I'm not at all sure what you said there. I don't know what a "physical reference" might be... — Banno

By a physical reference I mean a physical system used in comparing a second tier reference standard to the current definition of a physical unit (e.g. metre). The physical reference for a metre is something that has changed over time.

The metre was originally defined in 1791 by the French National Assembly as one ten-millionth of the distance from the equator to the North Pole along a great circle, so the Earth's polar circumference is approximately 40000 km.

In 1799, the metre was redefined in terms of a prototype metre bar, the bar used was changed in 1889, and in 1960 the metre was redefined in terms of a certain number of wavelengths of a certain emission line of krypton-86. The current definition was adopted in 1983 and modified slightly in 2002 to clarify that the metre is a measure of proper length. From 1983 until 2019, the metre was formally defined as the length of the path travelled by light in vacuum in 1/299792458 of a second. After the 2019 redefinition of the SI base units, this definition was rephrased to include the definition of a second in terms of the caesium frequency ΔνCs. This series of amendments did not alter the size of the metre significantly – today Earth's polar circumference measures 40007.863 km, a change of 0.022% from the original value of exactly 40000 km, which also includes improvements in the accuracy of measuring the circumference.

https://en.m.wikipedia.org/wiki/Metre

...nor an "actual metre". — Banno

I wasn't suggesting that you had a concept of an "actual metre". As I said, "I assume you aren't suggesting there is such a thing as an actual metre, aside from there being such a consensus on how "metre" is defined." I suppose I was mostly concerned that people might misinterpret you saying "...no more a fact than the length of the standard metre was 1m." as suggesting there is a fact of what an actual metre is, apart from the human consensus.

Are you aware of the difference in opinion between Wittgenstein and Kripke?

A thread on its own. Or a career. — Banno

Not very aware.

I have a career very much involved with metrology (though not metres specifically). I suppose I'm inclined to get pedantic on the subject.

It would be unreasonable to conclude that Mars doesn't exist just because it takes time for the photons of light to arrive at one's eyes. — Corvus

True, the photons of light that enter my eye were caused by something that existed in the past, and just because something existed in the past doesn't mean it still doesn't exist in my present.

Whilst the Indirect Realist is more of the position that I see the photons entering my eye which I can then reason to have been caused by something in the past, the Direct Realist is more of the position that they are immediately and directly seeing the external world as it really is.

Yet how can the Direct Realist be immediately and directly seeing the external world as it really is when there is no guarantee that what they are seeing still exists?

True, the photons of light that enter my eye were caused by something that existed in the past, and just because something existed in the past doesn't mean it still doesn't exist in my present. — RussellA

This sounds like you are being pedantically sceptic here.

Yet how can the Direct Realist be immediately and directly seeing the external world as it really is when there is no guarantee that what they are seeing still exists? — RussellA

This point proves that the categorisation of indirect and direct realist is a myth. I used to think the distinctions were legitimate before, and was tending to take IDR side.

But having read some books and thinking about it, it proves that the distinction may not exist. There is just perception, and perception with reasoning. There is no such things as indirect or direct realists. Maybe there are. You see and read about them, but the discussions end up futility gaining little.

True, the photons of light that enter my eye were caused by something that existed in the past, and just because something existed in the past doesn't mean it still doesn't exist in my present.

Whilst the Indirect Realist is more of the position that I see the photons entering my eye which I can then reason to have been caused by something in the past, the Direct Realist is more of the position that they are immediately and directly seeing the external world as it really is.

Yet how can the Direct Realist be immediately and directly seeing the external world as it really is when there is no guarantee that what they are seeing still exists?

I was under the impression, perhaps mistaken, that the direct realist believes he views the external world directly, while the indirect realist views the external world via some internal or mental construction.

Your distinction seems to me to be one without a difference because photons are of the external world, and if so, one is immediately and directly perceiving the external world. And the qualifier “as it really is” doesn’t much pertain to direct realism in the same way as the phrase “as it really isn’t” might pertain to indirect realism.

And the qualifier “as it really is” doesn’t much pertain to direct realism — NOS4A2

And yet that seems to be a feature of every definition of direct realism.

So maybe wonderer1’s mention of a “connotation of animism” was quite relevant. — Jamal

Yes, somewhat, but there was still a recognition of the difference between the animate and the inanimate, and according to Aristotle the inanimate does act. To say that @fdrake's dumbbell is heavy is, for Aristotle, to say that it acts in a certain way. A star "presents itself" to the eye via light and a dumbbell "presents itself" to the hand via shape and weight. Still, animism might be a very natural setting for this idea.

Because our age is so focused on subjectivity it has become difficult to imagine a way of viewing the world which does not place subjectivity at the center. For example, to speak about things like animism or realism or projection already presupposes the centrality of subjectivity.

I’d read that Barfield essay if I could find it. — Jamal

Yeah, I see that it is still as elusive as it was years ago. It is contained in Rediscovery of Meaning, which I found in a physical library some years ago. A concise summary of the idea can be found here. Barfield is comparing an aeolian harp to a camera obscura. I should try to find the essay and revisit the idea.

And yet that seems to be a feature of every definition of direct realism.

I’d be interested to read a direct realist using such a phrase in their arguments, if you know of any quotes. I guess we can say the indirect realist believes he perceives the world as it really isn’t.

I guess we can say the indirect realist believes he perceives the world as it really isn’t. — NOS4A2

This phrasing is kind of odd, but if it works for you then that's fine.

I would say, there are features of our perceptual experience that cannot also be objective features of the the objects we perceived. Most indirect realists will accept that their perceptual experience is caused by the object, and in some important senses highly correlated to objective features of that object, but that that's nevertheless different from "the object as it really is".

Which features would those be?

The qualia of colour, for example. There's no objective reason why I apply the qualia I call blue to the wavelength range of light that I apply it to - that's a semi-arbitrary assignment, and for all I know it could be different in another person. You could have your colour wheel rotated with respect to mine.

So we would both be having very different visual experiences while looking at the same object, and neither one of us would be objectively more right or wrong than the other - are both of these different visual experiences "reality as it really is"?

The fact that we perceive colour in a "colour wheel" at all is a great example of perceptual experience containing artifacts unique to our biology that don't belong to reality-as-it-is. There's no reason why we should see a colour wheel instead of a linear colour spectrum. It's a biological accident that our eyes turn the signals from light wavelengths into a wheel rather than a linear spectrum.

For all you know our color wheels could be exactly alike, and thousands of years of evolution might have produced an anatomy very similar, with only slight degrees of variation. Nonetheless, we’d all be seeing nothing if both the objects and lights didn’t afford us the information of the outside world that it does.

:ok: :ok:

I haven't had time to come back on other replies unfortunately. Writing for school.

I agree with every word you said there

good luck with your writing

Good stuff. Then we share common grounds.

Is the variation in colors a direct perception of internal qualia, and not a direct perception of external objects, such as the light and the things it bounces off of?

idk what you mean by "direct" here. Idk what your question is asking.

Thanks for that, but I am still unclear as to what, or if, you are asking or suggesting.

Th point being made was to do with the nature of metaphysical claims - see Confirmable and influential Metaphysics; That the truth of metaphysical claims is not determined by the world around us but by the way we use them - in the same way that a bishop is determined by restricting it's movement, that the length of a metre was determined by the standard metre, and the conservation of energy is determined by invoking symmetry.

I would have thought that an Indirect Realist would also have said "I see what appears to be a bent stick". — RussellA

Which just goes to show that the debate is ill-conceived and pointless.

It just means there are no intervening factors when it comes to perceiving the rest of the world, or that perceiving the rest of the world is not indirect.

There is no such demand. To make it would be foolish as perception is inherently indirect, it necessarily involves construction of a representation. — hypericin

Direct and indirect realists can both agree that perception necessarily involves construction of a representation. They disagree over whether the construction of a representation is only the act of seeing or whether it is also the object that is seen.

Direct realists consider the construction of a representation to be what enables us to see anything. They consider the first-order construction of a representation of an object to be “seeing” a real object. Indirect realists disagree and say that the construction of a representation is not only the act of seeing, but is also the object that we see. The problem for indirect realists (from a direct realist's point of view) is that seeing a representation would require a second-order construction of a representation of a representation, and so on.

For direct realists, the construction of a representation is only the act of seeing, or the bodily function that enables us to see, which therefore allows us to see real objects.
For indirect realists, the construction of a representation is both the act of seeing and the object seen, which allows us to see... nothing other than how our visual system functions, I suppose.

The conversation between direct realism and indirect realism isn't about "demands", I don't think the word "demand" is helping with clarity here. — flannel jesus

Fair enough, it was perhaps a poor choice of word. Please see my reply to @hypericin.

Indirect realists disagree and say that the construction of a representation is not only the act of seeing, but is also the object that we see. — Luke

I would not put it this way. I don't think indirect realists abuse language the way you say they do. To them you see objects, but seeing is mediated by the indirection of representation. The only thing you directly experience (not "see") is perceptions/representations, which, while they map to objects, are themselves entirely not the objects they represent.

Whereas, to the non-naive direct realist (as I understand them), perception is the organism directly rubbing against the world. It contacts the world, and responds to it. There is no such thing as perceiving an object as it is, the concept is incoherent, and so perceptual representations are as direct as you can get. Moreover, logically you must be able to perceive things as they are, in order for there to be the possibility of perceiving things as they are not, in the case of perceptual errors.

Whether this debate has substance or not, or the two positions are equivalent, I'm not certain.

for me, the question is "is the representation -the world as it is- or does it have some big differences from the world as it is?"

And I think the answer is that it obviously is very different. The representation built by our brains to present to our conscious self is not just "reality as it really is", and so that's why I can't agree with direct realism.

Yep.

I see my hand directly when I look down, indirectly when I see its reflection in a mirror. Here I have a clear enough understanding of what it means to see my hand directly and indirectly.

But if someone says that when I look down at my hand I am seeing it indirectly, I do not have a way to make sense of what they say.

If they say I am not seeing my hand, but a "mental image of my hand" or some such, my reply is that, the "mental image", so far as it makes any sense, is me seeing my hand. — Banno

The representation built by our brains to present to our conscious self is not just "reality as it really is", and so that's why I can't agree with direct realism. — flannel jesus

But this is naive realism. Direct realists nowadays aren't so dumb as to believe this.

I would not put it this way. I don't think indirect realists abuse language the way you say they do. To them you see objects, but seeing is mediated by the indirection of representation. The only thing you directly experience (not "see") is perceptions/representations, which, while they map to objects, are themselves entirely not the objects they represent. — hypericin

I would say that "seeing objects" and being "mediated by the indirection of representation" are one and the same thing. If you eliminate the mediation (that indirect realists complain about), then you eliminate the seeing. Indirect realists desire (if not demand) a way of seeing that involves no representation, but that's not a thing. It's like a camera that can somehow take a photo without taking a photo.

Whereas, to the non-naive direct realist (as I understand them), perception is the organism directly rubbing against the world. It contacts the world, and responds to it. — hypericin

Even a cheap camera can take a photo of real objects. Our perception of the world might be different from a gazelle's or a hyena's, but we can each see if there's a lion nearby. I imagine an indirect realist would not be satisfied with the representation involved in the different visual systems of these different animals; that none of us really sees the lion as it is. It seems that no representational visual system is satisfactory. God's perhaps? Even that would be too representation-y for them, I'd imagine.

There is no such thing as perceiving an object as it is, the concept is incoherent, and so perceptual representations are as direct as you can get. — hypericin

Right. The concept of perceiving an object as it is, paradoxically, would involve no representation; no perception.

Yep.

I see my hand directly when I look down, indirectly when I see its reflection in a mirror. Here I have a clear enough understanding of what it means to see my hand directly and indirectly.

But if someone says that when I look down at my hand I am seeing it indirectly, I do not have a way to make sense of what they say.

If they say I am not seeing my hand, but a "mental image of my hand" or some such, my reply is that, the "mental image", so far as it makes any sense, is me seeing my hand. — Banno — Banno

I'm not sure that I would even describe seeing a hand in a mirror as seeing it indirectly. Or, at least, that's a different meaning of "indirect" compared to what it means in the direct/indirect realism discussion, imo. However, I fully agree with the rest.

↪Luke
for me, the question is "is the representation -the world as it is- or does it have some big differences from the world as it is?" — flannel jesus

As @hypericin notes, and I agree, I think the concept of perceiving the world as it is (in itself) is an incoherent one.

yeah, I fully agree, and that's the part of direct realism that doesn't sit with me.