Trifurcation

A false dilemma 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.

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

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 capitalism, therefore she must be a communist" (she may be neither). "Roger opposed an atheist 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 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.

Common phrases expressing similar or synonymous concepts include:

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, the city would drastically change in a negative way. 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 the bar could simply lower its noise levels, or install soundproofing structural elements to keep the noise from excessively transmitting onto others' properties.

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