On the term "Aristotelian Logic"

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I used to be a professional logician, which is to say the subject of my graduate studies was formal logic and computability. I would like to register my objection to the term "Aristotelian Logic" as is used in the context of this board.

Aristotle's logic was developed in a set of books consisting of Categories, On Interpretation, Prior and Posterior Analytics, Topics and Sophistical Refutations. Aristotle, himself, never referred to the subject matter of these books as "logic". Collectively these books constitute The Organon (or philosophical tool-kit).

The logic of inference developed by Aristotle was the logic of categorical syllogisms. This logic involves inference from premises of various form. The statement forms are: All A are B; No A is B; Some A is B, and Some A is not B. This are the only forms to which the categorical syllogistic logic applies.

In the discussions on this board, which is really being talking about is two valued logic. Logic in which propositions are either true or false. Logics of this sort might or might not be Aristotelian. For example, Intuistionistic Logic involves basic statements which are either true or false, but disjunctions do not obey the law of the exluded middle generally.

Since Aristotle, logic has undergone major expansion and development. Starting with Frege and Peirce in the 19th century, the logic of quantified propostions was developed. Boole invented a way of formalizing logic in a mathematical manner. This banner was taken up by Russell and Whitehead in their -Principia-. Afterward logic just went nuclear and has gone so far beyond what Aristotle discussed that old Mr. A. probably would not recognize his intellectual grandchildren and greatgrandchildren.

In any case Aristotlean Logic as Aristotle formulated it does not deal with the general logic of inference for conditional statements. It is this latter form that is most congruent with the logic mathematicians use in proving theorems. The best formalizations of the logic mathematicians use is Natural Deduction and the logic of Sequents (Gentzen, et al).

Here endeth my corrections to the misonomers commonly found on this board in referring to logic.

Ba'al Chatzaf

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Ba'al:

Home run. Thank you.

You are correct and it needed to be clearly stated. I did not have the knowledge in the field of modern "non-Aristotelian logic" to display it clearly as you did.

Aristotle was a great thinker. He has to be understood within his time and then you can be completely awed by how great he was.

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Aristotle was a great thinker. He has to be understood within his time and then you can be completely awed by how great he was.

Yes he was, much like Newton. As time goes on and we learn new things it does not mean that "old" knowledge is useless - it means that it's applicability is restricted. So Newton's physics has been restricted to relatively (to the speed of light) small velocities and weak (compared to black holes) gravitational fields. And of course it's not just Newton's physics but his name is associated with physics based on his work. Similarly with Aristotle, there are many endeavours based on his work (2-valued logic) and so the term Aristotelian logic means roughly based on this. Korzybski's view is that 2-valued logic is only applicable to mathematics and that the modern 00-value logic of probability is what we need to orient ourselves.

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There's a further complication in that Ancient Logic is not all from Aristotle. Some of it was developed by the Stoics.

Pre-Fregean logic encompasses further developments by various Scholastics, Leibniz, and others.

Robert Campbell

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Actually, on going back and checking, when Korzybski uses 'non-aristotelian' he doesn't refer solely to the logic of Aristotle, he refers mainly to the subject-predicate form of the propositions, especially the 'is of identity'.

The primitive form of representation which Aristotle inherited, together with its

structural implications and his 'philosophical grammar', which was called 'logic',

are strictly interconnected, so much so that one leads to the other.

In the present non-A system, I reject Aristotle's assumed structure, usually called

'metaphysics' (circa 350 B.C.), and accept modern science (1933) as my

'metaphysics'.

I reject the following structurally and semantically important aspects of the A-

system, which I shall call postulates, and which underlie the A-system-function:

1) The postulate of uniqueness of subject-predicate representation.

2) The two-valued elementalistic 'logic', as expressed in the law of 'excluded third'.

3) The necessary confusion through the lack of discrimination between the 'is'

of identity, which I reject completely, and the 'is' of predication, the 'is' of

existence, and the 'is' used as an auxiliary verb.

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There's a further complication in that Ancient Logic is not all from Aristotle. Some of it was developed by the Stoics.

Pre-Fregean logic encompasses further developments by various Scholastics, Leibniz, and others.

Robert Campbell

The Stoic Cryssipus developed logic based on the conditional which was a foreshadowing of Leibniz and Frege. Cryssipus was closer to the way mathematicians reason than was Aristotle.

Ba'al Chatzaf

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Bob K,

Chrysippus would be getting a lot more press if any of his books had been handed down to us intact.

The early Stoics weren't at all lucky in that department.

Robert C

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Bob K,

Chrysippus would be getting a lot more press if any of his books had been handed down to us intact.

The early Stoics weren't at all lucky in that department.

Robert C

Robert; Isn't the above true about many of the ancients.

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Actually, on going back and checking, when Korzybski uses 'non-aristotelian' he doesn't refer solely to the logic of Aristotle, he refers mainly to the subject-predicate form of the propositions, especially the 'is of identity'.

The primitive form of representation which Aristotle inherited, together with its

structural implications and his 'philosophical grammar', which was called 'logic',

are strictly interconnected, so much so that one leads to the other.

In the present non-A system, I reject Aristotle's assumed structure, usually called

'metaphysics' (circa 350 B.C.), and accept modern science (1933) as my

'metaphysics'.

I reject the following structurally and semantically important aspects of the A-

system, which I shall call postulates, and which underlie the A-system-function:

1) The postulate of uniqueness of subject-predicate representation.

2) The two-valued elementalistic 'logic', as expressed in the law of 'excluded third'.

3) The necessary confusion through the lack of discrimination between the 'is'

of identity, which I reject completely, and the 'is' of predication, the 'is' of

existence, and the 'is' used as an auxiliary verb.

This means the Count also rejects set theory. Given an set S there is a predicate s such that x in S if and only if s(x). Rejecting set theory means rejecting virtually all of mathematics. No predicates, no math.

Ba'al Chatzaf

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This means the Count also rejects set theory. Given an set S there is a predicate s such that x in S if and only if s(x). Rejecting set theory means rejecting virtually all of mathematics. No predicates, no math.

Ba'al Chatzaf

Yes, that's right, he rejects all of mathematics.

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This means the Count also rejects set theory. Given an set S there is a predicate s such that x in S if and only if s(x). Rejecting set theory means rejecting virtually all of mathematics. No predicates, no math.

Ba'al Chatzaf

Yes, that's right, he rejects all of mathematics.

Then he rejects the science of physics. Mathematics is not only the major tool of physics, but is absolutely indespensible for doing physics. Rejecting physics means rejecting all of the natural sciences including chemistry and biology, which gets me to what I asserted. The Count was a scientific ignoramus (as was Ayn Rand).

Ba'al Chatzaf

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Then he rejects the science of physics. Mathematics is not only the major tool of physics, but is absolutely indespensible for doing physics. Rejecting physics means rejecting all of the natural sciences including chemistry and biology, which gets me to what I asserted. The Count was a scientific ignoramus (as was Ayn Rand).

Ba'al Chatzaf

Yes, he was an ignoramus, what was I thinking? Thanks for pointing that out

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Then he rejects the science of physics. Mathematics is not only the major tool of physics, but is absolutely indespensible for doing physics. Rejecting physics means rejecting all of the natural sciences including chemistry and biology, which gets me to what I asserted. The Count was a scientific ignoramus (as was Ayn Rand).

Ba'al Chatzaf

Yes, he was an ignoramus, what was I thinking? Thanks for pointing that out

Don't misquote me. I said the Count was a scientific ignoramus, which is to say he was ignorant of science. That makes any assertions of his concerning human neurophysiology suspect. The Count was not alone. Virtually all of what was supposed concerning brain function (as opposed to gross brain anatomy) prior to 1950 was woefully lacking. We have learned more about how the brain works since 1950 than we thought we knew in the previous 3000 years.

Also there has been much progress in linguistics since the time the Count wrote on General Semantics. If I had to take anyone's word on language and how humans process it, I would soon believe what Stephen Pinker or William Calvin or Daniel Dennet has to say, than the Count.

Ba'al Chatzaf

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Don't misquote me. I said the Count was a scientific ignoramus, which is to say he was ignorant of science.

Oh sorry about misquoting you. But after you mentioned it, it became clear to me that he was in fact a complete ignoramus in all respects. Thanks again!

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Don't misquote me. I said the Count was a scientific ignoramus, which is to say he was ignorant of science.

Oh sorry about misquoting you. But after you mentioned it, it became clear to me that he was in fact a complete ignoramus in all respects. Thanks again!

G.S. and Ba'al:

I have never been at an internet conversion!

Was it a thrill?

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G.S. and Ba'al:

I have never been at an internet conversion!

Was it a thrill?

It was good for me, was is good for you?