Philosophical razor

In philosophy, a razor is a principle or rule of thumb that allows one to eliminate (shave off) unlikely explanations for a phenomenon, or avoid unnecessary actions. ^[1]

• Alder's razor (also known as Newton's flaming laser sword): If something cannot be settled by experiment or observation, then it is not worthy of debate. ^[2]
• Grice's razor (also known as Guillaume's razor): As a principle of parsimony, conversational implicatures are to be preferred over semantic context for linguistic explanations. ^[3]
• Hanlon's razor: Never attribute to malice that which can be adequately explained by stupidity. ^[4]
• Hitchens' razor: That which can be asserted without evidence can be dismissed without evidence. ^[5]
• Hume's guillotine: What ought to be cannot be deduced from what is; prescriptive claims cannot be derived solely from descriptive claims, and must depend on other prescriptions. "If the cause, assigned for any effect, be not sufficient to produce it, we must either reject that cause, or add to it such qualities as will give it a just proportion to the effect." ^[6]
• Occam's razor: Explanations that require fewer unjustified assumptions are more likely to be correct; avoid unnecessary or improbable assumptions.
• Popper's falsifiability criterion: For a theory to be considered scientific, it must be falsifiable. ^[7]
• Sagan standard: Positive claims require positive evidence, extraordinary claims require extraordinary evidence. ^[8]

See also

• Philosophy portal
• Psychology portal
• Science portal

• Abductive reasoning  – Inference seeking the simplest and most likely explanation
• Duck test  – Classification based on observable evidence
• Law of the instrument  – Over-reliance on a familiar tool
• Explanatory power  – Ability of a theory to explain a subject
• Marcello Truzzi § "Extraordinary claims"
• Morgan's Canon  – Law of parsimony in comparative (animal) psychology
• Morton's fork  – False dilemma in which contradictory observations lead to the same conclusion
• Russell's teapot  –Analogy formulated by Bertrand Russell to illustrate that the burden of proof lies upon a person making empirically unfalsifiable claims
• Occam's razor § Anti-razors
• Zebra (medicine)  – Exotic diagnosis in medicine which is usually unnecessary and wrong

References

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1. • Garg, Anu (17 May 2010). "Occam's razor". A.Word.A.Day. Archived from the original on 9 March 2014. Retrieved 25 February 2014.
   • Downie, R. S. (November 1989). "Moral Philosophy". In Eatwell, John; Milgate, Murray; Newman, Peter (eds.). The Invisible Hand. Palgrave MacMillan. pp. 213–222. ISBN   9781349203130.
   • McLean, Sheila A. M., ed. (2013). First Do No Harm: Law, Ethics and Healthcare. Ashgate. ISBN   9781409496199.
2. Alder, Mike (2004). "Newton's Flaming Laser Sword". Philosophy Now . 46: 29–33. Archived from the original on 4 December 2017. Retrieved 26 January 2018. Also available in PDF format: Alder, Mike (2004). "Newton's Flaming Laser Sword" (PDF). Mike Alder's Home Page. University of Western Australia. Archived from the original (PDF) on 14 November 2011.
3. • Hazlett, A. (2007). "Grice's razor". Metaphilosophy. 38 (5): 669. doi:10.1111/j.1467-9973.2007.00512.x.
   • "Implicature, 6: Gricean Theory". Stanford Encyclopedia of Philosophy. Archived from the original on 11 December 2016. Retrieved 27 December 2016.
4. "Hanlon's Razor". The Jargon File 4.4.7. Archived from the original on 30 April 2011. Retrieved 25 February 2014.
5. Ratcliffe, Susan, ed. (2016). Oxford Essential Quotations: Facts (4th ed.). Oxford University Press. ISBN   9780191826719 . Retrieved 4 November 2020. What can be asserted without evidence can also be dismissed without evidence.
6. • Miles, M. (2003). Inroads: Paths in Ancient and Modern Western Philosophy. University of Toronto Press. p.  543. ISBN   978-0802037442 – via Internet Archive.
   • Forrest, P. (2001). "Counting the cost of modal realism". In Preyer, G.; Siebelt, F. (eds.). Reality and Humean Supervenience: Essays on the Philosophy of David Lewis. Studies in Epistemology and Cognitive Theory. Rowman & Littlefield. p. 93. ISBN   978-0742512016 – via Google Books.
7. Popper, Karl (1972). The Logic of Scientific Discovery. Hutchinson. ISBN   9780091117207.
8. Sagan, Carl (2021). Broca's Brain: Reflections on the Romance of Science. New York: Ballantine Books. ISBN   978-0-345-33689-7.