Accustomed to the veneer of noise, to the shibboleths of promotion, public relations, and market research, society is suspicious of those who value silence.
-- John Lahr,
The fish oil shibboleth is only the latest to be overturned in recent years. Vitamin supplements and fibre have also been found to provide no benefits.
-- Nigel Hawkes, "Nice idea, but where's the proof?", Times (London), March 24, 2006
Class size is another shibboleth: First, small class sizes do not increase learning, and, second, class sizes have become quite small anyway.
-- Jay Nordlinger, "The Anti-Excusers", National Review, October 27, 2003
Shibboleth is from Hebrew shibboleth, "stream, flood," from the use of this word in the Bible (Judges 12:4-6) as a test to distinguish Gileadites from Ephraimites, who could not say 'sh' but only 's' as in 'sibboleth'.