Note: This post is a follow-up to the chapters in my 2018 book about visual experiences of spatially distant things, things that are at some depth in one’s visual experience.
It is common to talk about the direction of vision, visual direction, or line of sight, and in general where things are located visually. It seems right to say that things seem to be located in a particular visual way to the seeing subject. In addition, there is a particular direction to this appearance, in that some things can be said to be visually off to the side or straight in front of the seeing subject. However, I have problems with deciding what actual or real direction should be used to evaluate this visual appearance. A consequence of these problems is I can only find bad reasons to hold that a visual appearance of direction is inaccurate.
This is a discussion about vision and space, not vision and time. But I think that what I’m going to say here relates to both. The issues for vision and space are very similar to issues for vision and time. The difference is that, for many theorists, time has a direction in a way that space does not.
Accuracy-Conditions of the Visual Appearance of Spatial Direction
When I stand outside on a clear night with a full moon, the full moon will seem to be a certain distance and in a certain direction from me. This is a particularly visual experience: I (at least seem to) see the moon; I don’t (at least seem to) hear it, smell it, or touch it. One might then ask: is the appearance of the moon’s direction and distance accurate? I don’t like my answer but I don’t know what to do about it. My answer is: except in one possible special way, it is never inaccurate; it is always accurate.
The possible special way is this: if the appearance of the moon’s direction and distance is of it as absolute, then it is not accurate. I assume that apparent direction and distance is highly unlikely to correspond to an actual spatially absolute direction and distance. I do not think that there is absolute direction and distance. Furthermore, if there is an absolute direction and distance, then it would be a matter of chance that appearances correspond to it.
However, I also think that this isn’t clearly how we see the direction and distance of things. If we do, then we can say that this is an erroneous experience of the absoluteness of these spatial properties. For now, whether we have it or not, I’ll put that particular possible experience aside.
This leaves the question I’m interested in: under what conditions is the visual appearance of distance and direction accurate? I am interested in this question because, so far as I can tell, the answer seems to be one of the following:
(a) Visual appearance of direction is inaccurate when it fails to correspond to a relative direction in space.
(b) Visual appearance of direction is neither accurate or inaccurate because there is no fact of the matter about direction. ‘Direction’ is arbitrary.
(c) Visual appearance of (spatial) direction is always accurate because the definition or grounding of direction comes from the appearances, and nowhere else.
For those who want to say that the direction in which something seems is mistaken, (a) seems best. As there is no absolute direction in space, any attempt to define direction is relative. As with distance or speed, no spatial entity is privileged with respect to spatial direction. It is relative to some points that anything is ‘far away’ or ‘moving fast’. It is also relative to some points that anything is ‘in front of’, ‘behind’, ‘above’, ‘below’, ‘to the left of’, and so on.
So, the appearances can be inaccurate with respect to relative direction. Yet, which relative direction? Determining that is problematic.
In general, appearances can be used to measure something. Appearances can play an epistemological role, where a theory of the world is evaluated by how closely it corresponds to appearances. In that case, appearance is somewhat like a measuring device, such as a metre stick. If we treat appearances that way here, then (c) is to be preferred: one evaluates the direction of something with respect to visual appearances.
However, here, we are asking about the appearances – about the accuracy of the measuring device itself. Ideally, one does not pick the thing being judged to evaluate it. That makes the accuracy trivial, like measuring a metre stick with itself.
So, what do we do? First, maybe we must bite the bullet here and use appearances, i.e., (c). Whether we like it or not, there is no better way of judging actual visual direction. But many may think otherwise: the other options surely can do something here. Either it is (b), there is a relative visual direction independent of appearances or it is (a), there is some absolute visual direction independent of appearances.
Honestly, I think it’s a toss-up between (b) and (c). What weighs the odds in favour of one or the other is whether you want to treat appearances seriously. If you are happy to throw them out (e.g., you hold that appearances never define or ground anything), then go for (b). If you are happy to have them play an epistemological role, go for (c).
However, note that (b) doesn’t provide a direction to evaluate visual appearances against. Instead, it is the position that there is no fact of the matter about a direction. The visual appearance is mistaken insofar as it seems to favour one direction over another. If you say that something seems to be in front of you, or to the side, your mistake is to hold that this could ever be something non-arbitrary – any kind of fact – one way or the other.
So, I think it can be (b) or (c), and I prefer (c) but can say little to dissuade someone convinced by the arbitrariness in (b).
However, I think my suggestion that only (b) or (c) are available should look obviously wrong to at least some readers. One should take (a) — judgement by relative direction — seriously.
For example, surely the very definition of mirages requires accuracy with respect to a relative direction [next section].
Image on by Brahan Milla on Unsplash.
Mirages, as commonly described, are visual experiences where there seems to be something at a particular location in space which is not at that particular location in space. In the most obvious examples, the variation of appearance and reality is typically described as being visually inverted: that what visually seems to be facing one way is actually facing another.
So, in an otherwise empty desert, I see in a small region of the sky, hanging above the horizon in front of me, a street scene — one inverted so that the street occupants’ heads lie below their feet. This is clearly not how they are: they are not walking upside down in the sky. This is an inaccurate visual appearance.
That is a fairly straightforward way of describing the mirage. I imagine it would be risible for many to suggest otherwise. I’m going to suggest otherwise.
The reason I’m going to do that is the account of mirages is more complicated than that it ‘appears upside down and is not upside down’. Once the complications are included, I’m not sure that it’s right to say that things are not how they seem visually. I think that it’s better to say: things are how they visually seem but they do not match expectations of how I might interact with them beyond seeing them. Yet these latter expectations are based on my ignorance of how what I see and what I can touch may interact. This is a multi-sensory error, or an error of multisensory integration, but not of my visual experience itself.
Some examples of mirages:
- http://mintaka.sdsu.edu/GF/mirages/mirintro.html (albeit in considerations of ‘green flashes’ — however, I found this site a great start for research into mirages).
- Physics.org discussion on mirages (with explanation and video example)
(For more on this section, see my 2018.)
If I believe in elves that can be seen, then I do not hold that the visual appearance of elves is necessarily either an illusion or an hallucination. If I don’t believe in the moon, then I hold that the visual appearance of the moon is necessarily either an illusion (the moon is really something else with wrong apparent properties) or an hallucination (there is nothing there). What you believe is real partly determines your beliefs that how things seem is how things are, i.e., is accurate.
When some experience is an illusion or hallucination, it is in error in some way. As I’ve argued in an earlier post, how it is in error depends (at least in part) on how things appear (a phenomenological condition) and how things are really (a metaphysical condition). What one holds about the latter condition (at least) is theory-dependent. Thus, that there is an error — and what kind — is also theory-dependent.
The error can be different according to different theories even if: (a) everyone agrees as to what is really going on; they need only disagree about what appears to be going on; (b) everyone agrees as to what seems to be going on; they can disagree about what is really going on.
From this, I think that what is erroneous can depend on what one holds to be real about the senses themselves — and the properties we ascribe to them.
Turning this to errors in the direction of gaze (or visual direction), I think that there are three factors to consider:
(a) The definition of the direction of gaze
(b) The possibility of experiential error of direction which it neither illusion nor hallucination (anosognosia).
(c) The possibility of an experiential error of direction at all
Here is my reasoning for taking (c) seriously.
First, as argued elsewhere on the site, I don’t presume the universality of illusory counterparts. Just because something can be apparent doesn’t mean that it can actually be illusory. In the widest set of possible worlds, yes – it’s possible that what’s apparent is merely illusory — but it is an open question with respect to the actual world.
I think that the greater share of claims to error of direction are discrepancies between
(i) The apparent direction of something and
(ii) Its direction relative to a Earth-derived geometric system idealised as a sphere.
However, I also think that there is no particular reason to evaluate the accuracy of (i) by (ii). If one is to evaluate it by anything, it should be
(iii) A direction relative the path along which light travels from the source to the eye.
However, (i) is always accurate when evaluated with respect to (iii) light. That is, if something appears to be straight in front of you in mirages, loomings, or other strange visual phenomena, this is not, strictly speaking, erroneous. By the standard of the path of light itself, it is straight in front of you. This is the case if you choose the path of light from the source to your eye, the very thing that allows you to see the source. If you choose that path, then the source is straight in front of you and even orientated as it appears to be; that apparent direction and orientation is not mistaken.
(You might choose some other path of light to evaluate it, and judge it wrong. Fine — but why? One path of light is as good as another. If you are arbitrarily doing so, then the error here is at best in the absoluteness of apparent direction and orientation (and distance — but I’m ignoring that in this post)).
I think that will sound very wrong to many readers. However, I think, when it comes to considering the alternatives — the body, the world, the head etc. etc. — light is still the better option. All other options lead to cases of error that are intuitively not error. This option leads to cases of veridicality that are intuitively error. Since these cases are also cases of perceptually apparent veridicality (simply by being perceptually apparent) then we have a clash between (a) appearances of veridicality and (b) intuitions of error. In such a clash, where neither side is incoherent, I pick (a) every time.
Let’s look at some alternative ways of picking out the correct direction to judge experienced direction.