A note from the past

I'll bet that none of the list members is aware of this part of Dave's
earlier life.
Jack Haas

"David F. Siemens, Jr., writer-producer for Moody Institute of Science
was recently informed that his paper, "An Extension of Fitch's Rules"
has been accepted for publication in Volume 7 (about December, 1961)
of /Zeitschrift fur Mathematische Logik und Grundlagen der Mathematik/.

The background for this paper goes back to Whitehaad and Russell's,
/Principia Mathomatica/. In the fundamental logical calculus) they used
two primitive symbols which they then used in defining the other logical
connectives. With these, and letters to stand for entire sentences or
propositions) they presented a set of axioms and a set of rules of
transformation. This was the logical calculus. Nicod later reduced the
whole of their basic logic to one axiom and one rule of transformation.
Still later an American logician, Fitch, developed a logical calculus
which had no axioms, only a set of rules of transformation for each of
the PM logical connectives, but no one seems to have published such
rules for Nicod's Shaffer stroke. Siemens' study presents a set of
rules, analogous to Fitch's, for the Sheffer stroke and, on the basis of
these rules, presents a demonstration of Nicod's axiom (that it is a
tautology) and of Nicod's rule.

Well, as I always said, "Ask a crazy question and you got a crazy
answer" (F. Alton Everest, ASA News Letter, Oct. 1961)
Received on Wed Jan 25 17:32:50 2006