“Time flies like an arrow: fruit flies like a banana”

“Time flies like an arrow: fruit flies like a banana” is often credited to the comedian Groucho Marx (1890-1977), but Marx—if he ever said it—almost certainly has nothing to do with the saying. “Time flies” is from the ancient Latin saying tempus fugit. “Time flies like an arrow” (that is, time passes surely and swiftly) is a Chinese maxim that has been cited in English since at least 1815.
 
Anthony G. Oettinger, the Gordon McKay Professor of Applied Mathematics and Professor of Information Resources Policy (Emeritus) at Harvard University, and Susumu Kuno tested the saying “Time flies like an arrow” in 1963 into an IBM 7090 computer. The word “flies” can be both a noun and a verb. A November 1963 newspaper story reported that the computer would be tripped up on the sentence “Fruit flies like bananas.” “Time flies like an arrow; fruit flies like a banana” became popular in computational linguistics.
 
[This entry was aided by previous research on this term by the Quote Investigator.]
 
   
Wikipedia: Time flies like an arrow; fruit flies like a banana
“Time flies like an arrow; fruit flies like a banana,” is a saying, often interpreted humorously, that is used in linguistics as an example of a garden path sentence and syntactic ambiguity, and in word play as an example of punning, double entendre, and antanaclasis.
 
A fairly common variant is, “Time flies like the wind; fruit flies like a banana.” The semicolon is sometimes replaced by a full stop, or the second half may be preceded by the word but. Some versions have bananas instead of a banana.
 
Google Books
A Dictionary of the Chinese Language:
In Three Parts
Volume 1

By Robert Morrison
Macao: Printed at the Honorable East India Company’s Press
1815
Pg. 755:
But time flies like an arrow.
 
Google Books
Chinese Moral Maxims, with a free and verbal translation
Compiled by John Francis Davis
London: John Murray
1823
Pg. 28:
XXXVII.
Time flies like an arrow: days and months like a weaver’s shuttle.
 
14 November 1963, Boston (MA) Herald, pg. 2, col. 1:
MACHINE MAY LEARN ENGLISH—IN TIME
New Type of Fly Swats Computer
By FRED BRADY
Two Harvard professors sat in front of their best-behaved pupil—an IBM 7090 computer—and directed: “Parse this sentence: ‘Time flies like an arrow.’”
(...)
This time, not so pleased were Profs. Anthony Oettinger and Susumu Kuno.
(...)
The professors included this in their report yesterday in Las Vegas to a computer conference of the American Federation of Information Processing Societies.
 
Google News Archive
14 November 1963, Milwaukee (WI) Journal, “Those Foolish Computers,” pg. 28, cols. 1-2:
Take the simile “Time flies like an arrow.” A grammarian quickly identifies “time” as a subject of the verb “flies,” the verb being modified by the adverbial phrase “like an arrow.”
 
The computer will analyze the sentence in the same way but, being literal minded, it doesn’t stop here. It also will clack and bleep out beauties like these: “Determine the speed of flies as fast as you can” and “A species of fly, called time flies, enjoys an arrow.”
 
You could, of course, train the electronic brain to stop this foolishness and avoid misuse of “flies” in the simile. Then it would trip in handling a sentence like “Fruit flies like bananas.”
   
15 September 1964, Hattiesburg (MS) American, “Writers are safe” by Archy Fairly, pg. 2, col. 1:
With old automation creeping up on us in many ways we don’t even dream of, writers should feel relieved at the result of some recent computer tests at Harvard.
(...)
The thing seemed to do all right with some simple sentences, such as “people read English.” Another simple sentence, “time flys like an arrow,” made it stutter, display some pyrotechnics and say “er-uh” as many times as the man from Texas. The poor old machine just couldn’t figure out how fast flies fly, or whether a certain kind of flies, called time, are fond of arrows.
 
The programmers could make it answer one way or another, but then the machine couldn’t handle a simple sentence like: “Fruit flies like bananas.”
 
Google Books
The Computer Age and Its Potential for Management
By Gilbert Burck
New York, NY: Harper & Row
1965
Pg. 61:
This is still a long way off, but a program written (Pg. 62—ed.) by Anthony Oettinger and Susumu Kuno of Harvard’s Computational Library permits a computer to list all possible meanings. ‘Time flies like an arrow” might seem fairly straightforward to us, but a machine sees a number of other possibilities—for example, “Time the speed of flies as quickly as you can” (“time” being interpreted as a verb rather than a noun) and “Certain flies enjoy an arrow” (“time” being interpreted as an adjective, and “like” being interpreted as a verb). The machine could be instructed to rule out these particular offbeat parsings, but how would it handle the sentence, “Fruit flies like bananas”? Problems of semantics continue to plague investigators concerned with advanced man-machine communication.
   
The Harvard Crimson
Computer Use to Be Expanded Tenfold
By JOEL R. KRAMER,
Published: Tuesday, March 29, 1966
(...)
Take the sentence: “Time flies like an arrow.” Instead of having the machine say, “time: subject, verb, adjective,” and having the observer choose “subject” for this particular context, why can’t the machine be instructed to “figure it out?” “Time flies like an arrow” is not really very different from “Fruit flies like a banana,” but their diagrams are at opposite poles. In the latter, “fruit flies” are a species of fly and “like” is a verb. Why shouldn’t the machine say that “time flies” are another (admittedly rarer) species?
 
September 1966, Scientific American, “The Uses of Computers in Science” by Anthony Oettinger, pg. 168:
A grammar that pretends to describe English at all accurately must yield a structure for “Time flies like an arrow” in which “time” is the subject of the verb “flies” and “like an arrow” is an adverbial phrase modifying the verb. “Time” can also serve attributively, however, as in “time bomb,” and “flies” of course can serve as a noun. Together with “like” interpreted as a verb, this yields a structure that becomes obvious only if one thinks of a kind of flies called “time flies,” which happen to like an arrow, perhaps as a meal. Moreover, “time” as an imperative verb with “flies” as a noun also yields a structure that makes sense as an order to someone to take out his stopwatch and time flies with great dispatch, or like an arrow.
(...)
Worse yet anything ruling out the nonexisting species of time flies will also rule out the identical but legitimate structure of “Fruit flies like a banana.”
 
Google Books
Run, Computer, Run;
The Mythology of Educational Innovation

By Anthony G. Oettinger and Sema Marks
Cambridge, MA: Harvard University Press
1969
Pg. 29:
Worse yet, anything ruling out the nonexisting species of time flies will also rule out the identical but legitimate structure of “Fruit flies like a banana.”
 
Google Books
Handbook of Speech Pathology and Audiology
By Lee Edward Travis
New York, NY: Appleton-Century-Crofts
1971
Pg. 1165:
“Fruit flies like a banana.”
Semantics, the all too nebulous notion of what a sentence means, must be invoked to choose among the three structures syntax accepts for “Time flies like an arrow.” No techniques now known can deal effectively with semantic problems of this kind.