A false dilemma (or sometimes called false dichotomy) is a type of informal fallacy, more specifically one of the correlative-based fallacies, in which a statement falsely claims an "either/or" situation, when in fact there is at least one additional logically valid option.
The false dilemma fallacy can also arise simply by accidental omission of additional options rather than by deliberate deception. For example, "Stacey spoke out against socialism, therefore she must be a fascist" (she may be neither socialist nor fascist or a socialist who disagrees with portions of socialism). "Roger opposed an atheistic argument against Christianity, so he must be a Christian" (When it's assumed the opposition by itself means he's a Christian). Roger might be an atheist who disagrees with the logic of some particular argument against Christianity. Additionally, it can be the result of habitual tendency, whatever the cause, to view the world with limited sets of options.
Some philosophers and scholars believe that "unless a distinction can be made rigorous and precise it isn't really a distinction". An exception is analytic philosopher John Searle, who called it an incorrect assumption that produces false dichotomies. Searle insists that "it is a condition of the adequacy of a precise theory of an indeterminate phenomenon that it should precisely characterize that phenomenon as indeterminate; and a distinction is no less a distinction for allowing for a family of related, marginal, diverging cases." Similarly, when two options are presented, they often are, although not always, two extreme points on some spectrum of possibilities; this may lend credence to the larger argument by giving the impression that the options are mutually exclusive, even though they need not be. Furthermore, the options in false dichotomies typically are presented as being collectively exhaustive, in which case the fallacy may be overcome, or at least weakened, by considering other possibilities, or perhaps by considering a whole spectrum of possibilities, as in fuzzy logic. This issue arises from real dichotomies in nature, the most prevalent example is the occurrence of an event. It either happened or it did not happen. This ontology sets a logical construct that cannot be reasonably applied to epistemology.
Common phrases expressing similar or synonymous concepts include:
- bifurcation fallacy
- black-or-white fallacy
- denying a conjunct (similar to a false dichotomy: see Formal fallacy § Denying a conjunct)
- either/or fallacy
- fallacy of exhaustive hypotheses
- fallacy of the excluded middle
- fallacy of the false alternative
- false binary
- false dichotomy
- false choice
- limited choice
- no middle ground
The presentation of a false choice often reflects a deliberate attempt to eliminate several options that may occupy the middle ground on an issue. A common argument against noise pollution laws involves a false choice. It might be argued that in New York City noise should not be regulated, because if it were, a number of businesses would be required to close. This argument assumes that, for example, a bar must be shut down to prevent disturbing levels of noise emanating from it after midnight. This ignores the fact that a law could require the bar to lower its noise levels, or install soundproofing structural elements to keep the noise from excessively transmitting onto others' properties.
In psychology, a phenomenon related to the false dilemma is "black-and-white thinking" or "thinking in black and white". There are people who routinely engage in black-and-white thinking, an example of which is someone who categorizes other people as all good or all bad.
- Degrees of truth
- Euthyphro dilemma
- Fallacy of the single cause
- Hobson's choice
- Law of excluded middle
- Lewis' trilemma
- Loaded question
- Love–hate relationship
- Many-valued logic
- Morton's fork
- Nolan Chart
- None of the above
- Pascal's Wager
- Political systems
- Rogerian argument
- Show election
- Slippery slope
- Sorites paradox
- Splitting (psychology)
- Strange loop § In cognitive science
- Straw man
- Thinking outside the box
- You're either with us, or against us
- "False Dilemma". Department of Philosophy, Texas State University.
- Jacques Derrida (1991) Afterword: Toward An Ethic of Discussion, published in the English translation of Limited Inc., pp. 123–24, 126
- Searle, John. (1983) The Word Turned Upside Down. The New York Review of Books, Volume 30, Number 16, October 27, 1983.
- Baronett, Stan (2008). Logic. Upper Saddle River, N.J.: Pearson Prentice Hall. p. 101. ISBN 9780131933125. Retrieved 31 October 2015.
- Arfi, Badredine (2010). Linguistic fuzzy logic methods in social sciences (1. ed.). Berlin, Germany: Springer. ISBN 9783642133428. Retrieved 31 October 2015.
- Davies, W. Martin (May 2006). "An 'infusion' approach to critical thinking: Moore on the critical thinking debate" (PDF). Higher Education Research & Development. 25 (2): 179–193. doi:10.1080/07294360600610420. Retrieved 2019-07-23.
- Desantis, Nick (23 January 2012). "Data Shows Bars With Most Noise Complaints, But Is It Just Sound and Fury?". The New York Times. Retrieved 31 October 2015.
- AJ Giannini. "Use of fiction in therapy". Psychiatric Times. 18(7): 56–57, 2001.
- The Black-or-White Fallacy entry in The Fallacy Files