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.
- A Martian taxonomist who didn't know that all human races happily interbreed with one another, and didn't know that most of the underlying genetic variance in our species is shared by all races might be tempted by our regional differences in skin colour, facial features, hair, body size and proportions to split us into more than one species.
- The descriptive analyst must be guided by certain very fixed principles if he is to be objective in describing accurately any language or part of any language. It would be excellent if he could adopt a completely man-from-Mars attitude toward any language he analyzes and describes.
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:
- I will not here argue that simplicity is relative, or that it is hard to define, or that a Martian might find the quus function simpler than the plus function.
In a common rhetorical turn, invoking the Martian scientist forces the reader to observe an obvious state of affairs that is ordinarily overlooked:
- If a Martian graced our planet, it would be struck by one remarkable similarity among Earth's living creatures and a key difference.
(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.)
American Martian scientists
Extraordinary World War II era Hungarian scientists who emigrated to the United States in the early half of the 20th century.   The most prominent Martians (scientists) included Theodore von Kármán, John von Neumann, Eugene Wigner, and Edward Teller. They were referred to as Martians due to their brilliant problem solving and invention talents that seemed out-of-this world .
- Dawkins R. A Devil's Chaplain: Selected Essays. Phoenix, London: Weidenfeld & Nicolson; 2003. ISBN 0-297-82973-4
- Nida E. Morphology: the descriptive analysis of words. 2nd ed. Ann Arbor: University of Michigan Press; 1949. p 1.
- Kripke, Saul. Wittgenstein on Rules and Private Language: An Elementary Exposition, Harvard University Press. p. 38
- Hauser MD, Chomsky N, Fitch WT. The Faculty of Language: what is it, who has it, and how did it evolve? Science. 2002;298(5598):1569-79. doi:10.1126/science.298.5598.1569 PMID 12446899
- M. Whitman (2012) The Martian's Daughter: A Memoir, University of Michigan Press.
- György Marx (2000). A Marslakók Érkezése (Arrival of the Martians). Hungary: Akadémiai Kiadó. p. 456. ISBN 963-05-7723-2.
- Hargittai, István (2006). The Martians of Science: Five Physicists Who Changed the Twentieth Century. USA: Oxford University Press. p. 376. ISBN 978-0-19-517845-6.