# RE: Sorting out

Bill Hamilton (hamilton@predator.cs.gmr.com)
Wed, 10 Apr 1996 08:22:07 -0400

Dennis Sweitzer quoted Paul:
>
>>>>>> The recent discussions on historicity, dualism and so forth, mostly
>seem
>to revolve around the nature of truth. I haven't had time to study all the
>details of the discussions, but I'm trying to sort all this out. I propose
>an equation:
>
> T = M + O + U
>
>or
>
> truth = meaning + objectivity + unity.
><<<<<<<<<<<<<<<<
>
>But may have meant something else. Popular culture tend to use '+' as
>'and', but standard computer conventions let FALSE=0, and TRUE=1 (or >1).
> Consequently, M+O+U implies that as long as one of M, or O, or U is true,
>then T is true.
>
>Alternatively,
>
> T= M * O * U
>
>So that T>0 only if M, O, and U are not equal 0. So the '+' operation
>corresponds to (inclusive) 'logical or', and the '*' operation corresponds
>to logical 'and'.
>
[remainder of Dennis' interesting discussion snipped]

>If nothing else, I have convinced myself that I don't know what Paul meant,
>although I thought I knew when I first read his message.
>
>Grace & peace .....Grace | Peace???? ...... MAX (Grace, Peace)???? .....
>
A number of years ago -- more than I care to remember -- a high school
advanced math course touched on symbolic logic. The teacher showed us how
to formulate and analyze propositions, and I gave him a great deal of
trouble, because I insisted on trying to formulate nonmathematical
propositions in symbolic logic. Then when a "common sense" analysis of my
propositions didn't yield the same result as the logic, I complained that
symbolic logic didn't work. The problem of course was not symbolic logic,
but my efforts to formulate problems that are difficult to describe in set
theory. A few years ago a number of computer science researchers were
working on proofs of correctness for computer programs. Programs can in
principle be expressed as logical propositions, so in principle their
correctness can be proved. I'm not an expert in this field, but my
understanding is that in order to establish correctness, programs had to be
written according to a set of restrictive rules that eliminated some useful
programming methods. But what was even more restrictive was that many
kinds of useful interaction with the world outside the computer could not
be handled in such proofs. My point is that in order to use mathematical
logic to handle real-world truths, you have to convert the real-world
truths into logical propositions. In order to arrive at statements that can
be analyzed, you are likely to lose a great deal of the richness of the
knowledge you're dealing with in the translation. If there are computer
programs that defy logical analysis, imagine the difficulty of analyzing
ancient documents. I'm not saying that nothing can be gained by analyzing
ancient documents. Clearly a great deal _has_ been gained. But analytical
methods have their limitations.

The article by Willimon in Christianity Today a while ago makes some good
points about truth. The chief one is that for Christians, truth is
intimately connected to the Person of Jesus Christ.

Bill Hamilton | Chassis & Vehicle Systems
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