Let's put this common refrain to rest~ something that I hear all the time in arguments concerning religion.  It goes something like this:

" Remember, you can't prove a negative!"

Really people?

This has become much more common, especially in the arguments amongst Atheists and agnostics concerning certainty, and it really puzzles me how people can be skeptical and free-thinkers, yet take to an idea so easily and not question it.  I will elaborate on this a little more once I have the time, but let me start all of those "can't prove a negative" types off with a question~ " I am not sitting at my desk."  Thats a negative claim.  Are you telling me that there is no way to confirm or disprove that?

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The rejection of a priori knowledge has historical precedent, so it's not an unreasonable stance to take, even though I consider it to be less effective than a broader view.


If I were to restate Cane's position, I would say that he is "certain in the belief that no means for proving a negative statement will be found by evidentiary means." He made a non-evidentiary prediction, not a binding conclusion, and that's valid to extent that his approach allows exclusions.

Drake, have you been following the "100% Positive" thread? http://www.atheistnexus.org/forum/topics/is-everybody-100-positive


Cane has been posting there relentlessly, refusing to acknowledge the simplest points, but rather persisting in pushing bizarre and idiosyncratic definitions, despite repeated demonstrations of his simple logical errors. He may not actually be a troll, but it is not too soon to suspect him of it.


You say, "if his approach missed something critical, then we should argue for an expansion of his ideas". We did that, repeatedly and extensively. I apologize for not being infinitely patient, but I am not an infinite being.

In science, you can be wrong or right. In logic, your idea can be possible, existent, or impossible. Logic is whether it is possible for something to exist in the real world. Science answers if something is in the real world. They are incompatible and that is why we disagree. With science, you cannot prove a negative. And apparently, in logic, it does not make sense to say you cannot prove a negative. Or at least, "You cannot prove a negative" is a self-negating proposition (whatever that means).

Cane, if you truly believe that science and logic are incompatible, then you understand neither. Again, your bizarre definition of logic is confusing you. It's impossible to do science without logic. Logic is a fundamental underpinning of the scientific enterprise. If this were not true, then scientific conclusions could not exist. Logic is how you get from hypothesis to evidence to conclusion.


And by self-negating proposition, I mean simply that if the proposition is true, it must be false. Which is definitely the case with "you cannot prove a negative". This statement is itself a negative. For it to be true, it would have to be false. This is not the kind of thing you want to base your reasoning on.

Hi Jason,


I actually find that to be a fairly cheap evasion. First of all, I think you're blurring the line between something being true and something being proven true. For instance, the statement "you cannot prove a negative" may well be true. This does not create a logical contradiction unless you actually claim that you can prove the statement "you cannot prove a negative".

This is analogous to our inability to prove certain mathematical theorems, despite them being almost certainly true. The inability to prove something is distinct from whether or not it is actually true. And the same goes for many subjective facts about us.


Besides, the whole business of self-negating statements gets fuzzy anyway.

One of the ones I often hear is the comeback to "Absolute knowledge does not exist.", which is "Is that an absolute claim?". But it's cheap: that statement may well be absolutely true, despite our logical inability to hold it as an absolute.


I find "You cannot prove a negative." to be a perfectly intelligible statement.

Matt, that's a fair criticism, but even if "you cannot prove a negative" isn't strictly self-negating because it does not contain its own disproof, it is a terrible axiom to adopt, since there are plenty of counterexamples to be had. Further, if it isn't strictly self-negating it heavily suggests that it isn't true. At minimum, people should not be blindly spouting it as though it were an obvious truth.

You do not understand what I mean by prove. To prove something exists, I need evidence. You don't. To prove a negative with evidence cannot be done because when your fruitless search ends, you can say the evidence is still yet to be found.

But if you prove with evidence that A exists, then not A is also proven by that evidence. So if you prove with evidence X, what would X have to be so that you prove god does not exist. X is a myth so far but I believe attainable.

We disagree on what proof is, on what Identity is, on what knowledge is, so I do not think being a troll in your opinion is such a bad thing. We have a very different view of the world and my view is as valid as yours.

I do not see where my "mistakes" are. I do agree that I have a belief that you cannot prove a negative. And you have not proven to me that your identities and priori knowledge are more than agreed upon definitions you call knowledge.

Cane, please! You say, "To prove something exists, I need evidence. You don't." This is simply not the case. Michael and I have repeatedly agreed with you that to prove something exists, you need evidence. Our assertion is that to prove something doesn't exist, you need only prove that it is logically contradictory/impossible. Can you truly not grasp the difference? Or are you doing this on purpose? Can you see why I have lost my patience with you? If you won't even bother to notice where we do actually agree, what is the point of discussion? At minimum, Cane, you need to get this distinction and apologize for putting words in our mouths.


And when you say, "We have a very different view of the world and my view is as valid as yours," this is simply postmodernist relativism, which is definitely logically self-negating. If all views are equally valid then so is the view that not all views are equally valid. If it's true it's false. One of us is wrong about certain areas of disagreement, and I'm inclined to think it's the one making up his own idiosyncratic definitions of things like logic and belief, rejecting more mainstream definitions. If you go around using home-grown definitions for common words, you are unlikely to properly understand the world, let alone make yourself understood by others.


Perhaps these two flagrant examples of your mistakes will give you some clue about why we are having such difficulty, but I'm not holding my breath.

Ok, I forgot that you agree with me on evidence being required to prove something exists. Mistake number one. I admit it.

I must also apologize for frustrating you folks. I am frustrated as well. We cannot seem to get our ideas across to each other, but I will try again.


What does not sit well with me is that you can prove (without evidence) that something contradictory is impossible. Logically and without evidence, you are just calling a definition wrong. I do not see how your contention that it is impossible really means anything. I agree that something contradictory to what it means to exist cannot exist itself, but that is a definition, not proof. I do not understand your definition of proof. For me, proof is provided by evidence.

Cane, you don't think it strange that you reject the entire class of logical proof? Mathematical proof, geometric proof? None of these things require evidence, only logical reasoning from axioms. To say these are not proofs is to simply disregard a standard definition of the word in favor of your own idiosyncratic definition. Why would you think that is acceptable?


Many things are disproven by definition. That's pretty much what we're talking about here. If you define things such that they contain logical contradictions, then they can't exist--they contain their own disproof within their definitions. Again, no evidence is required. You can call these "wrong definitions", but if these are the definitions that most people are using regarding these entities, then "wrong definitions" are the crux of the problem. Further, "wrong definitions", by definition, can't exist. It's silly to think that they might. If the gods worshipped by actual humans are illogical as the worshippers themselves define them, then whatever they are worshipping, it isn't what they think it is. They might be worshipping something else that could possibly exist, and maybe that is what you are saying, but they can't possibly be referring to a real entity with "wrong definitions".

I see a small indication that you understand me even though you do not agree with me. 

I would like to offer you my understanding of what a definition is and I would like you to compare it with your understanding of what identity is.

To me definitions are just descriptions that evidence could match or not.

I will tell you why I ask you this: I agree that something defined wrong cannot have matching evidence, so it can not and does not exist. Can I get to the same conclusions you arrive at with my understanding of definition as you do with your understanding of identity? If not, why not?

Or, you could look up some words in the dictionary, and use them the same way that everybody else uses them, and then we wouldn't have to translate back and forth from English to Cane-speak. You are really working way, way too hard at this, Cane.


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