hypothetical Martian anthropologist is described in the writings of Noam Chomsky as one who, upon studying the world's languages, would conclude that they are all dialects of a single language embodying a "universal grammar" reflecting a hardwired, genetically determined linguistic module inherent in the human brain.

In philosophy, especially philosophy of language and philosophy of mind, the Martian is often invoked as an example of an intelligent being with a cognitive apparatus that differs from that of humans, e.g. the following example given by Saul Kripke:

In a common rhetorical turn, invoking the Martian scientist forces the reader to observe an obvious state of affairs that is ordinarily overlooked:

(NB: The similarity Chomsky et al. mean is the universal hereditary language of DNA, while the difference is the lack of a universal language of communication.)

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