At any rate, what it comes down to is that my life for the next several years will consist of flying back and forth between Hanover and Berlin (with perhaps the occasional excursion to St. Petersburg!) trying to work out a beautiful set of logical rules. That matches well with the other part of the arithmetickal engine project, namely, writing down the set of rules that will govern how it processes symbols. As a matter of fact I should like to think that these two sets of rules—the one governing monads, the other governing the mechanical mind—will turn out to be one and the same. So I propose to take on this part of the undertaking myself, as it is so similar to what I am doing anyway.