For example, let's say that I'm teaching you the game of chess, that is, I'm explaining the rules of the game, but you are doubting everything that I tell you. Now according to you it's okay, because doubting is a relative concept, that is, one can use it any way one sees fit, but how can this be the case? Aren't there rules of correct usage, or do you apply your own rules? — Sam26

I am not following. You have a guy describing the rules of chess to you and you are doubting . . . exactly what? You say "everything he says". What does that mean?

When someone says "tomorrow it will rain" you can doubt that. It makes sense. You can say "well, maybe it won't rain". But when someone says "these are the rules of the chess" and you doubt that what does that mean? I can interpret it in a positive manner but I am not sure this is the way you are interpreting it. For example, maybe you are saying to this guy "well, these are not the standard rules of chess" where "the standard rules of chess" means "what most people understand to be the rules of chess". This makes perfect sense. You can make such objections. I don't see how such a doubt is something other than perfectly sensible. It might turn out that most people think that the rules of chess are something other than what this person is telling you the standard rules of chess are.

That's not right at all. To put in some semi-arbitrary percentages, it's certain if the probability is 100%, likely if the probability is >=75%, unlikely if the probability is <= 25%, and impossible if the probability is 0%. — Michael

Your numbers are totally arbitrary. If you use "doubt" in this way, you have no clear division as to what probability ought to be doubted, and what probability ought not be doubted. Therefore you have just deferred the doubt, such that we must now doubt whether or not to doubt any particular probability. Do we doubt a 60% probability, 80%, 90%? If we make a determination that we ought to doubt 90%, but not 91%, then we can still doubt that judgement, and also doubt the judgement of the judgement. All you have done is inverted the infinite regress of justification so that it now appears as an infinite regress of doubt. .

We often use the term "doubt" to refer to something with a low probability, not just to anything that isn't certain. If the likelihood that I will win the game is 95%, then I'm not certain that I will win, but neither am I doubtful. I'm pretty sure that I will win. — Michael

But 95% probability does not remove doubt. Nor does 99%. I've been explaining doubt as an attitude. It is dichotomize with certitude, not certainty (in the sense of "it is certain"), so let me straighten out my categories.

If, when it is 95% certain that you will win the game, you do not proceed with the attitude that it is possible for you to lose (doubt), then you probably will lose. It's like a work place accident, if your attitude is that statistics show it's highly unlikely for me to be injured on my job, therefore I do not need to be careful in my actions, then you will be the one to get hurt. So doubt is the attitude which encourages us to avoid the possibility of mistake. It is to be respectful of the possibility of mistake. Even when that possibility is very low, we must respect it, and this reflects in our actions, as an effort to avoid mistakes wherever they are apprehended as possible. Doubt must coexist with confidence, in order that we will proceed, but certitude is a type of extreme confidence, like arrogance, which negates doubt, making us lose respect for the possibility of mistake.

"Pretty sure" isn't "certain", but neither is it "doubtful". You're setting up a false dichotomy. — Michael

As I said, the dichotomy is between certitude and doubt, as these are both attitudes which negate each other. The dichotomy is not between "doubt" and "certain". "Pretty sure" is not certitude. It inspires the confidence required to proceed, while allowing the doubt which inspires the effort to avoid mistake. Certitude inspires the confidence to proceed but without any respect for the possibility of mistake. "Pretty sure" indicates some degree of doubt.

As I said, the dichotomy is between certitude and doubt — Metaphysician Undercover

And this is the dichotomy that I'm criticising. When I say that I doubt something, I'm not just saying that I don't have certitude; I'm saying that I think it unlikely.

Contrast with thinking that something is likely, which is neither certitude nor doubt.

These all mean different things:

I'm certain that I will win
I'm pretty sure that I will win
I doubt that I will win

You said the following:

There is nothing that is immune to doubt. We can doubt anything we want. And when we don't, it's merely because we decided not to do so. — Magnus Anderson

Remember, you said we can doubt anything we want, so I gave you an example of someone teaching the rules of chess, and the person to whom they are teaching the game is doubting the rules, doubting everything the teacher says. Does it make sense to doubt in this situation? One doesn't doubt simply because one wants to doubt, one doubts because there are good reasons to doubt. Think about how the word doubt is taught, doubt arises in very specific ways, you're not taught to doubt everything, and you're not taught to doubt based on a whim. All words are taught in specific ways, that is, they are taught to be used in a specific kind of language-game. So there is a kind of logic of use when it comes to word usage, one doesn't simple apply one's own rules arbitrarily.

Constitutive rules just are what a culture, a way of life, takes to be inherently given in perception, in life. Obviously this is mediated, but not totally determined by, individual cultures. Hands are the example in question. Since the hand is indispensable, in fact absolutely foundational, to all forms of human life and culture, whether prime-itive, ancient, medieval, modern, post-modern, creative or scientific; the fact that we have hands could not be more constitutive.

but it doesn't necessarily have to take the form "I believe that..." one's actions can express one's beliefs. — Sam26

Sure; but a belief does have to be such that it could be placed in the form: X believes that B.

Someone with no language can show their belief. Someone else with language can put it in the canonical form.

Jack the cat can show his belief. I put it in the canonical form.

In neither case is the belief private. It is shown. Similarly, it must be possible to format any supposedly private belief in the canonical form X believes B.

And this is the dichotomy that I'm criticising. When I say that I doubt something, I'm not just saying that I don't have certitude; I'm saying that I think it unlikely. — Michael

Oh, I see that you insist on using "doubt" differently than me. You want to restrict "doubt" such that it would only be used if you thought something unlikely. For the purpose of epistemology, I do not think that this is a good definition. I think that knowledge ought to held to a higher standard.

Remember, you said we can doubt anything we want, so I gave you an example of someone teaching the rules of chess, and the person to whom they are teaching the game is doubting the rules, doubting everything the teacher says. Does it make sense to doubt in this situation? — Sam26

It makes sense to doubt in such a situation. I gave you an example.

One doesn't doubt simply because one wants to doubt, one doubts because there are good reasons to doubt. — Sam26

Not necessarily. For example, it is possible to doubt for no reason at all.

The point isn't that you can't doubt, the point is that in some instances, like the example I gave, it makes no sense to doubt. The doubt is senseless.

I understand that. What I don't understand is this: why do you think that in the example that you gave it makes no sense to doubt?

I understand that. What I don't understand is this: why do you think that in the example that you gave it makes no sense to doubt? — Magnus Anderson

Well, if you're sitting with an expert chess player, and they're teaching you the game of chess, and you start doubting everything he's says, without good reason, what sense could we make of your doubts? It would seem that you don't have a good grasp on reality, or you just haven't learn to use the English words correctly, or you have a mental illness.

possible, but irrational.

Eventually there is a point where your doubt is pointless. It does not serve any purpose. At that point we are quite entitled to ignore your doubt.

We might not be able to convince you but we can tell you to get lost.

I am describing what is possible. I am not giving instructions on how to doubt. That's beside the point.

Well, if you're sitting with an expert chess player, and they're teaching you the game of chess, and you start doubting everything he's says, without good reason, what sense could we make of your doubts? It would seem that you don't have a good grasp on reality, or you just haven't learn to use the English words correctly, or you have a mental illness. — Sam26

You can question his expertise for a start. You can also question whether his words truly reflect his thoughts. And so on. There are many things that you can question in such a scenario. So your claim that it makes no sense to doubt in such a scenario is what truly makes no sense.

All you're doing is changing the scenario to where it makes sense to doubt. Let's say you know you're getting instruction from an expert chess player, that's a given. He then tells you that bishops move diagonally, you then tell him, you doubt that. If there are no reasons to doubt, it doesn't make sense.

Don't give me a reason to doubt, then say, look it makes sense to doubt. Of course it makes sense if you have a good reason, but that's not what you claimed. You claimed that we can doubt whenever we want. I'm saying no, doubt requires good reasons. If you don't know if the chess instructor really is an expert, then of course you can express a doubt, that's what having a good reason means.

Alright. So your point is that sometimes there are no reasons to doubt. I agree with that. However, how does that have any impact on what I am saying in this thread?

My statements are:

1) Nothing is immune to doubt
2) The logic of doubt, i.e. when we decide to doubt and when we decide not to doubt, is relative

Do you agree with the first? I guess you do.
Do you agree with the second? I guess you don't. If so, why?

@Banno's value judgments -- yes, they are value judgments -- are of no relevance. Calling certain patterns of doubting "irrational" changes nothing.

well, yes it does. Eventually the chess master will say that this student is just being obnoxious and is not worth the time. They do not want to learn how to play chess.

That's of no relevance. I want to understand how things work. I am not interested in value judgments. I don't care if you or someone else likes or dislikes this or that. If I want to understand something dislikable, such as atmospheric temperatures that are below what humans can tolerate, I am not going to be complaining about how much I dislike these things; instead, I am going to be focusing all of my attention on trying to understand how these things work.

the thing is, belief and certainty are attitudes, and hence explicitly invoke value.

So it’s not “given this evidence one does believe....”; it’s “given this evidence one ought believe...”.

My statements are:

1) Nothing is immune to doubt
2) The logic of doubt, i.e. when we decide to doubt and when we decide not to doubt, is relative
— Magnus Anderson

That's a good way of stating the issue with doubt. Because of #2, the fact that doubt is relative to the particular individual, in the particular situation, therefore #1 is true.

For every individual there are many things which are and are not subject to doubt. But these things vary from one individual to another, such that nothing is beyond doubt in relation to everyone in every situation.

There are many things which I doubt, which Banno finds unreasonable to doubt, and there are completely different things that I doubt which Sam26 finds unreasonable to doubt. And there are also things which Banno and Sam26 doubt, that I do not doubt. There is not a whole lot of consistency between one person and another with respect to what we doubt, and this is what makes it unreasonable to claim that there are some things which are beyond doubt. But of course Banno and Sam26 doubt this, just like I doubt that there is anything which is unreasonable to doubt.

Eventually there is a point where your doubt is pointless. — Banno

Or we can say, a point where one's doubt is baseless.
Doubt has to hinge on something we know. We just could not haphazardly doubt anything and everything. The foundationalist would just dismiss us as irritating. And then, of course, what would we say when someone calls our attention to the fact that doubting itself is certitude.
Certainty is indestructible.

Lemons are bitter.

If @Magnus Anderson wants to say repeatedly that they are not bitter, that tells us something about Magnus, not something about lemons.

If he insists that it is worth doubting that two and two is four, that tells us again about Magnus, not about arithmetic.

If he insists on doubting that the bishop only moves diagonally in chess, again, that is about him, not chess.

And if he insists on doubting the hand flapping before him...

If Magnus Anderson wants to say repeatedly that they are not bitter, that tells us something about Magnus, not something about lemons. — Banno

If you repeatedly say that lemons are bitter, does that tell us something about you or about lemons?

Let's say you know you're getting instruction from an expert chess player, that's a given. He then tells you that bishops move diagonally, you then tell him, you doubt that. If there are no reasons to doubt, it doesn't make sense. — Sam26

What if he tells me that bishops move horizontally and vertically. Does it make sense to doubt him?

Constitutive rules just are what a culture, a way of life, takes to be inherently given in perception, in life. Obviously this is mediated, but not totally determined by, individual cultures. Hands are the example in question. Since the hand is indispensable, in fact absolutely foundational, to all forms of human life and culture, whether prime-itive, ancient, medieval, modern, post-modern, creative or scientific; the fact that we have hands could not be more constitutive. — Janus

I assumed you were working with the definition of 'Constitutive Rule' given earlier in the thread, according to which a Constitutive Rule is an ostensive definition of a word. But here you say that a constitutive rule is 'what a culture takes to be inherently given in perception'. Is it what is actually given in perception, or merely what some people 'take' to be given?

Best,
PA

If he insists that it is worth doubting that two and two is four, that tells us again about Magnus, not about arithmetic. — Banno

What does it tell you about him?

Best,
PA

What value is Epistemology in a post-Cartesian world?

Lemons might not be bitter. There is a possibility. It might be the case that our perception is altered by hidden forces (e.g. aliens.) Each time we taste a lemon aliens make sure we don't perceive its real taste.

Lemons might not be bitter. There is a possibility. It might be the case that our perception is altered by hidden forces (e.g. aliens.) Each time we taste a lemon aliens make sure we don't perceive its real taste. — Magnus Anderson

Surely it's "real" taste (although what purpose does the term "real" serve here?) just is whatever it tastes like to us?

It doesn't make much sense to me to say that we taste it as bitter but it's "really" sweet.

What if he tells me that bishops move horizontally and vertically. Does it make sense to doubt him? — Michael

Actually no, if you believe he is an expert, and all the information you have about him points to him as an expert, you would still have no reason to doubt him. Especially if you know nothing about chess. Later as you learn more you might think it weird that a chess expert would have told you such a thing. Or later you may find out that he is a practical joker, then you may reason to doubt what he says.

Actually no, if you believe he is an expert, and all the information you have about him points to him as an expert, you would still have no reason to doubt him. — Sam26

So the unreasonableness of doubt depends on there being reasonable evidence in favour (in this case, reasonable evidence that he's an expert)?