Just-so story

A just-so story, also called the "ad hoc" fallacy, is a term used in academic anthropology, biological sciences, and social sciences. It describes an unverifiable and unfalsifiable narrative explanation for a cultural practice or a biological trait or behavior of humans or other animals. The use of the term is an implicit criticism that reminds the hearer of the essentially fictional and unprovable nature of such an explanation. Such tales are common in folklore and mythology (where they are known as "etiological myths" — see etiology).

Rudyard Kipling's Just So Stories

This phrase was popularized by the publication in 1902 of Rudyard Kipling's "Just So Stories", containing fictional and deliberately fanciful tales for children, in which the stories pretend to explain animal characteristics, such as the origin of the spots on the leopard. [ [http://www.4literature.net/Rudyard_Kipling/How_the_Leopard_got_his_Spots/ Rudyard Kipling, How the Leopard got his Spots] in JUST SO STORIES FOR LITTLE CHILDREN, 1902]

Evolutionary Biology

Darwin's Whale story

Some of Charles Darwin's origin accounts have been compared to Kipling's Just-So Stories.Fact|date=August 2008 For example, in the first edition of On the Origin of Species, Darwin gave an example of how a bear might transform into a whale sized creature.

In North America the black bear was seen by Hearne swimming for hours with widely open mouth, thus catching, like a whale, insects in the water. Even in so extreme a case as this, if the supply of insects were constant, and if better adapted competitors did not already exist in the country, I can see no difficulty in a race of bears being rendered, by natural selection, more and more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale. [Darwin, Charles, On The Origin of Species, 1859, London, John Murray, 1st Edition, CHAP.VI, 184 DIFFICULTIES ON THEORY.] [ [http://pages.britishlibrary.net/charles.darwin/texts/origin1859/origin06.html Origin of Species] 1st Edition, Chapter VI, pg.84] Dead link|date=March 2008

Darwin deleted this from later editions. Modern cladistics places the whale as being most closely related to the hippopotamus.

Lamarckian Just-so stories

Because of some Just-so stories' extravagant nature, which parody the Lamarckian theory of heredity (that traits acquired physically in life may be inherited by subsequent generations), the phrase "just so story" has acquired the meaning, in evolutionary biology, of an unnecessarily elaborate and speculative evolutionary explanation, which may fit available the facts but lacks any empirical support. For example, Sigmund Freud's evolutionary theory of psychopathology has been described as being "not credible" because "It is based on just-so stories and a thoroughly discredited evolutionary mechanism, Lamarckian use-inheritance." [ [http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=411517 Remembering the Evolutionary Freud] Allan Young; Science in Context; (2006) 19: 175-189 Cambridge University Press]

Evolutionary biology critiques

Scientific reviews refer to Just-so stories for narratives failing scientific rigor. e.g.,

Wade’s explanations commit various well-known errors, such as equating correlation with causation and extrapolating from individual traits to group characteristics….The book has many internal inconsistencies, and one can easily find contrary evidence or readily construct alternative ‘just so’ stories that invoke the same genetic scenario and the same kind of reasoning. [ Weiss, Kenneth M. & Buchanan Anne V.; In your own image Nature 441, 813-814 (15 Jun 2006)]

Evolutionary psychology

Many of the claims of evolutionary psychology that certain human traits were naturally selected for because of the environment humans lived in thousands of years ago are criticized as modern just-so stories. e.g.,

Flanagan does give a just-so story about how consciousness could have evolved through natural selection, but just-so stories run counter to his very simple methodological suggestion --- use all the information one can get from any science that seems relevant to the task at hand; otherwise, wait until the data is available. Just-so stories aren't very scientific. Indeed, as long as we are allowed to spin arm-chair theories, why not consider consciousness to be a phenotypic free-rider, like the chin, such that no Darwinian story is going to explain its purpose, since it does not have one. [Hardcastle, Valerie Gray and Pruim, Peter E. 1993, PSYCHE, 1(2), December 1993]

Criticism and misuse of the term "Just So Story"

Many hypotheses that have been labeled by critics as "just so stories" are in fact empirical questions, and are potentially falsifiable. Or, the hypotheses are sufficiently plausible that they are taken seriously by experts in the field.

For example, in cosmology, string theory as yet has no empirical evidence to support it. Yet it is seen by many cosmologists as mathematically plausible, and it may be empirically falsifiable in the future given new research tools.

Critics of evolutionary psychology have sometimes used the term "just so story" as a derogatory way of describing alternative hypotheses which need empirical evaluation, but which are plausible and are taken seriously by knowledgeable experts.
Leda Cosmides noted in an [http://www.psych.ucsb.edu/research/cep/ledainterview.htm interview] :

Those who have a professional knowledge of evolutionary biology know that it is not possible to cook up after the fact explanations of just any trait. There are important constraints on evolutionary explanation. More to the point, every decent evolutionary explanation has testable predictions about the design of the trait. For example, the hypothesis that pregnancy sickness is a byproduct of prenatal hormones predicts different patterns of food aversions than the hypothesis that it is an adaptation that evolved to protect the fetus from pathogens and plant toxins in food at the point in embryogenesis when the fetus is most vulnerable – during the first trimester. Evolutionary hypotheses – whether generated to discover a new trait or to explain one that is already known – carry predictions about the nature of that trait. The alternative – having no hypothesis about adaptive function – carries no predictions whatsoever. So which is the more constrained and sober scientific approach?

Further, some hypotheses that have been labeled as "just so stories" by misinformed critics do indeed have some empirical support. See [http://itb.biologie.hu-berlin.de/~hagen/papers/Controversies.pdf Controversies surrounding evolutionary psychology] by Edward H. Hagen, and books by Segerstråle (2000) [Segerstrale, Ullica (2000). "Defenders of the Truth: The Battle for Science in the Sociobiology Debate and Beyond". Oxford: Oxford University Press.] and Alcock (2001) [Alcock, John (2001). "The Triumph of Sociobiology". Oxford: Oxford University Press.] .

The generation of plausible hypotheses is one part of theory creation and evaluation in normal science.

Notes and references

ee also

* Just So Stories
* Rudyard Kipling
* Evolutionary biology
* Evolutionary psychology
* Is-ought problem
* Pourquoi story
* Texas sharpshooter fallacy