How would one determine the probability of such a thing?

By considering all possible arguments one can think of, for and against the idea of an objective world, and inspecting whether the greater weight of arguments lies for or against the said hypothesis

What's an example of an alternative? The objective world is not manufactured by experiencing it.

I've always assumed that I was experiencing an objective reality, not manufacturing one. I think I have pretty good evidence that my assumption is correct.

I still wonder about what I can be sure of, though. Because I'm a fallibilist.

The question then becomes, is there an objective world to experience? Do you agree that there is evidence that an objective world is there to experience? — anonymous66

I usually side with internal realism, which accepts a causally independent world, rather than idealism proper, but I'm unsure if this is because there are good reasons to believe in such a thing or because of a hard-to-shake dogmatism.

Ok, but are you sure of fallibilism? Granted that statements and beliefs can be wrong as they are representational. But experience is presentational. What you see, hear etc under such and such conditions couldn't be anything but what you see, hear etc (despite the possibility to interpret it, i.e. form beliefs about it in various ways).

This is fallibilism as I understand it:

Fallibilism (from Medieval Latin: fallibilis, "liable to err") is the philosophical principle that human beings could be wrong about their beliefs, expectations, or their understanding of the world.

Can someone prove that that prinicple is false?

Fallibilism (from Medieval Latin: fallibilis, "liable to err") is the philosophical principle that human beings could be wrong about their beliefs, expectations, or their understanding of the world

I prefer this definition:

"Fallibilism, the recognition that there are no authoritative sources of knowledge, nor any reliable means of justifying knowledge as true or probable."

Fallibilists accept even their best and most fundamental explanations to contain misconceptions in addition to truth, and so are predisposed to try and change them for the better.

It is trivially true that beliefs or expectations could be wrong. Likewise, some beliefs or expectations could be right. Experiences, however, are facts. There is no good reason to be unsure of whether this web page exists as one's eyes are interacting with it.

What's the pretty good evidence you have?

Have you ever come across the phenomenon of an "optical illusion"?

When the scientists experienced superluminal neutrinos recently, was that a fact?

Reading, talking to people. We all appear to be experiencing the same reality.

There is no good reason to be unsure of whether this web page exists as one's eyes are interacting with it. — jkop

Sure. I don't deny that.

There's a difference between truth and the idea of truth, isn't there? You start off by speaking about what the idea of truth seems to be, yet your conclusion is regarding truth itself, and consists of conflating the two. The idea of truth vs. truth, and also seems to be vs. is. Your reasoning is invalid. — Sapientia

I'll try explain what my thoughts were and see if that helps to clarify whether what I wrote is invalid.

"I don't know what it could mean to say that truth is objective".
In other words, rocks, trees, mountains and rivers are objective, meaning that they exist, they are actualities; but, it seems incoherent to say of truth that it is an actuality in this sense.

"The idea of truth seems to be the idea of something really being the case; the idea of an objective state of affairs or actuality."
This is expressed a wee bit wrong, although I think a charitable reading should still have got the gist of it. The last sentence should have been something more like: "the idea of the obtaining of an objective state of affairs or actuality".

" So, truth is the idea of the objective, it is of the objective, but is not itself objective, it is of actuality, but is not itself actual."
Truth is propositional, or ideal, isn't it? So, when I say it is the idea of the objective, this would be equivalent to talking about the "obtaining" of the actual, or the fact that the actual is the case. Language is an imperfect medium, with its own inherent inconsistencies; the best we can do is to try to skirt around those inconsistencies in order to get a sense of just what our idea of truth really is. Truth, I would say, cannot be analyzed in terms of something more basic or primary, and because of that it cannot be precisely analyzed at all.

It's true that it is common to speak about the truth being actuality, and looked at another way this also rings true, but it is also true that there is a true distinction between truth and actuality; because actuality cannot be about the truth, whereas the truth is always about actuality. Don't be too anal(ytic) retentive or too incontinent(al) about it, I say. These are the two modern over-reactive philosophical extremes; steer a virtuous middle path. ;) :)

I love Aristotle's optimism about the truth even though I don't share it.

For the true and the approximately true are apprehended by the same faculty; it may also be noted that men have a sufficient natural instinct for what is true, and usually do arrive at the truth. Hence the man who makes a good guess at truth is likely to make a good guess at what is reputable.

...Rhetoric is useful because things that are true and things that are just have a natural tendency to prevail over their opposites, so that if the decisions of judges are not what they ought to be, the defeat must be due to the speakers themselves, and they must be blamed accordingly. — Aristotle's Rhetoric

I wish I felt this way. But I read Vance Packard's 'The hidden persuaders' at a formative age and I've never been the same since.

Sure, why? And no, they didn't experience some false behaviour of neutrinos, it was their interpretation which was false due to a screwed up cable or the like. The possibility to mess with the conditions of observation to mislead the observer is no reason to believe that all observation would be unreliable. An optical illusion wouldn't be possible without seeing light as it really is, refraction as it really is, etc.

So, "experiences are facts" but they need "interpretation"?

You claim to be able to see light "as it really is". What is it, and how do you do that?

Why would experiences "need interpretation"? Seeing light is a 'basic action' by way of which anything visible is seen, but one does not need to interpret, nor see something else, in order to see light.

Seeing light "as it really is" is to see light without an assumed intermediate representation.

I am inclined to say there are different sorts of truth, but only because the expression "sorts of truth" makes sense. People say the phrase and I understand what they mean.

In the same way "objective truth" is meaningful. I usually get the gist of what someone means when they use the term.

Merely at the level of meaning, then, yes I can go with both phrases. I don't consider them as somehow forbidden to speak of -- but I would note that it could become very easy to get tripped up on this kind of vernacular when we might ask after a more rigorous expression of truth or objectivity.

Seeing light "as it really is" is to see light without an assumed intermediate representation. — jkop

Which of course is completely impossible. You don't see light. You respond to an electrical signal transmitted from a receptor in your eye which obviously isn't light at all. If you believe that that is 'seeing light' as you describe it then a television screen sees light, an oscilloscope sees light, heck, even a loudspeaker attached to a detector 'sees' light. We do not ever see 'what is there'. We only ever see the translation made by the particular receptor and 'display' combination it affects. This should be apparent the first time you realise that everything we see that's not a light source in itself is effectively a negative, translated from the light rejected by an object, and a wholly incomplete one at that since we have no power to at all to 'see' but a tiny proportion of the wavelengths arriving.

There is a very real sense in which human vision is not seeing at all! Everything you see 'out there' is actually entirely 'in here' (he says pointing to his brain)!

With what organ do you see the alleged things inside your head, hm?

I saw the full moon this morning. It was in the external world above the holly tree. Did you see it?

I hear ya. But I think that's making use of the fact that "truth" can mean true statement.

I saw the full moon this morning. It was in the external world above the holly tree. Did you see it? — Mongrel

Well - as they say when they're fretting about an excluded middle - I did, and I didn't. :)

Which part of receptor (eye) in combination with signal interpreter (in this case the cerebrum) did I fail to clarify? You would be just as blind if the connection of two perfectly functional eyes to the brain was severed as you would if somebody glued those eyes shut.

And just as I'm talking about this, I see ...

The Evolutionary Argument Against Reality in Quanta

You don't see light. You respond to an electrical signal transmitted from a receptor in your eye which obviously isn't light at all. I — Barry Etheridge

Quite! I was hoping for at least an answer to the wave/particle question. Although that is already answered, it would be reassuring to discover what the real experience really tells us.

And just as I'm talking about this, I see ... — Barry Etheridge

I think people who claim they don't exist should be taken seriously.

Which part of receptor (eye) in combination with signal interpreter (in this case the cerebrum) did I fail to clarify? You would be just as blind if the connection of two perfectly functional eyes to the brain was severed as you would if somebody glued those eyes shut. — Barry Etheridge

Do you think that a robot, programmed with all kinds of image recognition algorithms, sees anything?

Do you think that a robot, programmed with all kinds of image recognition algorithms, sees anything? — tom

Depends what you mean by 'see', doesn't it? In so far as it receives enough information via computational analysis of the input to make informed decisions or direct action towards an object, you'd have to say yes. If seeing involves aesthetic evaluation and emotional effect then probably not.