Re: Codd and many-valued logics

On Monday, May 30, 2016 at 6:48:00 AM UTC-7, Nicola wrote:
> It seems to me that Codd never referenced the literature on many-valued
> logics in his papers (I'd be glad to be proven wrong). Do you have any
> idea why?

In his Version 2 book REFERENCES intro:

    Several texts dealing with predicate logic also appear in the reference list. In descending order of difficulty, they are as follows: (Church 1958), (Suppes 1967), (Exner and Rosskopf 1959), (Stoll 1961), and (Pospesel 1976).

The texts appear in the references list that follows. They are referenced in the text. But only in a general way. From the section Power of the Relational Language:

    Excluding consideration of general logical inference, RL as a language has the full power of four-valued, first-order predicate logic [Pospesel 1976, Stoll 1961, Suppes 1967, Church 1958].

(Although this is odd because without logical inference it's a bit much to claim that one has a logic let alone the "full power" of one with it.

I don't know Codd's reasons for the nature of his references to logic.

But the little of logic that he used hardly needs references.

Ie a few truth tables. Eg for AND, OR, NOT & IS NULL in 3VL.

There isn't much else that's "logical" about his use of MVLs. I don't know what you would expect to find of use in a reference.

philip Received on Sun Jun 05 2016 - 04:44:56 CEST