Semantics and Truth

[Gurdur]

Can anyone think of a case where a statement is neither true nor false?

Any statement that is a general statement about subjective viewpoints is often neither true nor false:

any prescriptive statement avout preferences, aesthetics or ethics simply cannot be true nor false;

 

and there are a great many statements you can construct linguistically that are not true nor false.

 

"Green ideas sleep furiously"

"Thou shalt not kill"

"You should like broccoli"

"Twas brillig, and the slithy toves"

etc. etc. etc.

 

In fact, trying to make all statements have a truth value is not only impossible, it's illogical as well.

[bumab]

Any statement that is a general statement about subjective viewpoints is often neither true nor false:

any prescriptive statement avout preferences, aesthetics or ethics simply cannot be true nor false;

 

and there are a great many statements you can construct linguistically that are not true nor false.

 

"Green ideas sleep furiously"

"Thou shalt not kill"

"You should like broccoli"

"Twas brillig, and the slithy toves"

etc. etc. etc.

 

In fact, trying to make all statements have a truth value is not only impossible, it's illogical as well.

 

True. Then let me add to my statement:

 

"All statements about the world are either true or false"

 

So one could say "you think thou shalt not kill" that's true or false, or simply not specific enough to have an answer. How about: "you do not think it is right to kill in situation x" or "you do not think it is not right to kill in situation x" those are exhaustive statements- one shuld be true and the other false

[bumab]

It's false in Z. It's true in Z_13. It's false in Z_n for n other than 13.

 

But then the statement was not specific enough, and it's a question of definitions, not truth. I was assuming Z_13 (apparently ;)). So the statement was incomplete. But I get your point.

 

How about ab = c, true or false?

 

Again, not enough information. How do you define a, b, and c? it comes down to definitions!

[Qfwfq]

But then the statement was not specific enough, and it's a question of definitions...

Yes, of course, but it still is a statement. In your initial point you would therefore need to specify just as well, not only the statement but a well defined context. Not all contexts may be sufficient, either. Endless disagreements are often due to this type of trouble, they can also be due to us not knowing all facts on which to base a conclusive argument.

 

Does the Higgs boson exist?

[Tormod]

Does the Higgs boson exist?

 

If the Higgs boson thinks, it exists. ;)

[bumab]

Not all contexts may be sufficient, either. Endless disagreements are often due to this type of trouble...

 

If the statement is ill-defined, there is a context problem, but that's not a reflection on the truth of the statement, it just means the statement is ambigious.

 

 

Does the Higgs boson exist?

 

The statement would be "the Higgs boson exists." That is either true or false. We don't know, but it seems reasonable to conclude it either exists or it doesn't. Thus, that is a statement that is either true or false.

[Gurdur]

True. Then let me add to my statement:

 

"All statements about the world are either true or false"

 

So one could say "you think thou shalt not kill" that's true or false, or simply not specific enough to have an answer. How about: "you do not think it is right to kill in situation x" or "you do not think it is not right to kill in situation x" those are exhaustive statements- one shuld be true and the other false

No, there is a very basic misapprehension here.

A statement like "you should not kill" is a prescriptive statement.

A statement like "you do not think it is right to kill" is a descriptive statement.

 

Descriptive statements may have truth values, though not at all always (and in my previous post I gave examples of descriptive statements without truth values).

 

Prescriptive statements cannot have truth values.

 

Thus, a large amount of the statements we make about the world simply do not and/or cannot have truth values, which means the argument you want to make does not work.

[Qfwfq]

Alright, let's go back to the beginning:

Given this statement is true:

All statements are either true or false.

We have agreed that this begs the requisite of not only the statement itself, but the context being well defined.

 

If that is the case, then all arguments have a logical conclusion, and all philosophers should have the same, inetivable view.

 

Agree? Disagree?

With the requisites being fulfilled, philosophers eventually agree, after sorting out any doubts about inference. If the context is meant to be reality, the requisites include the axioms being certain and the inference rules sensible. It's a lot easier for philosophers to agree unanimously about a formal system. Reality isn't so easy to completely formalize and axioms will always be subject to verification or, as Popper prefers to put it, falsification.

[bumab]

Thanks Q- good summary. I appreciate the insight.

 

This leads into logical deteminism. Any thoughts on that?

 

Logical determinism (LD): At any point in time x, the future is fixed by a complete set of truth statements about the state of the world at any point in the future which exist at x.

[Gurdur]

This leads into logical deteminism. Any thoughts on that?

Logical determinism (LD): At any point in time x, the future is fixed by a complete set of truth statements about the state of the world at any point in the future which exist at x.

It doesn't just lead to logical determinism, it strongly implies total determinism of all kinds, including psychological determinism.

Let's look at why it doesn't work first off, and then I want to ask you just what goal you have in mind with all of this.

 

Now, the universe includes a component of randomicity, to the best of our knowledge. So straight off strong determinism is defeated; then we have the evolution of self-consciousness, the self-altering ability of self-referential intentionality, and we also have to top it all off the limits of knowledge.

 

Evereyone has a different POV, no-one can know everything (since to know everything is to mean a Turing machine larger than the universe), and everyone thus only knows a fragment --- and we haven't even got to the part that there are things that cannot be known.

If that is the case, then all arguments have a logical conclusion, and all philosophers should have the same, inetivable view.

So that would only be true even in an absolutely determinist world for cases where each participant had perfect knowledge about that particular case;

and gets less and less true as a case gets more complex, and is totally untrue about the world at large.

 

The argument only works even in an absolutely determinist world for extremely shallow, easy cases where perfect knowledge is possible;

and we know our world to include unknowable components and undecidable components, which is the deathblow to the argument.

[Qfwfq]

This leads into logical deteminism. Any thoughts on that?

Although I forget to explicitly mention it, I could have said philosophers will eventually agree whether an assert is true, false or undecidable in a given formal system. LD certainly applies in appropriate cases but doesn't extend to realistic determinism.

[bumab]

It doesn't just lead to logical determinism, it strongly implies total determinism of all kinds, including psychological determinism.

 

I'm not familiar with psychological determinism. What is that?

 

Let's look at why it doesn't work first off, and then I want to ask you just what goal you have in mind with all of this.

 

No point. To discuss an interesting idea. If I had a point, I'd probably be trying to convince people, and then I'd have a personal bias. I just want to get the idea across clearly, which I'm not doing very well, and hear some comments.

 

Now, the universe includes a component of randomicity, to the best of our knowledge. So straight off strong determinism is defeated; then we have the evolution of self-consciousness, the self-altering ability of self-referential intentionality, and we also have to top it all off the limits of knowledge. Evereyone has a different POV, no-one can know everything (since to know everything is to mean a Turing machine larger than the universe), and everyone thus only knows a fragment --- and we haven't even got to the part that there are things that cannot be known.

 

You've missed the point. It's not that people know which statements about the future are true. That has nothing to do with it. It is that true statements about the future exist and are true at this moment. Thus, it is true I will eat lunch before noon or it is true I will eat lunch after noon. One of those statements is true right now. I don't know which, but that doesn't stop one from being true. And thus, I am "determined" to do one or the other, by logical necessity. While this is determinism in the sense that it fixes the future to one set of true statements, it does not eliminate free will. While it's true I won't do something else, it's not true I can't do something else.

 

So that would only be true even in an absolutely determinist world for cases where each participant had perfect knowledge about that particular case;

and gets less and less true as a case gets more complex, and is totally untrue about the world at large.

 

I'm confused about this statement. Again, complexity and knowing are not the issue. If there are true statements about how the world will exist in the future (I do think there are these), then logically, the world will exist like that in the future.

 

and we know our world to include unknowable components and undecidable components, which is the deathblow to the argument.

 

I'm sorry you missed my point, hopefully this clears it up.

[Queso]

Does the Higgs boson exist?

 

if it didn't, it does now. ;)

[Gurdur]

You've missed the point. It's not that people know which statements about the future are true. That has nothing to do with it. It is that true statements about the future exist and are true at this moment. Thus, it is true I will eat lunch before noon or it is true I will eat lunch after noon. One of those statements is true right now. I don't know which, but that doesn't stop one from being true. And thus, I am "determined" to do one or the other, by logical necessity. While this is determinism in the sense that it fixes the future to one set of true statements, it does not eliminate free will. While it's true I won't do something else, it's not true I can't do something else.

......

I'm confused about this statement. Again, complexity and knowing are not the issue. If there are true statements about how the world will exist in the future (I do think there are these), then logically, the world will exist like that in the future.

I'm sorry you missed my point, hopefully this clears it up.

Not really, I still fail to see what point you want to make at all.

For example, your statements about "true statements" about the future again are just not so.

For example, you could die before having lunch.

 

So you need to vastly increase your statements about the future by including all possiblities, or you need to use the word "probably" in your statements.

 

SO exactly what is your aim here ?

[bumab]

Again-

 

The statement "I will eat lunch before noon" is either true or false. If I die before noon, it's false- no problems there.

 

Are you asserting there are no true/false statements about the future? I don't think one can- see the lunch example.