2. Philosophy - Stefano Franchi

T HE SUPPLEMENT
Furthermore, let suppose that C represents the game of chess in its more general sense.
C
The game of chess as it is really played, e.g.
"in itself"
The claim of self-containment can be interpreted as a double requirement on the rela-
tionships among A, B, and C. First, it is clear that no situation like the following can arise:
A
B
A and ~B B and ~A
B and A
Irreproducible Iegal
chess positions
Illegal rule-produced
chess positions
There cannot be configurations that the rules cannot generate nor there can be rule-
generated configurations that do not count as legal positions. 2 If we consider only the rules
governing the movement of the pieces, the coincidence between A and B seems, nowadays
at least, fairly trivial to accomplish, because it just means that the machine must be able to
play a “legal” game of chess. 3 However, we have seen that it is crucial to Artificial Intelli-
gence that “heuristic” rules be included as well in its repertoire, e.g. rules that govern the
2. Completeness and consistency, roughly speaking, must endow the relationship between A and B.
3. The task was far from trivial, instead, when computing machines were primarily considered number
crunchers and the basic tools needed to represent chess-positions and transitions between them did not
exist yet. In fact, the early literature on chess-playing machine quotes this as a major accomplishment.In
the early stages of development of computer science, the expressive needs of Artificial Intelligence
programs represented a major stimulus toward the development of higher-level programming
languages, like IPL, the predecessor of LISP (later developed by John mcCarthy) that Simon, Shaw and
Newell, had to invent in order to pursue symbolic programming and, of course, LISP itself. See Allen
Newell, J.C. Shaw, and Herbert Simon, “Chess-Playing Programs and the Problem…,” 63 ff, and
above, sect. IV.3 for a detailed discussion of this issue.
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