Completion of the Formulario

Abstract

On 31 March, 1906, Peano sent an article to the Circolo Matematico of Palermo that was reported at the 8 April session and printed in the Rendiconti [133]. It shows that he had not lost interest in questions pertaining to the foundations of mathematics and, on the contrary, had some penetrating things to say. It is true that he had been somewhat reticent. He never commented in print on Burali-Forti’s discovery of an antinomy in Cantor’s set theory in 1897 and Bertrand Russell, after discovering his paradox a year earlier, complained is his 16 June, 1902, letter to Frege: “I have written to Peano about this, but he still owes me a letter.” Peano did, however, comment on some of the ideas of this article in a letter to Russell of 16 February, 1906.