Tuesday, April 11, 2017

Playing the "Occam's Razor" card - and getting it wrong

Occam's Razor is a principle for selecting between alternative hypotheses. The statement is:

If alternative hypotheses equally explain the facts then the simpler hypothesis is preferred.

This principle is used to claim that a simple explanation is correct when, in fact the explanation is not simple but is simplistic - naive and not actually covering the facts. Such uses of Occam's Razor pick a hypothesis and then cherry pick which facts to observe and which to dismiss. Famous examples, challenged by "fringe" archaeology, are common:

The "Clovis First" hypothesis: all humans arrived in America in a single "wave" of migration, after enough of the glacier had receded to make that possible. 
  - simple [CHECK]
 - all the facts [not unless you ignore thousands of examples of pre glacial sites, ignore the absence of Clovis material in Siberia, ignore the obvious diversity of arrowhead design styles] [NO CHECK]

The "No Europeans before Columbus" hypothesis.
 - simple [CHECK]
 - all the facts [not unless you ignore hundreds of European inscriptions, the tuberculosis resilience of New England's coastal tribes, as well as the general human tendency to go long distances in boats.] [NO CHECK]

The "Indians did not build in stone" hypothesis:
 - simple [CHECK]
 - all the facts [nope, there is not a single fact supporting this statement. Actually, the statement is not a testable hypothesis, and does not rise to the level of scientific statement] [NO CHECK]

So in practice Occam's Razor is used, not to choose between alternative hypotheses, but to exclude facts from consideration. If you hear Occam's Razor used in a conventional archeological discussion you can be almost certain it is being used to gloss over key details that do not fit the conventional thinking.


Tim MacSweeney said...

"If the scientific explanation is too hard to understand, make up a deceptively simple fable." - Rev. Nocents' Toothbrush (corollary of Occam's Razor)

Tim MacSweeney said...

July 3, 2013 — “The molecular biologist Sidney Brenner recently invented a delicious play on Occam's Razor, introducing the new term Occam's Broom…”