Thread:Ralf Hat/@comment-27621300-20160206180832/@comment-24491361-20160207213829

The words gullible and credulous are commonly used as synonyms. Goepp & Kay (1984) state that while both words mean "unduly trusting or confiding", gullibility stresses being duped or made a fool of, suggesting a lack of intelligence, whereas credulity stresses uncritically forming beliefs, suggesting a lack of skepticism.[3]  Jewell (2006) states the difference is a matter of degree: the gullible are "the easiest to deceive", while the credulous are "a little too quick to believe something, but they usually aren't stupid enough to act on it."[4]

Yamagishi, Kikuchi & Kosugi (1999) characterize a gullible person as one who is both credulous and naïve.[5]  Greenspan (2009) stresses the distinction that gullibility involves anaction in addition to a belief, and there is a cause-effect relationship between the two states: "gullible outcomes typically come about through the exploitation of a victim's credulity."[6]

Etymology and History
A popular test of gullibility is to tell a friend that the word gullible isn't in "the" dictionary; a gullible person might respond "Really?" and go to look it up. Unsurprisingly, modernEnglish language dictionaries do indeed contain the word, although some of the earliest dictionaries did not.

The verb to gull and the noun cullibility (with a C) date back to Shakespeare and Swift, whereas gullibility is a relatively recent addition to the lexicon. It was considered aneologism as recently as the early 19th century.[7] [8]  The first attestation of gullibility known to the Oxford English Dictionary appears in 1793, and gullible in 1825. The OED givesgullible as a back-formation from gullibility, which is itself an alteration of cullibility.[9]

Early editions of Samuel Johnson's A Dictionary of the English Language, including those published in 1797 and 1804, do not contain "gullibility" or "gullible".[10]  An 1818 edition byHenry John Todd denounces "gullibility" as "a low expression, sometimes used for cullibility".[7]  Gullibility does not appear in Noah Webster's 1817 A dictionary of the English language,[11]  but it does appear in the 1830 edition of his American dictionary of the English language, where it is defined: "n. Credulity. (A low word)".[12]  Both gullibility andgullible appear in the 1900 New English Dictionary.<sup class="reference" id="cite_ref-OEDonline_9-1" style="line-height:1;unicode-bidi:isolate;font-size:11.2px;">[9]