The Instigator
Illegalcombatant
Pro (for)
Losing
1 Points
The Contender
larztheloser
Con (against)
Winning
3 Points

Can we know anything for certain ?

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Post Voting Period
The voting period for this debate has ended.
after 1 vote the winner is...
larztheloser
Voting Style: Open Point System: 7 Point
Started: 2/1/2011 Category: Philosophy
Updated: 6 years ago Status: Post Voting Period
Viewed: 1,998 times Debate No: 14630
Debate Rounds (3)
Comments (3)
Votes (1)

 

Illegalcombatant

Pro

The debate topic is "Can we know anything for certain ?"

I as the Pro will make the case that we can know something for certain

Con will make the case that we can't know anything for certain

Please note, there is no win by default here, both sides have a burden to carry

If you have any problems or concerns with the debate, post in the comments section, don't accept the debate then try to change it.

Opening argument..........

1) Something exists and we can know this for certain

It has been said that the first question of philosophy is why is there something rather than nothing ?. But why accept the built in assumption that something exists. If we can't know anything for certain and thus anything we believe has the potential to be false, then surely the assumption that something exists is subject to be being false..............or is it ?

If you doubt existence, whether your own or in totality, even if you doubt whether existence exists then this doubt, is something. If nothing existed, then doubts and doubts about existence would not exist.

Any doubts about existence, prove that something exists.

2) We can't know something for certain ?

If some one argues that we can't know anything for certain, then this raises the question, are you certain that we can't know something for certain ?

They have 3 possible answers

1) Yes
2) No
3) I don't know

If they answer yes, then this is self refuting, as they are claiming to know with certainty that nothing can be certain.

If they answer no, then they must concede that it is possible that we can know something for certain, thus refuting the claim that we can't know anything for certain.

If they answer "I don't know" then once again, they must concede that its possible we can know something for certain, thus refuting the claim that knowing something for certain is impossible.

In summary both proof of existence based on doubting of existence, and the refutations of the claim that we can't know something for certain, prove that we can know something for certain.

I look forward to Cons response.
larztheloser

Con

I'd like to thank my opponent for creating this topic and look forward to an interesting debate. In this first round I will respond to my opponent's opening argument and then make one of my own.

My opponent made two arguments. The first was that we can know for certain that something exists because we believe that nothing exists. There are two problems with this argument. The first is that since our belief that nothing exists is now wrong, our belief no longer exists. Seeing as our belief no longer exists, it is quite plausible that nothing exists, so the belief that nothing exists is again justified. As you can see, this is at best a circular argument - one moment the belief is justified, the second it is not. But at worst, it is downright fallacious, because my opponent says that a doubt can be known (for if doubt cannot be known, we cannot be sure that we doubt and therefore your argument's premise falls down). In fact, a doubt is not a belief or an abstraction, but an uncertainty. Therefore it is not a "thing" (http://www.google.com...). Doubt is a thing, for here all doubts are abstracted, but a doubt is not. Since doubt is not a thing, we cannot know for certain that something exists.

My opponent's second argument asks me whether I know for certain whether we can't know something for certain. My answer has to be no. Therefore, my opponent rightly points out, it must be possible that we do know something for certain. Cool. I have to admit that I agree ... it is a possibility. We just don't know whether there actually is something or not, and this argument does nothing to show it. In fact, all that this argument really is, is an appeal to uncertainty ... something along the lines of "we cannot be sure, so it must be."

To meet my burden of proof, I need to show that we cannot know anything for certain. Because I'm lazy, I'll use Zhuangzi's two and a half thousand year old argument (hey, it's not as though your cases were particularly innovative!) - the Butterfly Dream case. Simply put, it runs like this: Bob dreams he is a butterfly. Then he wakes up and he is Bob. The question is ... is he really Bob who dreamt he was a butterfly, or a butterfly dreaming that he is Bob? He has no way of knowing. The same thing can be applied to all things. Say I believe in free markets, and then have a dream that I am Joseph Stalin. Do I believe in free markets or communism? I cannot know. Or to use my opponent's own example. I doubt existence. Do I really doubt existence, or am I simply Jesus having a dream about someone doubting existence? I cannot tell. It is worth remembering that often, in our dreams, we are not aware that we are dreaming.

OK, so to sum up this very quick first round, my opponent's two arguments don't stand and I have made a quick case for why we can't know anything with certainty. Great. I look forward to hearing my opponent's rebuttals and the remainder of the debate!
Debate Round No. 1
Illegalcombatant

Pro

I thank Con for their response.

"My opponent made two arguments. The first was that we can know for certain that something exists because we believe that nothing exists"

I would point out that I had said we can doubt existence, but this just might be a semantic point on my part.

Con says " There are two problems with this argument. The first is that since our belief that nothing exists is now wrong, our belief no longer exists"

Their is a hidden premise in Cons argument, by Con saying "The first is that since our belief that nothing exists is now wrong" this implies that I had claimed that the claim that nothing exists was right in the first place, I had never made nor implied as such. This misrepresents my argument and thus is a strawman.

In fact what I had argued previously was "If you doubt existence, whether your own or in totality, even if you doubt whether existence exists then this doubt, is something. If nothing existed, then doubts and doubts about existence would not exist"

My argument here was to prove the self refutation of the claiming nothing exists, thus it was never justified in the first place.

I shall elaborate on this point, if some one claims that nothing exists, then this claim is its self something, thus self refuting.

Con says "Seeing as our belief no longer exists, it is quite plausible that nothing exists, so the belief that nothing exists is again justified"

Once again, claiming that nothing exists is self refuting, if nothing exists it would be impossible to claim nothing exists in the first place. The claim about nothing existing is its self something.

Con says " But at worst, it is downright fallacious, because my opponent says that a doubt can be known (for if doubt cannot be known, we cannot be sure that we doubt and therefore your argument's premise falls down)"

Even if you have a doubt, but doubt that doubt, that is still something and proves that something exists. Having doubts about doubts does not refute my argument, since I argued that once doubt is established, even doubts about doubt, that proves something exists and thus we can know for certain that something exists.

Con says " In fact, a doubt is not a belief or an abstraction, but an uncertainty"

I would ask Con what the difference is between a doubt and a belief is, since your say a doubt is not a belief.

You do claim that doubt is an uncertainty, I would ask you to explain in more detail on this. For instance if doubt = uncertainty, isn't it the case that uncertainty is its self something ? thus proving that doubt is something.

Con says "Since doubt is not a thing, we cannot know for certain that something exists"

I think this is untenable, is Con arguing that doubt is not a thing ? but if that is so, how can we have doubts in the first place if they don't exist ?

Con says "Therefore, my opponent rightly points out, it must be possible that we do know something for certain. Cool. I have to admit that I agree ... it is a possibility"

If its true that nothing can be known for certain, then the claim that we can know something for certain is false.

If its true that something can be known for certain, then the claim that we can't know anything for certain is false.

Consider this argument..........

1) If it is possible to know something for certain, the claim that it is impossible to know something for certain is false
2) It is possible to know something for certain (Con concedes this point)
3) Therefore the claim that it is impossible to know something is false
4) Therefore we can know something for certain

Con uses their butterfly dream analogy, but even if we accept it, what does it prove ? It merely proves that we can't be sure that we exist as we see ourselves, but I never claimed that the certainty of existence is based on whether we see our selves correctly or not.

Con says " Or to use my opponent's own example. I doubt existence. Do I really doubt existence, or am I simply Jesus having a dream about someone doubting existence? I cannot tell. It is worth remembering that often, in our dreams, we are not aware that we are dreaming"

Again, lets accept this argument, what does it prove ? once again that you might not see yourself correctly ? Once again I remind Con, even in this example, you are doubting the doubts you have, thus proving that something exists. If nothing existed then doubts and doubts about doubts, and doubts about doubts about doubts would not exist.

I thank Con for presenting their arguments about doubts, and doubts about their own doubts, even doubting the details of their own existence and even doubting whether they exist at all thus proving what I had said at the start...........

"If you doubt existence, whether your own or in totality, even if you doubt whether existence exists then this doubt, is something. If nothing existed, then doubts and doubts about existence would not exist"

Thus proving we can know something for certain, we can be certain that something exists.

I look forward to Cons reply.
larztheloser

Con

I'd like to thank con for thinking that he has continued his case, or so I think I would. I think I will respond to his two counter-arguments and criticism of my own case, which I think he has grossly misrepresented, though he doesn't think so.

== PRO'S ARG 1 ==

My opponent said I had misrepresented his case. Let's look at it again:

1 > "If you doubt existence" - assuming you doubt existence...
2 > "this doubt, is something." - then your doubt exists.

I was adding the logical follow-on steps that my opponent ignored:

3 > "If this doubt is something"
4 > "Then your doubt is wrong" - Thus you dismiss your doubt
5 > "Thus the doubt ceases to be"
6 > "This doubt, is nothing"
7 > "Now it is again possible that nothing exists"

What I was demonstrating was not that your argument was directly self-refuting, but leads to a logically self-refuting and circular claim. That is, your argument that doubt is something is itself self-refuting.

My second case you asked for elaboration on. Doubt is not non-belief in existence, rather, it is the uncertain position. A belief is saying "yes, I agree" or "no, that's wrong." A doubt is "I don't know." I don't know if we exist, so I doubt it. Hope this clarification helps. The point is that being uncertain is not a thing, as I justified last round.

Then my opponent says "but if that is so, how can we have doubts in the first place if they don't exist ?"
This is a clear red herring. How we think is a different debate from how we know. This is a debate about knowledge, not cognitive process.

== PRO'S ARG 2 ==

My opponent changes his tack slightly:

1) If it is possible to know something for certain, the claim that it is impossible to know something for certain is false
2) It is possible to know something for certain (Con concedes this point)
3) Therefore the claim that it is impossible to know something is false
4) Therefore we can know something for certain

Pro makes a mistake in premise one. A may be possible, and B might be possible. If A, then not B. My opponent is saying that if A is possible, then B is false. Any person who has studied logic will immediately see the flaw in that reasoning. Just because one thing is possible does not exclude the other alternative from being possible, and, this has no bearing on whether a given alternative is true. Two mistakes in one line of working.

== MY ARG ==

"what does it prove ? It merely proves that we can't be sure that we exist as we see ourselves"
Yes. You are right. So we cannot be sure of anything about existence. I had to prove that we cannot know anything for certain. With reference to existence, we cannot know if we correctly interpret how we exist, or even, whether we exist (we could be non-existent entities dreaming we exist, after all). It might be a dream, or of course, it might not be a dream, so we can't even be certain of the dream's existence. We just don't know anything. This is what it proves.

"Once again I remind Con, even in this example, you are doubting the doubts you have, thus proving that something exists."
Perhaps I am doubting, or perhaps I am an annoying fly with not a care in the world for epistemology dreaming it is a human doubting existence. What it proves is, again, that we cannot be sure of any knowledge because we cannot exclude the alternative theory, that we are in fact the absolute opposite in a dream.

== CONCLUSION ==

My opponent's cases are, in the first instance, self-refuting and wrong, and in the second, logically mistaken. By way of contrast, pro has already accepted that my case is correct but challenges me on what it "shows". I have provided clear analysis in this round to back up all of the above. I would once again like to take this opportunity to thank my opponent for having this debate with me, and look forward to the third and final round.
Debate Round No. 2
Illegalcombatant

Pro

I thank Con for their response.

I would like to go over their argument........

1 > "If you doubt existence" - assuming you doubt existence...
2 > "this doubt, is something." - then your doubt exists.

3 > "If this doubt is something"
4 > "Then your doubt is wrong" - Thus you dismiss your doubt
5 > "Thus the doubt ceases to be"
6 > "This doubt, is nothing"
7 > "Now it is again possible that nothing exists"

Even if we accept premises 1-6, the conclusion is self refuting. The conclusion says "Now it is again possible that nothing exists"

If nothing existed there would be no conclusions, once again denying existence only proves existence. Existence is necessary in order for something to deny and/or doubt whether existence exists.

Consider this argument.......

1) If something exists, then its not possible for nothing to exist
2) Something does exist (such as Con conclusion)
3) Therefore it is not possible that nothing exists

This refutes Cons conclusion that "7 > "Now it is again possible that nothing exists"

I had asked before ""but if that is so, how can we have doubts in the first place if they don't exist ?""

Con objects "This is a clear red herring. How we think is a different debate from how we know. This is a debate about knowledge, not cognitive process"

I asked about whether doubts exist or not, Con just refused to either confirm or deny. Either way, if they confirm doubts exist, then that proves existence, if they deny that doubts exist, but only something that exists can deny existence, thus proving something exists.

Before I had made an argument with the following premise................

"1) If it is possible to know something for certain, the claim that it is impossible to know something for certain is false"

Con made some objections here which I would like to address...... Con says "Pro makes a mistake in premise one. A may be possible, and B might be possible. If A, then not B. My opponent is saying that if A is possible, then B is false."

Con says "Just because one thing is possible does not exclude the other alternative from being possible"

Seeing that Con wants to bring logic into it, In logic, the law of excluded middle (also known as the principle of excluded middle or excluded middle or excluded third) is the principle that for any proposition, either that proposition is true, or its negation is.http://en.wikipedia.org...

Consider these propositions............

1) It is possible to know something for certain
the negation of this is
2) It is not possible to know something for certain

Only 1 of these claims can be true, they can't both can't be possible based on the law of excluded middle.

1) If it is possible to know something for certain, the claim that it is impossible to know something for certain is false
2) It is possible to know something for certain (Con concedes this point)
3) Therefore the claim that it is impossible to know something is false
4) Therefore we can know something for certain

Con says "Perhaps I am doubting, or perhaps I am an annoying fly with not a care in the world for epistemology dreaming it is a human doubting existence. What it proves is, again, that we cannot be sure of any knowledge because we cannot exclude the alternative theory, that we are in fact the absolute opposite in a dream."

This is a huge non sequitur...... consider cons argument........

1) We can't be sure of our own experiences (eg maybe we are a fly, a dream, in the matrix etc)
2) Thus our own beliefs of our reality might be false
3) Therefore we can't know anything

But notice here, they equate one type of uncertain knowledge (such as our own existence as a fly) then conclude NOTHING can be known for certain. That's a big jump to make consider this argument...

1) All ducks in Australia are black
2) Therefore all ducks in the world are black

Even if all ducks in Australia were black, this is no way proves that all ducks in the world are black, just like Cons argument that we can't be sure of our own existence therefore we can't be sure about anything.

Now lets go back to my proof of existence where I said..."If you doubt existence, whether your own or in totality, even if you doubt whether existence exists then this doubt, is something. If nothing existed, then doubts and doubts about existence would not exist."

No amount of arguments based on whether we perceive reality correctly or not refute my proof, and as such are strawman arguments.

Consider this, maybe we don't exist physically at all, maybe we are the product of a computer simulation. But still my argument applies, if you question/doubt existence then something has to exist in order for this doubt to occur. I never said YOU or I have to exist, just that something exists.

Thus doubting of existence proves existence, and thus we can be certain that something exists, both proving my case and refuting Cons case which is its impossible to know anything for certain.

What if all my arguments are wrong ? what if Con is correct in all they say maybe I should just concede that maybe their arguments are possibly correct, but if all my arguments are wrong this just proves once again that something exists. In this case wrong arguments exist.

In conclusion we can know something for certain, and that something is that something exists.

I thank Con for participating in this debate.
larztheloser

Con

I'd like to thank pro for attempting to salvage their case in the last round. Unfortunately I think it was too little, too late.

== PRO'S ARG 1 ==


My opponent tacitly accepts my elaboration on his argument bar the final line of working. He suggests that this is a conclusion, and that this exists. However, any careful reader will note that it is just the beginning. The moment that it is possible nothing exists, we doubt that something exists. Then, like my opponent states, something exists. Therefore, like my conclusion reasons, possibly nothing exists.

At no stage does the line "It is possible that nothing exists" logically equal "Something does exist," such as my opponent claims. My opponent asserted this in step two of his little 3-step fallback case and never backed it up. Therefore the case is invalid.

In round two, pro asked me "how can we have doubts." Now he claims he asks "whether doubts exist or not." On the second question, his original question presupposes the existence of doubts, so my opponent must either not be contending the point or contradicting himself. On the first question I have already given my response. I personally do not confirm or deny the existence of doubts, because I doubt the existence of doubts.

== PRO'S ARG 2 ==

My opponent tries to use the law of the excluded middle here. Clearly he is a bit slow, because I already used it last round. The law of excluded middle is that if A, then not B. In this case, however, my opponent confuses possibility for existence. Just because something can be true does not mean it is. So, I restate:

If A, then not B.
A is possible.
B is possible.

I not only conceed all of the above, but it was me who first brought it up. From this my opponent concludes A, and therefore not B. Why? Because A is possible. That is ridiculous. In fact, this has to be the most all-time ridiculous laughable argument I have ever heard - that just because something is possible it must be so.

== MY ARG ==

My opponent has decided to switch to a brand new case in the final round. He claims I am using some uncertain knowledge to justify all knowledge being uncertain. This is false. All knowledge is subject to this type of uncertainty. Not just knowledge about existence or gathered in Australia, but all knowledge is subject to the problem that we might not really have that knowledge, or that the knowledge might be false.

Then my opponent claims this is a strawman case. He says we can know that something exists, but all this argument proves is that we can't know what this something is. Well, to that I must simply ask - how do you know? Prove that a non-existent thing cannot dream it was actually real. Prove that dreams do not dream. Then I would abandon this argument. But as it stands, it is far from a strawman case. It shows that we cannot know things for certain. This includes something existing, because both my opponent and I have no conception of nothing existing.

== CONCLUSION ==

I doubt that we can know things for certain. Perhaps we can, and perhaps we can't. You might think I produced better arguments, but you don't know it. Thus we cannot know if something exists.

Please vote con.
Debate Round No. 3
3 comments have been posted on this debate. Showing 1 through 3 records.
Posted by larztheloser 6 years ago
larztheloser
Glad I made it fun for you.
Posted by Illegalcombatant 6 years ago
Illegalcombatant
I liked this debate, think ill set another up like it, haha.
Posted by Cliff.Stamp 6 years ago
Cliff.Stamp
Turning point was :

"But notice here, they equate one type of uncertain knowledge (such as our own existence as a fly) then conclude NOTHING can be known for certain. That's a big jump to make consider this argument...

1) All ducks in Australia are black
2) Therefore all ducks in the world are black"

If the nature of existence is uncertain, then the argument was made that all knowledge gained from existence is uncertain, the duck analogy does not hold trivially, you would have to argue that there is shared knowledge between the two at a minimum which can be known absolutely in both realities/existences (such as for example something exists and not nothing which could be claimed to be true in both).

Can did get a bit off neutral in the end, however only sightly so, weak point to pro on conduct.
1 votes has been placed for this debate.
Vote Placed by Cliff.Stamp 6 years ago
Cliff.Stamp
IllegalcombatantlarztheloserTied
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Total points awarded:13