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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]

Razors include:

  • Occam's razor: Simpler explanations are more likely to be correct; avoid unnecessary or improbable assumptions.
  • Grice's razor: As a principle of parsimony, conversational implications are to be preferred over semantic context for linguistic explanations.[2][3]
  • Hanlon's razor: Never attribute to malice that which can be adequately explained by stupidity.[4]
  • Hume's razor: "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."[5][6]
  • Hitchens' razor: "What can be asserted without evidence can be dismissed without evidence."
  • Newton's flaming laser sword: If something cannot be settled by experiment or observation, then it is not worthy of debate.[7]
  • Popper's falsifiability principle: For a theory to be considered scientific, it must be falsifiable.
  • Sagan standard: Extraordinary claims require extraordinary evidence.
  • Rand's razor: Prior to philosophizing, the philosopher needs to identify their initial, irreducible, primary axioms.[8][9]

See alsoEdit


  1. ^ Garg, A. (17 May 2010). "Occam's razor". A.Word.A.Day. Archived from the original on 2014-03-09. Retrieved 2014-02-25.
  2. ^ Hazlett, A. (2007). "Grice's razor". Metaphilosophy. 38 (5): 669. doi:10.1111/j.1467-9973.2007.00512.x.
  3. ^ "Stanford Encyclopedia of Philosophy, Implicature". Implicature, 5. Gricean Theory. Archived from the original on 2016-12-11. Retrieved 2016-12-27.
  4. ^ "Hanlon's Razor". The Jargon File 4.4.7. Archived from the original on 2011-04-30. Retrieved 2014-02-25.
  5. ^ Miles, M. (2003). Inroads: Paths in Ancient and Modern Western Philosophy. University of Toronto Press. p. 543. ISBN 978-0802037442.
  6. ^ 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 Publishers. p. 93. ISBN 978-0742512016.
  7. ^ Mike Alder (2004). "Newton's Flaming Laser Sword". Philosophy Now. 46: 29–33. Archived from the original on 2017-12-04. Retrieved 2018-01-26.
    Also available as Mike Alder (2004). "Newton's Flaming Laser Sword" (PDF). Mike Alder's Home Page. University of Western Australia. Archived from the original on 14 November 2011.CS1 maint: unfit url (link)
  8. ^ Ryan, Scott (27 January 2003). "Appendix: Theism, Rationalism, and Objective Idealism". Objectivism and the Corruption of Rationality: A Critique of Ayn Rand's Epistemology. iUniverse. ISBN 978-0595267330. Retrieved 16 June 2019. ‘Rand’s Razor’—that is, ‘state your irreducible primaries’ [Journals of Ayn Rand, pp. 699-700]
  9. ^ Peikoff, Leonard (1993). Objectivism: The Philosophy of Ayn Rand. The Ayn Rand Library. VI. Meridian. p. 139. ISBN 0-452-01101-9. ‘Rand’s Razor’…Rand’s Razor is addressed to anyone who enters the field of philosophy. It states: name your primaries. Identify your starting points, including the concepts you take to be irreducible, and then establish that these are objective axioms. Put negatively: do not begin to philosophize in midstream. Do not begin with some derivative concept or issue, while ignoring its roots, however much such issue interests you.