Sweeping Generalization

Fallacy of accident, dicto simpliciter, destroying the exception, dicto simpliciter ad dictum secundum quid

A sweeping is a deductive fallacy committed in an argument based on generalization (statistical syllogisms) in which an exception to the generalization is ignored.

As applied to intelligent [sick] design theory this fallacious argument runs “we observe the products of (human) intelligence, so complex functionality implies intelligent design – biological life is complex and functional – therefore life must have been created by an intelligent designer.” This is the ‘intelligent [sick] design theory’ reworking of Paley's "Blind Watchmaker" argument (1802) argument.

The illogical difficulty with this argument lies in the fallacious generalization from our observation that human intelligence creates complex and functional objects (watches, computers, airplanes) to the unfounded conclusion that something that ‘accidentally’ shares only the features of functionality and complexity – biological life – must have arisen by the same mechanism, namely application of intelligence. This fallacious argument could also be regarded as a false analogy. In general, analogies are useful for the purposes of explanation, but they are risky endeavors in arguments. The ‘intelligent [sick] design theory’ platform, due to its lack of factual or experimental basis, consists almost entirely of analogies. That is ‘intelligent [sick] design theory’ is 'clearly religious and indubitably not science'.

A clear example of this fallacy: "We observe that tomatoes grow on plants, so the existence of round red fruit implies tomato plants – an apple is a round red fruit – therefore an apple must be the product of a tomato plant." True premises have been over-extrapolated to an incorrect conclusion.

If the complex object in question shares more relevant features with the observed object, then the conclusion may be true. “We observe that electronic devices are the products of human intelligence, so the existence of an electronic device implies human intelligent design – a television is an electronic device – therefore a television must be the product of human intelligence.”

Quo Vadis?
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