This site explores origins of phrases:
http://phrases.shu.ac.uk/meanings/14000.htmlQuoting: Meaning
A picture tells a story as well as a large amount of descriptive text.
Origin
The original quotation is 'One picture is worth ten thousand words', Frederick R. Barnard in Printer's Ink, 8 Dec 1921 retelling a Chinese proverb.
further discussions on that forum add:
it is said to be a Chinese proverb (whether made up by Kung Fu Tze, Confucius, or just a folk saying). But I have read that the original is better translated from Chinese in this way: "One showing is better than one hundred sayings." And I suppose a "showing" could be either a picture or diagram, on the one hand, or perhaps in in-person showing or demonstration. In any case, if we consider that, in English, a "saying" may typically involve ten words, then we can see where the "thousand words" bit was substituted for the direct translation.
PICTURE IS WORTH A THOUSAND WORDS, A -- One reference says “a picture is worth a thousand words” is “…a Chinese proverb long ago. The Russian writer Ivan Turgenev wrote (in ‘Fathers and Sons’ in 1862): ‘A picture shows me at a glance what it takes dozens of pages of a book to expound.’” From "The Dictionary of Cliches" by James Rogers (Ballantine Books, New York, 1985).
