A rare notebook of Alan Turing’s which dates back to his work breaking the Enigma code is expected to sell at auction for at least £1m.
The 56-page manuscript sees the codebreaker working on the “foundations of mathematical notation and computer science”, said Bonhams, which will auction the notebook in New York on 13 April. It dates from Turing’s days in Bletchley Park in 1942, and according to Bonhams’ specialist Cassandra Hatton, “its mathematical content gives an extraordinary insight into the working mind of one of the greatest luminaries of the 20th century”.
“The Leibniz notation I find extremely difficult to understand in spite of it having been the one I understood the best once!” writes Turing, at one point, in a notebook bought in a Cambridge stationer’s. “It certainly implies that some relation between x and y has been laid down eg, y=x2+3x …”