Argument from poor design

The argument from poor design, also known as the dysteleological argument, is an argument against the existence of a creator God, based on the reasoning that an omnipotent and omnibenevolent God would not create organisms with the perceived suboptimal designs that can be seen in nature.

The argument is structured as a basic modus tollens: if "creation" contains many defects, then design is not a plausible theory for the origin of our existence. It is most commonly used in a weaker way, however: not with the aim of disproving the existence of God, but rather as a reductio ad absurdum of the well-known argument from design, which argues that living things are too well-designed to have originated by chance, so must have been deliberately created by an intelligent God.

Although the phrase "argument from poor design" has seen little use, this type of argument has been advanced many times using words and phrases such as "poor design", "suboptimal design", "unintelligent design" or "dysteology/dysteological". The last of these is a term applied by the nineteenth-century biologist Ernst Haeckel to the implications of organs so rudimentary as to be useless to the life of an organism. Haeckel, in his book The History of Creation, devoted most of a chapter to the argument, ending with the proposition (perhaps with tongue slightly in cheek) of "a theory of the unsuitability of parts in organisms, as a counter-hypothesis to the old popular doctrine of the suitability of parts". The term "incompetent design", a play on "intelligent design", has been coined by Donald Wise of the University of Massachusetts Amherst to describe aspects of nature that are currently flawed in design.

Traditional theological responses generally posit that God's creation was perfect but that humanity's misuse of its free will to rebel against God has resulted in the corruption of good design.

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