WFF 'N PROOF: The Game of Modern Logic

This set of 21 games taught principles of modern logic. Players learned to combine grammatically correct logical statements called well-formed formulae (WFFs) into logical proofs. WFF 'N Proof was developed by Layman E. Allan of Yale University Law School under a grant from the Carnegie Corporation for ALL (Accelerated Learning of Logic). Allen applied for a trademark for WFF ‘N Proof in August 1961; it was registered the following year but has now expired. The game sold from 1962.
The set includes 18 wooden cubes with small letters, representing sentences, and 18 with large letters, representing logical rules of inference. The simplest of the games in WFF ‘N Proof were designed to teach young children how to arrange these cubes on a series of paper mats to form WFFs. The remaining games were meant to teach how to argue logically. These games involve assuming the truth of WFFs of certain forms and concluding the truth of WFFs of other forms using logical rules of inference. Thus players proved theorems but did not use that terminology. The most advanced of these games were designed to challenge college students.
The set also includes a timer, a book of instructions written by Allen, WFF ‘N Proof: The Game of Modern Logic (New Haven: Autotelic Instructional Materials Publishers, 1970), and a leaflet describing "Games for Thinkers" from WFF 'N PROOF Publishers of Turtle Creek, Pennsylvania. All these materials are stored in a plastic case that is marked on the cover: WFF'N PROOF (/) The Game of Modern Logic.
In 1968 Layman Allen moved from Yale to the University of Michigan with a joint appointment in the Law School and the Mental Health Research Institute, where he continued his work on instructional games. Over the years the name and location of the distributor of WFF ‘N Proof changed, although the phrase “Games for Thinkers” has been associated with it from before Allen’s move to Ann Arbor. Price lists in the WFF ‘N PROOF Newsletters (part of the documentation in accession 317891) indicate that at first the game was distributed by WFF ‘N PROOF in New Haven, Connecticut, and sold for $6.00. In 1970 the price was raised to $8.00 and in 1971 the game was distributed by WFF ‘N PROOF through Maple Packers in Turtle Creek, Pennsylvania. At some point a firm called Learning Game Associates of Ann Arbor took over distribution of the game and donated this example to the Smithsonian in 1975. Later the Accelerated Learning Foundation of Fairfield, Iowa, became the distributor.
Reference: Games For Thinkers Website.
Currently not on view
date made
ca 1970
Allen, Layman E.
Learning Games Associates
Place Made
United States: Michigan, Ann Arbor
Physical Description
plastic (overall material)
paper (overall material)
wood (overall material)
overall: 4 cm x 14.5 cm x 21.5 cm; 1 9/16 in x 5 11/16 in x 8 7/16 in
ID Number
accession number
catalog number
Credit Line
Gift of Learning Games Associates
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Data Source
National Museum of American History, Kenneth E. Behring Center


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