If you think you might know things that are not true, then you are using an... eccentric...notion of "know".

Is it begging the question? No. The proof is not a deduction, it is a definition.

The proof is not a deduction, it is a definition. — Banno

In other words there's no reason why one cannot know a falsehood. I can, if I wish to, define knowing such that it's not an issue to know a falsehood.

That said, I believe there's a very good reason why philosophers decided on a definition that makes it impossible to know an untruth. I'd like to know more about that, thanks.

Consider the situation where I believe a lie (falsehood) e.g. that the earth is flat. Until I'm disabused of this erroneous view, I'll maintain, till I'm proved wrong and assuming I'm not a stubborn fool, that I know the shape of the earth - flat. This aspect of knowing is lost in a definition that precludes knowing a falsehood. Now. I'm not sure but do you suppose anyone would describe this view of know/knowing as impoverished and utterly fails to capture the nuances and subtleties of know/knowing? I, of course, defer to the better judgment of experienced and knowledgeable philosophers but I'm curious. Why can't we know a falsehood?

In other words there's no reason why one cannot know a falsehood. — TheMadFool

Hence,

Now that is a neat, reasonably coherent way to think about these terms. You are not obligated to think in this way, of course - you will do as you will. But if you keep this hierarchy in mind you will be able to follow the philosophical discussions around these issues with some clarity, and event to critique a few odd alternatives. — Banno

If you claim to know a falsehood it is because you are not using "know" in the way specified. So you are on your own. See how you get on.

I, of course, defer to the better judgment of experienced and knowledgeable philosophers but I'm curious. Why can't we know a falsehood? — TheMadFool

If it is a falsehood is it then not the case that we think we 'know' X is the case, when it isn't? My understanding is that we can only know true things. In more colloquial terms we tend to use the word 'know' to express a level of confidence. Or are you asking is it possible for us to know that something is untrue? For instance, I know that the English queen is not 40 years-old.

What Banno said.

I'd also add that it makes sense for people to attempt to understand what someone else means rather than categorically say they are 'wrong' when it comes to judgements like this - which are often personal.

I've had an issue with people telling me that I was using the term 'belief' in the wrong way and that there was one common meaning. They fell silent after I quoted several different definitions used by philosophers over the ages.

Another loaded term is 'faith'. All I ask is that people try and ne generous in their interpretations and perhaps ask for clarity rather if they believe something sounds stupid/wrong/insane.

:up:

:smirk:
:roll:

:chin:

Belief, n. – An assent to an expression, narrative, idea, assumption, proposal, interpretation, proposition, commitment.

Whether or not assent is warranted (foundherently, inferentially and/or experientially) seems to me the significant question.

It's a curious word. In other languages, there are no good translations as it is almost always attached to religious aspects of the world. At least in Spanish, this is the case and a few others.

For instance, you can say you believe in angels or God, but if you literally say, I believe the ocean is blue, something is off because belief doesn't enter into it. You understand the ocean is blue, you see it. It's not an issue of belief.

This might be one of those words that gets you stuck in a fly bottle.

Or are you asking is it possible for us to know that something is untrue? For instance, I know that the English queen is not 40 years-old. — Tom Storm

Negative truth (knowledge of the false) is equally valid to positive truth (knowledge of the truth).

I believe the ocean is blue, something is off because belief doesn't enter into it. You understand the ocean is blue, you see it. It's not an issue of belief. — Manuel

Not necessarily. If philosophy has discovered anything about epistemology, it is that the bedrock of all understanding is unverifiable belief.

Even in the case of the ocean's blue, there is a belief overshadowing the understanding that the ocean has a definite color. And, there is nothing to prevent us from understanding that the ocean is some other color, or no color at all.

However, there is one thing we can understand with absolute certainty, that we agree the ocean appears to be colored blue at certain times. Then again, this presupposes that solipsism isn't true, and you are indeed an autonomous subject - just another belief.

In other words there's no reason why one cannot know a falsehood.
— TheMadFool
Hence,
Now that is a neat, reasonably coherent way to think about these terms. You are not obligated to think in this way, of course - you will do as you will. But if you keep this hierarchy in mind you will be able to follow the philosophical discussions around these issues with some clarity, and event to critique a few odd alternatives.
— Banno
If you claim to know a falsehood it is because you are not using "know" in the way specified. So you are on your own. See how you get on — Banno

However, isn't such a position - working with a seemingly unjustified, arbitrary definition of knowledge - self-refuting? First, the claim is give credence only to justified propositions (definition of knowing) and second, with the same breath, to declare that the way knowing is defined is arbitrary.

Also, do you mind taking a look at the following attempt at an analysis of the situation?

Or are you asking is it possible for us to know that something is untrue? — Tom Storm

To the both of you

If the claim is that we can know a falsehood it simply means that falsehood(s) count(s) as knowledge.

In line with the OP's main thrust, let's examine beliefs. I say "I believe P" where P is a proposition. P needn't be true, it can be false. Belief is a choice it seems - I can, for instance, opt to believe P. When I choose to believe P, I assume P is true whether P is actually true or not. In other words, for me, P counts as knowledge i.e. I can, in a sense say, I know P. Am I, after all, not assuming P is true. Yet, P could be actually false.

Here, we have the situation where I know P but P could be false. In other words the following hold:

1. I know P, P is true. [Usual deal.]

OR

2. I know P (P assumed true), P is (actually) false. [We can know a falsehood.]

:eyes: "To know" =/= knowledge.

"To know" =/= knowledge. — 180 Proof

That's interesting. How? Why?

Predicate =/= noun, no?

Predicate =/= noun, no? — 180 Proof

I know the earth is a sphere = I have knowledge that the earth is a sphere.

:chin:

It is possible – in more cases than not likely – to be wrong about 'knowing'.

ITs a simple acknowledgment. True or not true is just an evaluation term that can only be applied on statements that are in agreement or not with current known facts.

It is possible – in more cases than not likely – to be wrong about 'knowing'. — 180 Proof

Yes, that's what my post draws attention to:

E = The earth is flat (actually false)

1. I believe E

2. If I believe E, E assumed true

3. If E assumed true, it operates in the same way as R = the earth is spherical, R actually true. In a sense then, I know E.

4. I know E (E assumed true) BUT E actually false.

5. We can know a falsehood.

-"You had said believe "in". I'll take it that was a mistake."
-Why? "Believe in" doesn't change the fact that we can accept claims either on good or bad evidence.


"If you want to choose to discuss the sense of "believing" as in accepting, that's fine,"
-You can NOT say that I believe a statement without accepting it!

but it is not the only sense of belief. And we also say "I believe you", that is: accepting what they say without evidence, on faith, as in trusting the person enough not to question the claim (their authority, our relationship, etc.)
-Again as you sad, "Accepting what they say" You can believe someone either on faith or as a true authority or because you already know something but you were not sure.

This changes nothing on how we believe/accept. Either our belief is justified (based on knowledge and evidence) or it isn't (blind faith or fallacious reasoning).


-" Again, if you want to limit things to make it easy, that's fine, but it doesn't make it a complete picture."
-No, I am not limiting anything. This is how things are by default. Humans believe/accept claims rationally or irrationally. Either they have access to objective evidence or they don't.Even when they believe an other individual, in reality they believe/accept what they it says.

To know a falsehood =/= "false knowledge". To know a falsehood = illusion of knowledge (i.e. delusion).

To know a falsehood =/= "false knowledge". To know a falsehood = illusion of knowledge (i.e. delusion). — 180 Proof

That's right but consider how knowledge is, ultimately, an assumption just like a belief. There are a lot of presuppositions (e.g. Agrippa's trilemma) - knowledge is a house built on sand. Given this is so, what's the difference between someone who claims fae believes Santa exists and another person who says fae knows Santa doesn't exist. This is not a type distinction, rather it's a question of degree (how many assumptions are made instead of whether assumptions are made at all). Thus, the person who states that fae knows Santa doesn't exist is in the same flimsy boat being rocked about, dangerously so, in rough seas as it were, as the person who avers that fae believes Santa exists but...there's a difference, fae is at a safer distance from the gunwale.

In short, knowledge, true knowledge is an illusion; To put it in different words, I know P (a proposition assumed to be true or itself based on other unfounded assumptions) but P can be false.

That's right but consider how knowledge is, ultimately, an assumption just like a belief. — TheMadFool

Stop. :shade: You're just abusing words again because you can. :point:

In short, knowledge, true knowledge is an illusion ...

So ... for instance, 'the gravitational constant' or 'both your parents were born before you were born' are "illusions"? You're talking out of your bunghole again, Fool.

In short, knowledge, true knowledge is an illusion; To put it in different words, I know P (a proposition assumed to be true or itself based on other unfounded assumptions) but P can be false. — TheMadFool

I kind of get what you are saying. I generally take the view that absolute certainty may not be possible - that aside can't we apportion confidence about the truth of a proposition based on the evidence?

All justified-true-belief-web-of-fraught-epistemologies-and infinite-regress aside - I would argue that there are some things we can say are facts (as far as it goes) and we can therefore say that to understand them is have knowledge. Taking this approach may not satisfy your absolute criteria but it does allow us to manipulate our environment rather effectively and survive (and fuck the planet up, but that's another story).

That's right but consider how knowledge is, ultimately, an assumption just like a belief.
— TheMadFool
Stop. :shade: You're just abusing words again because you can. :point:

In short, knowledge, true knowledge is an illusion ...
So ... for instance, 'the gravitational constant' or 'both your parents were born before you were born' are "illusions"? You're talking out of your bunghole again, Fool — 180 Proof

Imagine a person X.

1. X believe God exists. Insofar as X is concerned that God exists is true. X has no proof/evidence. God exists, assumed true by X though God exists could be factually false.

2. X knows the earth is round. The earth is round is factually true and X believes the earth is round.

In 1, the assumption made is explicit and clear. So far so good. In 2, however, one thinks no assumptions have been made but that's incorrect. Observe that between 1 and 2 the difference is that in the former the proposition in question, here God exists, can be factually false but in the latter, the proposition, viz. the earth is round, is factually true.

How does one know whether a proposition is factually true?

Justification?

What about the skeptic Agrippa's trilemma (Münchhausen trilemma)?

There really is no difference between assuming God exists (X believes God exists) and using a necessarily flawed system (arguments) to "prove" the earth is round (X knows the earth is round), is there? What's the difference between having no hammer and having a broken hammer?

Knowledge is a subset of belief. — Nickolasgaspar

It is not that simple. There are different type of knowledge and belief.

Yes. Technically we can agree that we take it to the case that the ocean appears blue to us under certain conditions - not at night, for instance.

I only caution against succumbing to skepticism or skeptical arguments too frequently. Skepticism cannot be refuted. It need be acknowledged and moved on from, otherwise we will have to seriously entertain solipsism or other fruitless avenues, such as thinking that every instance of perception, we may be misperceiving everything.

We wouldn't move our fingers, much less our legs, if such were the case.

It would be better to rely on using belief too much (not never), due to its religious connotations.

-"It is not that simple. There are different type of knowledge and belief. "
-How is this statement relevant? Knowledge is just one reason why people accept a claim.
Btw there is one standard for identifying a claim as knowledge but many ways to produce knowledge claims.

so you have a knowledge based belief in the claim" the earth is a sphere.

:roll:

What's the difference between having no hammer and having a broken hammer?

Same as the difference between having no car and having a car with an empty fuel tank ... having no body and having a dead body ... etc.

How does one know whether a proposition is factually true?

Equivocating "know" again. Just look: It's raining iff it's raining. Also, sound inferential arguments.

Justification?

Foundherentism (S. Haack) works for me.

"In short, knowledge, true knowledge is an illusion;"
-No it isn't. Knowledge is a claim that is in agreement with current available facts and has an instrumental value.
The problem with most positions in this thread is with people's obsession with "absolute" concepts.
We need to use a concept based on its real life use.
Since a knowledge claim is based on our current available facts, this means that new facts in the future might change the knowledge value of that same claim!

Again we need to understand that our concepts SHOULD describe the value of our claims (fact, knowledge, true) within our current limitations as empirical agents and our methods of investigation.
We should avoid contaminating our definitions with Absolute concepts.
If a claim conveys info with epistemic connectedness, instrumental value and in agreement with what we observe in nature...that is by definition Knowledge tentative in nature like all our claims.

I thank you and others for replying. I think that the 'personal meanings' aspect is an important area of questioning beliefs. There is a major difference between the personal aspects and establishing of socially constructed ones. It ranges from the way people develop ideas throughout life, ranging from personal autobiographical narratives to depictions of the world.

Children may be encouraged to think in terms of stories, including belief in Father Christmas and as they get a bit older such beliefs are seen as childhood fantasies. The examination of statements in the light of established knowledge within the cultural context of accepted beliefs. There is a certain amount of negotiation because some aspects of belief are based on subjective values, such as political beliefs, but it would seem problematic if a person held onto beliefs without a social context, and there are likely to be dialogues and debates about certain areas of belief within any given culture, but if someone held on to private subjective meanings without reference to others' understanding it would be a private world of fantasy and potential delusion.