False dichotomy

A false dilemma (also called false dichotomy, false binary, black-and-white thinking, bifurcation, denying a conjunct, the either–or fallacy, fallacy of exhaustive hypotheses, fallacy of the excluded middle, the fallacy of false choice, or the fallacy of the false alternative) is a type of informal fallacy in which something is falsely claimed to be an either-or situation, when in fact there is at least one additional option. The opposite of this fallacy is argument to moderation.

The options may be a position that is between two extremes (such as when there are shades of grey) or may be completely different alternatives. Phrasing that implies two options (dilemma, dichotomy, black-and-white) may be replaced with other number-based nouns, such as a "false trilemma" ("false trichotomy," etc.) if something is reduced to only three options.

A false dilemma can arise intentionally, when a fallacy is used in an attempt to force a choice or outcome.

The false dilemma fallacy also can arise simply by accidental omission of additional options rather than by deliberate deception. For example "Stacey spoke out against capitalism, therefore she must be a communist" (she may be neither). "Roger opposed an atheist argument against Christianity, but he would say that, he's 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. Conversely some believe free will is the ability to choose from beyond apparent 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 of each other, 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.

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