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@Athias
Philosophy doesn't presuppose the validity of logic?
It usually does. However, it is also the only field (that I can think of) that would be willing to question that presupposition.
Is logic valid?
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@SirAnonymous
It usually does. However, it is also the only field (that I can think of) that would be willing to question that presupposition.
Which branch of philosophy (or philosopher) however unusual questions the presupposition that logic is valid?
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@Athias
Which branch of philosophy (or philosopher) however unusual questions the presupposition that logic is valid?
None that I know of. It's not a very useful topic to discuss because it has no practical effect.
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@SirAnonymous
No, there's no practical effect because the starting point for philosophy is reason. Logic is a mechanism that indexes the consistency of reason to selected truths. (Logic doesn't create truth.) So when you ask "is logic valid?" you're assuming an objective truth which logic doesn't presume to inform.None that I know of. It's not a very useful topic to discuss because it has no practical effect.
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@SirAnonymous
Given what you have concluded in the start of the thread don't you think this can apply to your Religion as well?
Do ask if you want me to tailor the thing you did at the start to your Religion.
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@TheRealNihilist
It would apply to everything. Theism, atheism, string theory, 2+2=4, etc.
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@SirAnonymous
It would apply to everything. Theism, atheism, string theory, 2+2=4, etc.
So how do you know Protestantism is valid?
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@TheRealNihilist
Logically, I can't be certain that it or anything else is valid. However, this whole thing about not knowing whether logic is valid is mostly just a thought experiment that has no practical effect other than being a weird type of gotcha for people who are a little too certain they're right.
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@SirAnonymous
What was the answer specifically towards your Religion?
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@TheRealNihilist
It wasn't specific to my religion, but it would apply to it. However, it would apply equally to your atheism. That's why it has no practical effect, because it invalidates everything equally.
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@SirAnonymous
Okay then I would be an agnostic. I am perfectly okay with that. What would you be?It wasn't specific to my religion, but it would apply to it. However, it would apply equally to your atheism. That's why it has no practical effect, because it invalidates everything equally.
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@TheRealNihilist
Still a Christian. Simply because I wouldn't be certain that it is true doesn't mean that it isn't true. It could still have a 99.999 percent chance of being true. Not certain just means not 100 percent.
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@SirAnonymous
I can use this exact same argument for my case. What makes yours more true?Simply because I wouldn't be certain that it is true doesn't mean that it isn't true.
It could still have a 99.999 percent chance of being true. Not certain just means not 100 percent.
Are you saying you know for sure God exists as in 100% or 99% sure or something else?
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@TheRealNihilist
I can use this exact same argument for my case. What makes yours more true?
Nothing, so far as the validity of logic is concerned. It applies to everything equally.
Are you saying you know for sure God exists as in 100% or 99% sure or something else?
Yes, but this is totally off topic. Why are you making this about religion? It's a philosophical thought experiment meant to show how you can't be certain about anything because you can't be certain about logic.
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@SirAnonymous
It's a philosophical thought experiment meant to show how you can't be certain about anything because you can't be certain about logic.
I am simply showing the real life examples of philosophy. If we take this theory and apply it to the real world. We realize we can't be certain God exists.
Do you want me to speak to you in another thread?
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@TheRealNihilist
I am simply showing the real life examples of philosophy. If we take this theory and apply it to the real world. We realize we can't be certain God exists.
If it's valid, we can't be certain of anything. Why single out God?
Do you want me to speak to you in another thread?
No, I don't have time for a "Does God exist?" debate right now.
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@SirAnonymous
Wouldn't you consider God to be one of the most important questions?Why single out God?
No, I don't have time for a "Does God exist?" debate right now.
Okay.
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@TheRealNihilist
Wouldn't you consider God to be one of the most important questions?
I consider it the most important question, but there are times when I want to talk about something else, like whether or not logic is valid.
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@SirAnonymous
Logic is valid just not valid inherently like with pretty much anything in the world. It is the most valid thing we have in gaining information.I consider it the most important question, but there are times when I want to talk about something else, like whether or not logic is valid.
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@TheRealNihilist
Logic is valid just not valid inherently like with pretty much anything in the world. It is the most valid thing we have in gaining information.
I agree. I just don't see how we can prove that it's valid. However, I don't think it really needs to be proven.
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@SirAnonymous
Okay.
Oh my god! If atheists could only comprehend this!I consider it the most important question, but there are times when I want to talk about something else, like whether or not logic is valid.
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@SirAnonymous
Logic Board - Mac
Mother Board - PC
Father Board - has all the gold ergo makes all the rules of logic ergo Drafterman states it correctly i.e. logic is only valid so far as the set of parameters its is framed within.
Universe's set of cosmic laws/principles do not contradict each other, operative everywhere and everywhen ergo eternally existent.
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@SirAnonymous
I used this argument in a different forum and decided that it needs its own topic simply because it is so unusual and counter-intuitive.There is no way to be certain that logic is valid. We can divide any possible argument into the two categories of logical and illogical. Since anything that is not logical is by definition illogical, and vice versa, these are the only two possible categories. My argument follows inevitably from these simple and indisputable premises.P1: Every argument is either logical or illogical.P2: Any attempt to use logic to prove that logic is valid is circular, because the use of logic presumes that logic is valid.C1: It is impossible to use logic to prove that logic is valid.P3: Any attempt to use illogic to prove that logic is valid is inherently contradictory.C2: It is impossible to use illogic to prove the validity of logic.C3: Because of P1, C1, and C2, there is no possible argument that can prove that logic is valid.As a result, no matter how self-evident logic seems or how well it is supported by the evidence, we cannot prove that logic is valid because such arguments are logical and therefore circular. Since it is impossible to be certain that logic is valid, and since all knowledge is dependent on the validity of logic, it is impossible to be absolutely certain that knowledge is true. Consequently, knowledge cannot exist, since any knowledge would be based on the uncertain assumption that logic is valid.So what do you think? I'm guessing we all agree that logic is valid, but do you think it's possible to prove that logic is valid? Is my reasoning correct, or does it have a flaw(s)?In other words, can we prove logic is valid, or do we just have to assume that it's valid out of necessity?
Logic is NECESSARY for making sense of anything. You need to assume it to communicate or prove anything else. Thus, it is a self-evident truth.
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@PGA2.0
@ebuc
I agree. It's just that I can't prove it's valid. Yes, it applies everywhere. Yes, it's self-evident. However, can you prove that it's self-evident or that it applies everywhere? We are forced to assume those things in order to make sense of the world, but even that assumes that the universe can be made sense of.
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@SirAnonymous
It's just that I can't prove it's valid.
Proof is in the pudding i.e. the resultant you desire, arrives via your logic, then no worries.
Yes, it applies everywhere.
That only applys in a cosmic scnario, not local scenarios that have differrent frames of reference.
However, can you prove that it's self-evident or that it applies everywhere?
We have no evidence.
......even that assumes that the universe can be made sense of.
Is there some aspect of Universe you dont understand? Even if you dont understand others do or may claim that they do.
Scientists claim there exist 1st law of thermodynamics because no evidence of other such conclusions exist to date.
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@ebuc
Proof is in the pudding i.e. the resultant you desire, arrives via your logic, then no worries.
I don't disagree. This is mostly a thought experiment that has very little practical application.
Is there some aspect of Universe you dont understand? Even if you dont understand others do or may claim that they do.
Well, no one understands all of the universe, so yes, there are aspects of the universe I don't understand.
Scientists claim there exist 1st law of thermodynamics because no evidence of other such conclusions exist to date.
I agree, but this illustrates my point. This is a logical statement. Using logic to show why logic is valid is circular.
To be clear, I'm not saying that logic isn't valid. It's just that we can't prove it, so we can't be 100% certain, just 99.999...% certain.
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@SirAnonymous
I agree. It's just that I can't prove it's valid. Yes, it applies everywhere. Yes, it's self-evident. However, can you prove that it's self-evident or that it applies everywhere? We are forced to assume those things in order to make sense of the world, but even that assumes that the universe can be made sense of.
Is not the necessity of logic proof enough (it is self-evidently necessary)?
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@PGA2.0
Perhaps.
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@SirAnonymous
One can logically conclude with 100% certainty that the universe exists. So, in at least one example, logic can be proven to be 100% valid.I'm not saying that logic isn't valid. It's just that we can't prove it, so we can't be 100% certain, just 99.999...% certain.