It came up in discussion at the Formal Turn conference the other day, so I thought I’d preserve an old Twitter thread here: The first person to publish results on NAND and NOR (Sheffer stroke and Peirce arrow) was the Polish mathematician and Philosopher Edward Stamm (1886–1940). The publication was “Beitrag zur Algebra der Logik [Contribution to the algebra of logic]”, Monatshefte für Mathematik und Physik 22, 137–149 (1911). (Landon Elkind and I mention him in our paper on the genealogy of ‘∨‘.) Tomasz Grebski has a detailed information page on Stamm (in Polish, Google translation). He was a high school teacher, but received a degree from the University of Vienna, and was mainly interested in logic (algebra of logic, and also Peano — he published in Interlingua) and the history and philosophy of mathematics. Löwenheim reviewed the 1911 paper for the JFM but did not think the results “particularly useful.” (The list of reviews of Stamm’s work might serve as an approximation to a list of publications.) Stamm’s most well-known contribution is probably his study of Bradwardine’s Thorn manuscript in Isis. Roman Murawski has a section on Stamm in his book The Philosophy of Mathematics and Logic in the 1920s and 1930s in Poland. Stamm is also mentioned in Anna Brȯzek’s book on Twardowski as one of the many Polish philosophers who studied at the University of Vienna. Stamm used for NAND and ∗ for NOR. Since the | symbol has taken on the meaning of “or” anyway, I propose to henceforth refer to NAND as the “Stamm hook”