LFotW: False Dichotomy

This is a very important fallacy to recognize and is used quite often. This fallacy consists of arbitrarily reducing a set of many possibilities to only two. For example, evolution is not possible, therefore we must have been created (assumes these are the only two possibilities). Actually, this fallacy can apply to any premature reduction in the possible set of explanations for a phenomenon – not necessarily down to only two possibilities. UFO proponents, for example, will often analyze a sighting by saying the object was not a plane, not a balloon, and not celestial object, therefore it was a flying saucer. They are limiting the set of possibilities to a few easily dismissed choices, and the desired choice, while ignoring the many other possibilities.

This fallacy can also be used to oversimplify a continuum of variation to two black and white choices. For example, science and pseudoscience are not two discrete entities, but rather the methods and claims of all those who attempt to explain reality fall along a continuum from one extreme to the other.