Is this always the case? "Paradise" is synonymous with "Heaven", but "He knows that Paradise is Heaven" can be false while "He knows that Heaven is Heaven" is true.

I tried. "I can give you an argument, but I cannot give you understanding". Samuel Johnson.

By the way, do you (or others) know what the word "synonymous" means? To begin with, things (like knowledge or belief, or chairs and tables) cannot be synonymous. Only words can. Are the words "belief" and "knowledge" synonymous? Of course not. The test of synonymy is the salvae veritate test. "X" and "Y" are synonymous if and only if "X" and "Y" are intersubstitutable in every context preserving truth. But the words, "belief" and "knowledge"(or their cognates) cannot be substituted for each other in every context preserving truth. Therefore they are not synonymous. Example" "A believes that Quito is the capital of Ecuador" may be true, but, "A knows that Quito is the capital of Ecuador" may be false. So, "believe" and "knowledge" cannot be substituted for one another, salve veritate. Therefore, they are not synonymous. QED

I can't think of a single case of synonymousity with that criterion and opaque contexts such as the one you cited. That is interesting.

---------- Post added 02-07-2010 at 07:02 PM ----------



Careful with sentences like "To begin with, things (like knowledge or belief, or chairs and tables) cannot be synonymous. Only words can.". People might interpret that as logical impossibility or something else. I think that what you mean is this "To begin with, things (like knowledge or belief, or chairs and tables) cannot be meaningfully said to be synonymous. Only words can meaningfully said to be.".

That latin phrase seems completely unnecessary to me. Wiki. I am inclined to think that we should do away with/stop using it.

I tried. "I can give you an argument, but I cannot give you understanding". Samuel Johnson.

By the way, do you (or others) know what the word "synonymous" means? To begin with, things (like knowledge or belief, or chairs and tables) cannot be synonymous. Only words can. Are the words "belief" and "knowledge" synonymous? Of course not. The test of synonymy is the salvae veritate test. "X" and "Y" are synonymous if and only if "X" and "Y" are intersubstitutable in every context preserving truth. But the words, "belief" and "knowledge"(or their cognates) cannot be substituted for each other in every context preserving truth. Therefore they are not synonymous. Example" "A believes that Quito is the capital of Ecuador" may be true, but, "A knows that Quito is the capital of Ecuador" may be false. So, "believe" and "knowledge" cannot be substituted for one another, salve veritate. Therefore, they are not synonymous. QED

But the truth-value of "Jefferson City is the capital of Missouri" can be changed in two ways: by changing the meaning of the words (symbols), or by keeping the meaning the same and making an official decision that the city referred to as "Jefferson City" shall cease to be the capital.

The truth-value of "1+1=2", however, can only be changed by changing the meanings of the symbols. Given their current meanings, 1+1 cannot be made to equal anything other than 2 by mere stipulation, or by any other event.

If I had to anticipate the ways people might misinterpret (on this Forum) I could never begin to post. "Salvae Veritate" is the customary way of referring to this principle.

You really have no idea what I'm trying to say... Your "I tried" has been aimed at correcting an idea I already understand. I'm using the idea of knowledge and belief being synonymous to make a point, and if you can't see past the error that I already know I'm making, then you have no chance of understanding the argument that follows (which is in no way dependent on knowledge and belief being synonymous words).

---------- Post added 02-08-2010 at 02:07 AM ----------

That's right, but you can still avoid many misunderstandings by not using shorthands such as the one you used there. Besides, maybe you should look up the this even though the quality of that article is low.

Yes, it may be customary (I don't know but you do) but that is insufficient reason alone, I think, to use the phrase.

I also do not understand why there is a distinction between a necessary truth and a truth... to me the difference seems arbitrary, because I do not agree that there is a difference between the truths of 1+1=2 and Jefferson City is the capitol of Missouri. Both can be changed, they are merely symbolic... Look, I understand you will probably reply by explaining the difference between necessary truth and truth, but I know that already, my objection arises out of what I take will be a disagreement about what can be distinguished as reality, and also a disconnect I see as the symbolism of words is taken literally.

Scottydamion - Sorry, I do not understand your point. This is what you said:



If you know the difference between necessary truth and truth, how do you not understand "why there is a distinction" between them? Can you clarify your position, please?

I was trying to explain that there is, in my opinion, a difference between the truths of "1+1=2" and "Jefferson City is the capital of Missouri". If you think my argument on this point is wrong, I would be interested to know why.

I am not clear as to what you mean by "by changing the city you are changing the symbolism representing the capital of a state". I wonder if we are using the word "symbolism" differently. To me, "symbolism" refers to the representation of a thing by a word or symbol. Changing the name of a city would therefore be a change of symbol(ism), but changing the city itself (i.e. the thing referred to) would not.

Consider an example. I claim to know that Quito is the capital of Ecuador. And it is the capital of Ecuador.

Kennethamy - I'd like to pick up a small point in your post #265:



So:
1. You claim to know that Quito is the capital of Ecuador.
2. It is the capital of Ecuador.
3. You don't have to be certain in order to claim to know. You are not infallible.

From (3) we get:

4. It is (remotely) possible that Quito is not the capital of Ecuador.

Now, doesn't (4) contradict (2)? Aren't you saying, in effect: "Quito is the capital of Ecuador, but it possibly isn't"? This is, I think, why people keep bringing up the issue of certainty.

I agree that you don't have to be certain in order to claim to know. But a problem arises when you make categorical statements such as "And it is the capital of Ecuador". This is like saying: "Of course I might conceivably be wrong, but actually I'm not"! You are simultaneously adopting a subjective and an objective view.

So I think it would be better to express your example conditionally:

"I claim to know that Quito is the capital of Ecuador. And if it is the capital of Ecuador, then I do know it."

Kennethamy - I'd like to pick up a small point in your post #265:



So:
1. You claim to know that Quito is the capital of Ecuador.
2. It is the capital of Ecuador.
3. You don't have to be certain in order to claim to know. You are not infallible.

From (3) we get:

4. It is (remotely) possible that Quito is not the capital of Ecuador.

Now, doesn't (4) contradict (2)? Aren't you saying, in effect: "Quito is the capital of Ecuador, but it possibly isn't"? This is, I think, why people keep bringing up the issue of certainty.

I agree that you don't have to be certain in order to claim to know. But a problem arises when you make categorical statements such as "And it is the capital of Ecuador". This is like saying: "Of course I might conceivably be wrong, but actually I'm not"! You are simultaneously adopting a subjective and an objective view.

So I think it would be better to express your example conditionally:

"I claim to know that Quito is the capital of Ecuador. And if it is the capital of Ecuador, then I do know it."

But it is possible that Quito is not the capital of Ecuador, in at least two ways. It is logically possible, since the negation is not a contradiction; and it is epistemically possible, since our evidence for the proposition is inductive and not deductive.

I did not say you don't have to be certain in order to claim to know (in fact, I think you should be pretty sure if you claim to know, otherwise you would be misleading). I said that you don't have to be certain in order to know. Quite a different thing.

(Claiming to know is one thing, but knowing is a very different thing, and they are independent of one another. A major problem is that they are often confused. As above).

---------- Post added 02-08-2010 at 03:43 PM ----------



Careful with that epistemic possibility notion. It can mean two things, at least: 1) that you (or someone else) are not epistemically certain that P. 2) That it is epistemically possible that not-P. These are easily confused. The latter would contradict your knowledge claim. I think you mean the first. If you do, then I agree with you.

Also careful not to conflate psychological certainty with epistemic certainty.

If it is right, then you can be sure I mean it. But if it is wrong, you can be sure I don't mean it. That's a foolproof method for telling whether I mean one interpretation of another. (I agree about "epistemic possibility).

Hah. We agree about everything then!

Kennethamy - I'd like to pick up a small point in your post #265:



So:
1. You claim to know that Quito is the capital of Ecuador.
2. It is the capital of Ecuador.
3. You don't have to be certain in order to claim to know. You are not infallible.

From (3) we get:

4. It is (remotely) possible that Quito is not the capital of Ecuador.

Now, doesn't (4) contradict (2)? Aren't you saying, in effect: "Quito is the capital of Ecuador, but it possibly isn't"? This is, I think, why people keep bringing up the issue of certainty.

I agree that you don't have to be certain in order to claim to know. But a problem arises when you make categorical statements such as "And it is the capital of Ecuador". This is like saying: "Of course I might conceivably be wrong, but actually I'm not"! You are simultaneously adopting a subjective and an objective view.

So I think it would be better to express your example conditionally:

"I claim to know that Quito is the capital of Ecuador. And if it is the capital of Ecuador, then I do know it."

I flipped a coin, and it landed on either heads or tails, but you don't know which side it landed on, but you know that the following propositions are true:

P1: The coin is possibly on tails.
P2: The coin is possibly on heads.

Then, you look at the coin, and now you know the following propositions are true:

P3: The coin is on tails.
P4: The coin is not on heads.

Now that you have knowledge and know what side the coin is on, you make the mistake of thinking that P2 is false-a mistake you didn't make when you didn't know what the coin landed on.

The lesson is: Don't let your knowledge of what is the case distract you from knowing what is possibly the case.

If P3 is true, how can P2 be true? How can it possibly be on heads, if it is on tails? You're claiming the truth, that the coin is on tails, is possibly not the truth? We should always consider that the truth isn't the truth, even after we know the truth?

The two sides of the coin imply two possibilites, but after the coin is flipped, it's not a matter of possibility anymore. It is on either side. P1 and P2 don't apply to a flipped coin, do they? Perhaps they only apply to a flipping coin.

Or perhaps you are correct.

You may want to look up the definition of logical possibility.

Suppose you don't know the capital of Peru and I say that it might be Lima. The following propositions are true:

P1: The capital of Peru is possibly Lima
P2: The capital of Peru is possibly something else.

Then, you discover that the capital of Peru is Lima, so the following are true:

P3: The capital of Peru is Lima.
P4: The capital of Peru is not other than Lima

That P3 is true doesn't imply that P2 is false.

Why would I do that, when I know what logical possibility is? In fact, I have used the term in many of my postings. Perhaps you just want me to refresh my memory as a nice gesture. Thank you for the sentiment.

The issue is that I have qualms in regards to the term's practical application.

If someone flipped a coin, showed me it was heads, and then told me, "Well, it's possibly tails", I would think that person mad. I would say, "No, it's not possibly tails, it is heads". It would be essential that the person clarified the matter by making sure I understood he was speaking of logical possibility, that is, a non-contradiction. When we ordinarily use the word "possibility", I think plausibility is involved.

Really, you must clarify you're speaking of logical possibility. If you don't clarify, you'll get some looks.

PS: This is the sort of thing that makes philosophy seem so impractical. Logical possibility just means logically coherent, without contradiction. Confusing it with how people ordinarily use "possibility", and more, trying to pawn it off as ordinary usage, angers me. I'm so enraged, I don't know what to do with myself. I think Robert Deniro said that last part.

Ain't noone buyin' this stuff in rl, guys.

Jumping 50 feet straight up in the air (unaided) is possible in one sense of the term. It's possible in that it's logically possible-since it's not a contradiction.

Jumping 50 feet straight up in the air (unaided) is not possible in one sense of the term. It's not possible in that it's not a real possibility-who can jump that high?

Jumping two feet straight up in the air (unaided) is possible in both senses of the term. It's not only logically possible, but it's a real possibility as well.

The same with the coin example; both landing on heads and landing on tails (but not at the same time, of course) is both a logical possibility and a real possibility.

Yet, you would still say: "It's not really possible that it can be on heads if it's on tails," but that's different than it's not really on heads if it's on tails. What sense of "possible" would you be using?