Mdthbs

Everyone starts out at 0 and if anyone wants to say that they know something they have to prove that claim. Is the counter to this person claiming that they know something logically correct?

Person 1: 'I know that the sky is blue.'

Person 2: 'You cannot prove that we are not in a simulation and that anything is real, hence you cannot prove that your claim was true.'

Writing this I feel that it is a logical fallacy, but I am incapable of thinking it through myself. Could anyone tell me if this is correct or not?

Edit: Thanks for all the replies. You guys said alot of interesting things I'll have to think about

If a person claims to know anything could it be disproven by saying 'prove that we are not in a simulation'?

Yes, and this his is a very simple logical point.

"I know that p" implies "p is true". This is fundamental to the concept of knowledge.

And if p is true, then there is no possibility that p is false. Thus, if I know that p, then there is no possibility that p be false. However, if you don't know that there is no possibility that p be false, then you cannot exclude that p is false, and therefore it is possible, for all you know, that p be false, which falsifies your claim that you know that p is true.

Please note the distinction between not knowing that there is no possibility that p is false, and p actually being false, just as there is a distinction between ignoring that p is false, and p actually being false.

Thus, an argument from ignorance can only at best falsify a claim to knowledge, not whether what is claimed to be true is in fact false.

We all claim to know things all the time and very often when we don't in fact know what we are talking about. For example, some Joe may claim to know that monkeys don't fly. Suppose now that the next day a new species of monkeys is discovered and that these monkeys do fly! This would falsify the claim that monkeys don't fly and therefore Joe's claim that he knew that monkeys don't fly.

However, the most important point is that although Joe's claim is falsified only the next day, his claim was in fact already false the moment he made it. Thus, Joe didn't know, and never knew, what he had claimed to know that monkey didn't fly.

Usually, we genuinely believe we know what we claim to know. Yet, experience shows again and again that we can be wrong, and it is the simple possibility of being wrong, even if it is that we might be wrong, which falsifies our claims to knowledge.

I know that p implies that p is true. If I know p, then p is true. And if p is true, then there is no possibility that p is false. But if I don't know that there is no possibility that p is false, I don't know that p is true, which falsifies my claim to knowledge.

That in itself won't stop people claiming they know. This is entirely a practical matter.

In effect, whatever we believe we know to be true may in fact be false and there isn't much we can do about that. Most of the time, however, if you are somewhat conservative and prudent and reasonable in whatever claims you make, you won't be contradicted by the facts of the matter.

It is a fact of life that we will claim that p whenever we happen to believe with a high enough degree of confidence that p is true.

Thus, even though most of the time we don't know that p, we will nonetheless claim that p just because we believe that p, and because from experience we believe that most of the time, we won't be contradicted by the facts of the matter.

In practice, it is worth claiming you know all sorts of things again and again, even if it is not true that you know them, because if you are reasonable in your claims, experience shows that you won't be contradicted so often as to damage your standing in society. In other words, we don't feel like we need to fuss too much about our claims to knowledge.

This only apply to everyday life but it is everyday life that drives the way we use basic words like "know" and "believe". Hence, we will use the word "know" even when in fact we only believe, and this merely because we also believe we will get away with it, at least most of the time.

There is another aspect to the question, though, somewhat more subtle, but your question is right on spot.

An argument from ignorance should identify a possibility and not everything will do in that respect. For example, if you say, well, you don't know that p because you don't know that it is not possible that q and not q. This wouldn't work because in fact we do know that it is not possible that q and not q.

There is another case of ineffective argument from ignorance and this is when the situation that you are supposed to ignore whether it is possible or not just doesn't make sense. It is my opinion that the notion that we are in a simulation is nonsensical.

However, irrespective of whether my opinion on this is correct or not, the fact remains that nonsensical situations are ineffective for an argument from ignorance. We need to understand what it is we are supposed to not know that this isn't the case. The reason for that is simple. If we don't understand what is the situation involved in the argument, then we won't be able to decide whether we actually don't know that it is not the case.

The issue here, as it often is, is that colloquial English is horribly ambiguous, which makes any sort of precise and rigorous discussion difficult. But with sufficient effort, it is possible to make claims precisely, and once you do that, the problem disappears.

Alice states that the sky is blue. Bob states that we live in a simulation. Let's assume for the sake of argument that Bob is correct. In that case, then the sky exists in a simulation...and the simulated sky is blue.

Consider these claims:

• P1: The sky in our reality is blue


• P2: Reality as we experience it is a simulation


• P3: There exists a sky in the world outside the simulation, and that sky is blue

Alice is claiming P1. Bob states that P2 may be true, and therefore Alice can't know P3. Moreover, Alice says she knows P1, while Bob objects that she can't prove P3. While the exact definition of what constitutes knowledge is debated ("justified true belief" is a decent approximation, even if it has some issues (Gettier 1963)), the standards for proof are higher than the standards for knowledge.

Alice and Bob aren't having the same conversation; they just think they are because they didn't properly define their terms.

Consider what the second person said:

You cannot prove that we are not in a simulation and that anything is real, hence you cannot prove that your claim was true.

This may be an example of an argument from ignorance. Here is how Wikipedia describes it:

Argument from ignorance (from Latin: argumentum ad ignorantiam), also known as appeal to ignorance (in which ignorance represents "a lack of contrary evidence"), is a fallacy in informal logic. It asserts that a proposition is true because it has not yet been proven false or a proposition is false because it has not yet been proven true.

Wikipedia further explains what is wrong with such arguments:

This represents a type of false dichotomy in that it excludes the possibility that there may have been an insufficient investigation to prove that the proposition is either true or false. It also does not allow for the possibility that the answer is unknowable, only knowable in the future, or neither completely true nor completely false. In debates, appeals to ignorance are sometimes used in an attempt to shift the burden of proof.

Although Wikipedia considers this an informal fallacy Douglas Walton provides an example where an argument from ignorance is appropriate:

There seem to be many cases where, as a presumptive guide to action, the ad ignorantiam argument appears to be quite reasonable. One cited in (Walton, 1996, p. 86) involves the use of the common rule of safety in the handling of firearms: if you do not know for sure that a weapon is unloaded,you should act in accord with the presumption that it is (or may be) loaded.In a given case, if I walk up to the firing range and pick up a pistol, the right thing to do before waving it around is to open the chamber and check to be sure that the weapon is unloaded.

Walton is referencing his book length treatment of this argumentation strategy: Walton, Douglas: 1996, Arguments from Ignorance, Penn State Press, University Park, Pennsylvania

Walton, D. The Appeal to Ignorance, or Argumentum ad Ignorantiam. Retrieved on August 14, 2018, from Douglas Walton's site at https://www.dougwalton.ca/papers%20in%20pdf/99ignorantiam.pdf

Wikipedia contributors. (2019, July 23). Argument from ignorance. In Wikipedia, The Free Encyclopedia. Retrieved 14:49, August 14, 2019, from https://en.wikipedia.org/w/index.php?title=Argument_from_ignorance&oldid=907463760