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# Necessary And Contingent Truths

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If you distinguish between being a tautology and being true by dint of its meaning, I don't see how.
The distinction I'm drawing is between constructing formal tautologies and contradictions of the type "A&^A" or "A|^A", versus the yet unexplained notion of sentences that are true because of their meaning. I understand the nature of formal tautologies, for example "All circles are circles", "No circles are not circles". The distinction is that I know what an "A&^A" truth is, but I still don't know what is meant by "true because of meaning". As far as I know, such sentences cannot be reduced to formal contradiction, but I'm not sure, since I don't know what sentences are considered to be true because of meaning as opposed to fact.
I'm also confused by how my use of 'circle' is non-technical, considering that this is the standard definition in geometry.
No, I said that your definition is fine in technical usage, but it is wrong in ordinary usage. That means that sentences about circles may be considered necessarily true or contingently true depending on context of usage.
In any case, you agree that there is a distinction between categories of statements--namely, between the tautological (i.e. necessarily true) and the contingent, and that is all that I was pointing out. Nobody has ever claimed, to my knowledge, that the necessarily true statements are informative or "affect the meaning of the terms" (whatever that means).
I don't agree that there are contingently true statements, also I don't equate the tautological with the necessarily true. A tautological sentence is one that mechanically translates into a provable formal proposition (of the form "A|^A") using symbol substitution plus some well-studied rules of natural language semantics (which can turn "All dogs are dogs" into "Ax(D(x)->(D(x))"). You can't do that with the sentence "All circles are not squares", so I would need to see your argument that the sentence is always true.
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The only clear difference that I know of is that in one case the standard definitions of two concepts are mutually exclusive.
Well yeah, exactly Thats pretty much all that's needed for some form of the 'true by fact' and 'true by meaning' distinction to get a foothold. It is theoretically hypothetically arbitrarily possible that we could find a superbaby that can actually read Atlas Shrugged, but we it is literally impossible for us to find a square triangle. Our concept of 'triangle' rules out the possibility of it having 4 sides, while our concept of 'baby' doesnt rule out the possibility of a baby being able to read Atlas Shrugged.

Anyhow, what I want to know is what the meaning of "dog" is. Without knowing that, I don't see how I can decide whether the truth of "dogs are mammals", "dogs are quadrupeds" or "dogs can breed with jackals" is true simply from the meaning of the concepts.

Well in one sense, you can say that the meaning of the concept 'dog' is actual real dogs. But this isnt the meaning of meaning which is meant here. Saying that 'dog' means dogs is true, but it doesnt really get us anywhere here because it doesnt identify the criteria we actually use for deciding that a certain entity is a 'dog'.

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Is there any proof of why human action is different than non-human action however?
Are you asking, how do we know that humans have free will? There's a fair amount of talk about that here, here. If you are asking what is the physical nature of free will, I don't know (I'm not the only one who doesn't know). Still, I know that it's a fact, and a self-evident one. Also, there is a bit more to volition than non-determinism. A random machine is not volitional; what you need to be volitional is the ability to chose.
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Well in one sense, you can say that the meaning of the concept 'dog' is actual real dogs. But this isnt the meaning of meaning which is meant here.
So what do you mean by "mean"? If you give a formal definition of X and Y, you might be able to produce propositions including X and Y which are deductively provable tautologies. That is not how the analytic-synthetic dichotomy was seen (though Katz & Fodor certainly had high hopes for solving the "problem" in this way, back in the day).

I'm not sure whether the concept "baby" precludes a future baby reading AS. It might be necessary to form a new concept if that came to pass. That's a difference from sentences about 6-month olds.

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Ditto Hal.

The sentence, "All bachelors are unmarried males," is true by dint of what the sentence means to communicate. That is to say, simply by the meaning of 'bachelor', 'unmarried', 'male', and the standard English grammar, this is necessarily a true statement. I'm not making an analytic-synthetic dichotomy; I've been speaking in terms of "a priori", "necessity", and "tautology". In essence, those such statements that have no need for context to determine their truth.

[Edited for bigger flavor.]

Edited by aleph_0
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The sentence, "All bachelors are unmarried males," is true by dint of what the sentence means to communicate. That is to say, simply by the meaning of 'bachelor', 'unmarried', 'male', and the standard English grammar, this is necessarily a true statement.
But the same is true of the sentence "All men are mortal" and "George Bush is the US President in 2006". As long as we understand that all true sentences are necessarily true, then we've got it covered.
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"George Bush is the President," is not true just by meaning--it requires both meaning and a context, namely, one in which George Bush is the President. There is nothing about the definition of 'George Bush', 'the President' and the appropriate English grammar that could have told you this is true. By no amount of logical reasoning could an African with no understanding of American politics have figured this out. He may perfectly well understand what you mean to say--that there is a man, his name is 'George Bush', he comes from Texas, and he is the Commander and Chief of the United States--but still not know the truth of that sentence. Conversely, he may simply know what you mean to say, when you say, "If George Bush is alive, then he is a man," and know the truth of the sentence regardless of any context. The concept that you are trying to communicate could not fail to be true, no matter what is in reality, so it is true simply by what you mean to say.

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Is there any proof of why human action is different than non-human action however? Stating that humans aren't predetermined like physical objects because humans have volition seems rather circular. Volition is simply the state or capacity of not being predetermined, no?

Did Ayn Rand ever attempt to prove why human action isn't predetermined?

I think David was using "predetermination" in a special sense here. There are many usages of "determinism." Human actions are, as everything else, subject to causality. But volition is a specific type of causality which is different from "mechanistic determinism" which is a causality that applies only to that which is subject to the laws of mechanics.

In ancient Greece, Democritus originated the idea that everything, including human action, is subject to mechanistic determinism, which is sometimes referred to as "billiard ball metaphysics" because everything would then be more or less a chain reaction caused by atoms bumping into each other. It was refuted by Aristotle, who defined causality in terms of the nature of the entities that act. Aristotle argued that human actions are "teleological," or goal oriented. Volition is a result of man's nature as a rational being. It is a causal process, by which a man focuses or unfocuses his attention on certain facts (that's the primary choice), and selects a course of action to obtain the goal he's set for himself.

The difference between human and non-human action is that, while humans act according to "final causation" (teleology), the material world opperates by "efficient causation" (every event is the result of antecedent causes). You could say, in a certain sense, humans act "because of the future" and inanimate nature acts "because of the past."

In short, the "proof" for the fact of human action being different from non-human action derives from the fact that only humans are capable of reasoning, and therefore making plans and setting goals. The fact that humans do this, can plainly be observed. And there is no reason to think, as Democritus (and his followers to this day) suggested, that this is merely "an illusion."

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"George Bush is the President," is not true just by meaning--it requires both meaning and a context, namely, one in which George Bush is the President. There is nothing about the definition of 'George Bush', 'the President' and the appropriate English grammar that could have told you this is true.
Sure there is: "President of the US" is defined as "The executive under Article I of the Constitition, which included George Washington, Thomas Jefferson, Geroge Bush and various other individuals after 2008". "George Bush" is defined as "The man born July 6, 1946 who was governor of Texas and was elected 43rd president of the US".

Now it look like we're back to the problem of meaning versus definitions, and I'd really like you to make up your mind whether you're talking about sentences which are true only in the context of a particular stated definition, or sentences that are true because of meaning. If you mean the latter, then don't invoke "definition". And do re-read the sections on meaning in ITOE. If on the other hand you are talking about truth as a function of definition, then as I have stated numerous times, there are many sentences which are true by definition, but the definition has to actually be given in order to know if the sentence is true by definition.

It would probably be better to pick clearer terms, since "true by definition" unfortunately has a certain currency in this analytic-synthetic discussion, referring to the mystey category of "analytic" sentences. Let's talk instead about "word-game truth", meaning the situation where you cook up a definition of some number of terms so that you can do a formal proof that the sentence is "T" (using the formal logical unit, which is entirely different from "true"). That is to be contrasted with "actually truth" sentences, namely descriptions of reality, for example the statement that Bush is president (without reference to a particular definition of "president") or that today is June 5, 2006. Interestingly, the actually true sentences turn out to be the ones that are necessarily true, because they describe facts, and because they describe facts they are necessarily true. In contrast, word-game true sentences sentences are contingently true -- they are only true relative to a particular definition.

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In ancient Greece, Democritus originated the idea that everything, including human action, is subject to mechanistic determinism, which is sometimes referred to as "billiard ball metaphysics" because everything would then be more or less a chain reaction caused by atoms bumping into each other. It was refuted by Aristotle, who defined causality in terms of the nature of the entities that act. Aristotle argued that human actions are "teleological," or goal oriented. Volition is a result of man's nature as a rational being. It is a causal process, by which a man focuses or unfocuses his attention on certain facts (that's the primary choice), and selects a course of action to obtain the goal he's set for himself.

The difference between human and non-human action is that, while humans act according to "final causation" (teleology), the material world opperates by "efficient causation" (every event is the result of antecedent causes). You could say, in a certain sense, humans act "because of the future" and inanimate nature acts "because of the past."

It has been a long time since I studied Aristotle, but I believe Aristotle's key distinction is between material objects and natural objects, not between natural objects and man. Aristotle believed that all natural things had a final cause. Aristotle would say that a bird or an insect was "for" something, for example. The difference between humans and animals is not a difference in causality but a difference in the type of soul each has. The human soul has additional capabilities in addition to those also possessed by animals and plants.

In short, the "proof" for the fact of human action being different from non-human action derives from the fact that only humans are capable of reasoning, and therefore making plans and setting goals. The fact that humans do this, can plainly be observed. And there is no reason to think, as Democritus (and his followers to this day) suggested, that this is merely "an illusion."

This is merely descriptive, however. Making plans and setting goals are just types of actions which still may have a pre-determined causal history. From what I can tell, you are basically saying that non-determinism is "self-evident" which I think is very dangerous.

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Aristotle believed that all natural things had a final cause. Aristotle would say that a bird or an insect was "for" something, for example.

Oh yeah. He was wrong about that part (See AR's article "The Metaphysical vs. the Manmade" for her correction to this mistake). [Edit: You can find that article in The Virtue of Selfishness.]

The difference between humans and animals is not a difference in causality but a difference in the type of soul each has. The human soul has additional capabilities in addition to those also possessed by animals and plants.
Right, fundamentally speaking. But the different types of soul result in different manisfestations of causality (which is defined as entities acting according to their nature).

This is merely descriptive, however. Making plans and setting goals are just types of actions which still may have a pre-determined causal history. From what I can tell, you are basically saying that non-determinism is "self-evident" which I think is very dangerous.

But I would argue against using the term "determinism" in this context. It's too much of a misleading word, because it has connotations both of implying "causal" (which human-actions are) and also of implying mechanistic materialism (which is a violation of the axiom of consciousness, therefore invalid as a concept). Using "determinism" instead of either "causal" or "machanistically determined" lends itself too much to the temptation to conflate the two ideas, which leads to disaster.

Edited by Bold Standard
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• 1 year later...

What are necessary and contingent propositions?

Edited by softwareNerd

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