What is the name for the inverse of an aphorism

Solution 1:

An inversion such as "a word is worth a thousand pictures" is described as an implied chiasmus by Wordsmith.org founder, Anu Garg, here, quoting these immortal words of Kermit the Frog:

Time's fun when you're having flies.

A chiasmus is "a rhetorical inversion of the second of two parallel structures." In the link, which is well worth reading, the examples of the inversion are of the sort: "Ask not what your country can do for you; ask what you can do for your country." So the implied chiasmus would be simply the second part, where the first (unspoken) one is the better known aphorism ("time flies when you're having fun" or "a picture is worth a thousand words").

Solution 2:

If

Screaming: Words speak louder than actions ("Actions speak louder than words")

is a structure that imitates OP's example of "A word is worth a thousand pictures", then it is a

Transpositional pun (Wikipedia)

a complicated pun format with two aspects. It involves transposing the words in a well-known phrase or saying to get a daffynition-like clever redefinition of a well-known word unrelated to the original phrase. The redefinition is thus the first aspect, the transposition the second aspect.

"A hard man is good to find." - Mae West
"No Left Turn Unstoned"

TP on UNCF's motto, "A Mind is a Terrible Thing to Waste."

_{(source: wasteisaterriblethingtomind.com)}

^{http://wasteisaterriblethingtomind.com/}