Monday, March 17, 2014

On the Logic of Propositions and the Magisterium of Philosophy

A proposition is a statement that says something about reality, and what it claims or represents can be either true or false. There are four kinds of propositions, and the fourth can be divided into separate categories but it is essentially a statement of one order.

The four kinds of proposition are:

1) Analytic: "All triangles have three sides."

2) Internal: "I have a headache."

3) External, or Empirical:  "I see a table here before me."

4) Categorical: which can be expressed as a moral proposition,  "Human beings should not kill other human beings"; as a political proposition, "The Crimean vote to succeed from Ukraine is illegal according to international law"; or as an aesthetic proposition, "Fellini's films are beautiful even when they are grotesque."

As far as my understanding takes me, there is only one type of proposition that can be proven true or false; that is, the Analytic proposition. The others are rather statements of a different order. Internal propositions do not describe anything that can be logically proven: moreover, whether they are true or false has no bearing upon our philosophical understanding or the description of actual reality. Rather such statements guide (or do not guide) our behavior. External propositions can be no more than descriptive. They are not logically true, but rather they are descriptive; that is, they are useful. If descriptive statements are false then they are simply nonsense; they don't inform us about anything, except perhaps that a person who vocalizes them is careless, is ignorant, is misinformed, is a joker, or is a liar. Categorical propositions--or rather expressions of moral, political, or aesthetic belief--are neither true nor false, they are simply statements about belief. The question is, are they persuasive?

The key point I am turning upon here is what can be proven with logic.  The philosophical material that informs the various subjects addressed by philosophers (or by social-scientists, scientists, and poets) is itself very thin.  That is, their theories, hypotheses and mythological constructions are enchanting, intriguing, or somehow appealing to our understanding; nevertheless, they remain matters that cannot be proven with logic, and so we must remain circumspect about the truth claims of the many voices that seek to sway our opinions, or which seek to enlist us in their projects.  As for science, that can still proceed, for our science really does not seek what is true, but merely what seems to work at any given point in time, or in some context, or when given a certain set of circumstances or conditions. Nor do I want a science that seeks to do more.

5 comments:

Horace Jeffery Hodges said...

"If descriptive statements are false then they are simply nonsense; they don't inform us about anything, except perhaps that a person who vocalizes them is careless, is ignorant, is misinformed, is a joker, or is a liar."

A liar is one who knows what is true and what is false but expresses what is false as if true. Your own statement seems to presuppose what you have denied, namely -- if I might paraphrase -- that descriptive statements cannot be true or false, merely useful or not useful (which, by the way, actually reminds me of the pragmatic definition of truth).

Why not simply explain what is meant by "truth" in analytic propositions, internal propositions, external propositions, and categorical propositions. I don't see why the "logical" definition of truth should be binding outside of logic.

Jeffery Hodges

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Carter Kaplan said...

"... descriptive statements cannot be true or false, merely useful or not useful..."

Well, short answer: They cannot be PROVEN true or false. That is, logic cannot prove them true or false.

Reference Wittgenstein's famous argument with Russell: "You cannot use logic to prove that there is no rhinoceros in the room." Russell looks under the table, laughs, and so on... but in the end admits W is right. That is, logic cannot prove one way or another whether or not there is a rhinoceros in the room. In the same way, logic cannot prove internal, external, moral or aesthetic propositions. Such propositions fall outside of legitimate philosophical inquiry; that is, philosophy's task is to show that these are not philosophical questions.

Horace Jeffery Hodges said...

Well, if we want to be really strict, logic can't prove anything either without our agreement on premises.

And there's always Gödel's incompleteness theorem to deal with . . .

Jeffery Hodges

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Carter Kaplan said...

"Well, if we want to be really strict, logic can't prove anything either without our agreement on premises."

Of course we can speculate about such matters, but when it comes down to some of the political ramifications of the "claims" of moral and political philosophers--technocracy, totalitarianism, social engineering, corporate global government, and so on--well, yeah, let's be "strict," by all means.

Carter Kaplan said...

Interesting article here:

"Modern Moral Philosophy" by G. E. M. Anscombe