2. Philosophy - Stefano Franchi

C OMBINATORIAL EXPLOSIONS
“solution” would it be? Of course, “solution” has to be used in scare quotes since it is no
longer the game theoretic concept provided by von Neumann. In fact, the definition of a
different concept of solution is precisely one of the first backward effects from chess to Ar-
tificial Intelligence, as we will see. That idea was born from a three-some composed of Her-
bert Simon, Allen Newell and Cliff Shaw, all of whom were working at RAND, either full-
time or as consultants, in 1950s. Let us begin by examining the first conceptual step by fol-
lowing the work of Claude Shannon.
In two short articles written in 1950, Claude Shannon entertains the possibility of a
thinking machine, and focuses his attention explicitly on a computer playing chess. If such
a machine existed, he suggested, its behavior would probably be considered “by some psy-
chologists” as a thinking process. It would first have to try out in the abstract various pos-
sible solutions to a given problem (e.g. a move in the chess game), in order to evaluate the
results of these trials and then to carry out the chosen solution. 29 The background of the ar-
ticle is in place: the construction of a chess-playing machine is being examined in order to
illuminate the possibility of a thinking machine in general, i.e. a machine able to exhibit
internal processes and structures essentially similar to human cognitive processes. I stress
this point because in order to appreciate what Shannon is about to say on the internal struc-
ture of the machine we should not forget that the implicit referent are the human cognitive
processes, and the structures and algorithm he presents are supposed to help either in a bet-
ter understanding of the human mind or in an actual reduplication of (parts of) it.
The basic problem can be split in three parts: (a) a translation system from chess posi-
tions to sequence of numbers must be chosen, (b) “a strategy must be found for choosing
the moves to be made” (2126), and (c) this strategy must be translated into “a sequence of
elementary computer orders, or a program” (ib.). The first and third problem are irrelevant
for what interests us here, concerned as they are with the problem of translating from hu-
man level to machine level. However, the problems (a) and (c) will prove very important
in later development of AI. (a) stands for the whole issue of knowledge representation, e.g.
the problem of how to translate the relevant information into an efficient set of data struc-
29. Claude Shannon, “A Chess-Playing Machine...,” 2132.
201