Maverick Philosopher

Buckner Clarifies his Terminology

Terminological fluidity is one of the banes of philosophy. What follows is an admirable exercise in terminological fixation by the Worthy Opponent.  My comments are in blue.

I have been discussing toothbrushes [mirror images] with David but it’s clear we are being held back by semantics. I am not clear what we respectively mean by “reflection” or “appearance”, or of the green colour of these things. So I will try to set out what I mean or understand by the different terms.

“Phenomenal green”, “green as we see it”, “green as it appears to us”, also David’s “sensation of green” I think all mean the same thing, namely what I mean by green(ness), but let me explain what I understand by “green”.

BV: So far, so good.

1) Greenness is a visible quality of certain objects such as leaves, avocados, algae, brussel sprouts, [some] toothbrushes etc.

BV: The point needs to be put more precisely. Green (greenness) is a determinable with a range of corresponding  determinates.  (See here for the distinction.) The latter are the specific shades of green. The determinable green is arguably not a visible quality; only the lowest determinates are, the infima species. 

2) It is extended. I mean that a green patch is composed of green patches, which are in turn composed of further green patches ad infinitum. i.e. The greenness is continuous, or consists of a set of green points.

BV: This is not quite right either. Yes, a visible green patch can be subdivided, but not to infinity, for soon enough we arrive at sub-patches that cannot be seen, and this long before we get to points. A point is dimensionless: it has a location but no extension. And surely it is true that no color-determinate is visible if unextended.

3) Only a surface, i.e. a two dimensional thing can be green. However the surface is extended in 3D space, because each point can be a different distance from me.

BV: This sounds right to me. Visible green is given only two-dimensionally, even if the 'green' thing in the external world is 'green' all the way through.

4) The green quality is mind-independent, for the following reasons. (i) It exists outside me, (ii) it is a quality of the object which is green, and not a quality of me. (iii) I can no longer see it when I shut my eyes, but it is still there.

BV: Here is where the going gets tough.  If 'exists outside me' just means 'mind-independent,' then the first reason begs the question, or is circular. If, however, 'exists outside me' means 'appears outside me,' then the visible need not be mind-independent. 

As for (ii), what is the object? 'Object' is notoriously ambiguous. The thing in the external world? But then it hasn't been shown that the visible quality is a property of the object. It might just be a property of the phenomenon in Kant's sense which, though empirically real, is transcendentally ideal.

As for (iii),  if the visible quality is still there when I close my eyes, then it would have to be part of the thing itself in the external world, right? But that seems to comport none too well with the visible quality's being a phenomenal item.

5) It is inert, namely unlike heat it has no causal power to affect my senses.

BV: Seem right.  The seen green has no causal power. But how can  the visible two-dimensional phenomenal quality be both causally inert, and yet still be there when I close my eyes, given that the latter implies that the quality is part and parcel of the thing itself in the external world?  

Unlike heat? But surely there is phenomenal heat in contradistinction to heat-scientifically-understood. The felt heat of the hot coffee when I take a sip is not the same as the mean molecular kinetic energy of the coffee-water molecules. 

6) Thus it is not equivalent to reflectance properties of leaves or algae, which are powers to affect my senses, as far as we know, but greenness is an inert, non-causal quality. The leaf just is green.

BV: Yes.  The reflectance properties are dispositional properties, but there is nothing dispositional about the seen green, the phenomenal sense quality (sensory quale).  It is wholly occurrent or actual. 

7) It follows that greenness cannot be a reflectance property of green objects, although there may be some unknown causal connection between the property and the quality.

BV: Seems so.  Seen green cannot be a reflectance property of 'green' things themselves in the external world, things we call 'green' because they have the power to cause in us sensory qualia that are phenomenally green.

If, as science suggests, the green quality ‘out there’ is caused by neural processes, the greenness of “green” objects is an illusion, for it cannot be a quality of the green object. The causation cannot work in reverse. There is no way that a neural process in the brain can change or affect the quality of any object outside the brain.

BV: So when I am outside looking at my green palo verde tree in the backyard I am under an illusion because the tree in nature (in the external world) cannot be phenomenally green: that visible quality cannot be a property of the tree itself. It is conjured up in my brain by neural processes.

Is there not something dubious in the view that our direct sensory perception (in optimal conditions of lighting, etc.) of things like trees is illusory? If the seen green is illusory, then so is the smelt scent of the blossoms (The Sonoran spring is in full swing.)  And so on for all the other so-called secondary qualities/properties.  Can we keep the illusoriness from spreading to the primary qualities?

Perception: An Inconsistent Triad

London Ed writes,

I am making great progress on the perception book. I have borrowed your idea of an aporia, which I use to illustrate the central problem of perception:

(1) Transparency: This is the surface of my desk.

(2) Continuity: When I shut my eyes, the surface of my desk does not cease to exist

(3) Discontinuity: When I shut my eyes, this ceases to exist

Here is how I 'see' it.  The problem concerns the nature and status of the referent of the demonstrative pronoun 'this' when uttered by a person as he looks at a physical object such as a desk and says, 'This is the surface of my desk.'  To what, exactly, does 'this' refer? There are two main possibilities.  Roughly, either 'this' refers to something physical that exists in itself or it refers to something non-physical or mental that does not exist in itself.

P1. The referent of the pronoun is a proper physical  part of a physical thing that exists whether or not any person is looking at it. (Note that if the thing exists whether or not perceived, then so do its parts.)

P2. The referent of the pronoun is not a physical part of the desk but an item that exists only as a correlate of the act of visual awareness of the person who is looking at the desk at a given time.  This correlate is an epistemic intermediary that has (or encodes) all and only the properties of the desk the person has before his mind at the time of his perceiving.  

On (P1), the solution to the aporetic triad  is by rejecting (3) while accepting (1) and (2). On (P2), the solution is by rejecting (2) while accepting (1) and (3)

I assume that Ed will plump for (P1).  That makes Ed a kind of direct realist. The other type of view can be developed in a realist way as a type of indirect realism or in an idealist way. But no more about that for now.

Well, why not be a direct realist?  Are there any considerations that speak against it?

Philosophically Salient Senses of 'See'

This entry is relevant to my ongoing discussion with Dr. Buckner.

It is plain that 'sees' has many senses in English.  Of these many senses, some are philosophically salient.  Of the philosophical salient senses, two are paramount.  Call the one 'existence-entailing.'  (EE) Call the other 'existence-neutral.' (EN)  On the one, 'sees' is a so-called verb of success.  On the other, it isn't, which not to say that it is a 'verb of failure.'  

EE:  Necessarily, if subject S sees x, then x exists.

EN:  Possibly, subject S sees x, but it is not the case that x exists.

Now one question is whether both senses of 'see' can be found in ordinary English.  The answer is yes.  "I know that feral cat still exists; I just now saw him" illustrates the first.  "You look like you've just seen a ghost"  illustrates the second.  If I know that the feral cat exists on the basis of seeing him, then 'sees' (or a cognate thereof) is being used in the (EE) sense as a 'verb of success.'  If ghosts do not exist, as I am assuming, then one who sees a ghost literally sees something that does not exist.  We call this second sense of 'sees' the phenomenological sense.  

So far, I don't think I've said anything controversial.  I have simply pointed out two different senses and thus two different uses of 'sees' in ordinary, non-philosophical English.

We advance to a philosophical question, and embroil ourselves in controversy, when we ask whether, corresponding to the existence-neutral sense of 'sees,' there is a type of seeing, a type of seeing that does not entail the existence of the object seen.  One might grant that there is a legitimate use of 'sees' (or a cognate thereof) in English according to which what is seen does not exist without granting that in reality there is a type of seeing that is the seeing of the nonexistent.

One might insist that all seeing is the seeing of what exists, and that one cannot literally see what does not exist.  So, assuming that there are no ghosts, one cannot see a ghost.  As Joe Biden might say, "Come on man, you can't see what ain't there!"

But suppose a sincere, frightened person reports that she has seen a ghost of such-and-such a ghastly description.  Because of the behavioral evidence, you cannot reasonably deny that the person has had an  experience, and indeed an object-directed (intentional) experience.  You cannot deny, given her fear-indicating behavior, verbal and non-verbal, that she had a visual experience as of  something ghastly. You cannot reasonably say, "Because there are no ghosts, your experience had no object."  For it did have an object, indeed a material (albeit nonexistent) object having various ghastly properties. After all, she saw something, not nothing. Not only that, she saw something quite definite with definite properties.  She didn't see Casper the Friendly Ghost but a ghastly ghost.

You might object, "No, she merely thought she saw something." But there was no thinking or doubting or considering going on; she saw something and it scared the crap out of her.

This example suggests that we sometimes literally see what does not exist, and that seeing therefore does not entail the existence of that which is seen.  If this is right, then the epistemologically primary sense of 'see' is given by (EN) supra.  If so, then problems arise for realism about the external world. For example, how do I know that the tree I see in good light (etc.) exists in itself whether or not I or anyone see it? 

Henessey's response:  "I grant the reality of her experience, with the reservation that it was not an experience based in vision, but one with a basis in imagination, imagination as distinguished from vision."  The point, I take it, is that what we have in my example of a person claiming to see a ghost is not a genuine case of seeing, of visual perception, but a case of imagining.  The terrified person imagined a ghost; she did not see one.

I think Hennessey's response gets the phenomenology wrong.  Imagination and perception are phenomenologically different.  For one thing, what we imagine is up to us: we are free to imagine almost anything we want; what we perceive, however, is not up to us.  When Ebeneezer Scrooge saw the ghost of Marley, he tried to dismiss the apparition as "a bit of bad beef, a blot of mustard, a fragment of an underdone potato," but he found he could not.  Marley: "Do you believe in me or not?"  Scrooge: "I do, I must!"  This exchange brings out nicely what C. S. Peirce called the compulsive character of perception.  Imagination is not like this at all.  Whether or not Scrooge saw Marley, he did not imagine him for the reason that the object of his experience was not under the control of his will.

The fact that what one imagines does not exist is not a good reason to to assimilate perception of what may or may not exist to imagination.

Second, if a subject imagines x, then it follows that x does not exist.  Everything imagined is nonexistent.  But it is not the case that if a subject perceives x, then x does not exist.  Perception either entails the existence of the object perceived, or is consistent with both the existence and the nonexistence of the object perceived.

Third,  one knows the identity of an object of imagination simply by willing the object in question.  The subject creates the identity so that there can be no question of re-identifying or re-cognizing an object of imagination.  But perception is not like this at all.  In perception there is re-identification and recognition. Scrooge did not imagine Marley's ghost for the reason that he was able to identify and re-identify the ghost as it changed positions in Scrooge's chamber.  So even if you balk at admitting that Scrooge saw Marley's ghost, you ought to admit that he wasn't imaging him.

I conclude that Hennessey has not refuted my example. To see a ghost is not to imagine a ghost, even if there aren't any.  Besides, one can imagine a ghost without having the experience that one reports when one sincerely states that one has seen a ghost.  Whether or not this experience is perception, it surely is not imagination.

But I admit that this is a very murky topic! 

Notes on Idealism, Realism, Frege, and Prichard

Ed Buckner sent me a pdf the first couple pages of which I reproduce below. Bibliographical data here. Emphases added. My commentary is in blue. 

...........................................

Twentieth Century Oxford Realism

Mark Eli Kalderon and Charles Travis

1 Introduction

This is a story of roughly a century of Oxford philosophy told by two outsiders.
Neither of us has ever either studied or taught there. Nor are we specially privy to
some oral tradition. Our story is based on texts. It is, moreover, a very brief, and
very highly selective, story. We mean to trace the unfolding, across roughly the
last century, of one particular line of thought—a sort of anti-idealism, and also a
sort of anti-empiricism. By focussing in this way we will, inevitably, omit, or give
short shrift to, more than one more than worthwhile Oxford philosopher. We will
mention a few counter-currents to the main flow of 20th century Oxford thought.
But much must be omitted entirely.

Our story begins with a turn away from idealism. Frege’s case against idealism, so far as it exists in print, was made, for the most part, between 1893 (in the preface to Grundgesetze volume 1) and 1918-1919 (in “Der Gedanke”). Within that same time span, at Oxford, John Cook Wilson, and his student, H.A. Prichard, developed, independently, their own case against idealism (and for what might
plausibly be called—and they themselves regarded as—a form of “realism”). Because of the way in which Cook Wilson left a written legacy it is difficult at best to give exact dates for the various components of this view. But the main ideas were probably in place by 1904, certainly before 1909, which marked the publication of Prichard’s beautiful study, “Kant’s Theory of Knowledge”. It is also quite probably seriously misleading to suggest that either Cook Wilson or Prichard produced a uniform corpus from the whole of their career—uniform either in content or in quality. But if we select the brightest spots, we find a view which overlaps with Frege’s at most key points, and which continued to be unfolded in the main lines of thought at Oxford for the rest of the century.

Frege’s main brief against idealism could be put this way: It placed the scope of experience (or awareness) outside of the scope of judgement. In doing that, it left us nothing to judge about. A central question about perception is: How can it make the world bear on what one is to think—how can it give me what are then my reasons for thinking things one way or another? The idealist answer to that, Frege showed, would have to be, “It cannot”.

BV: This is not at all clear. An example would be nice. Let me supply one. I see a tree. The seeing is a perceiving and this perceiving is a mental state of  me, the perceiver.  I see that the tree is green.  Seeing that the tree is green I come  to think that the tree is "one way or another," e.g., green as opposed to not green.  The authors seem to be asking the following question: How can perceiving something -- a tree in my example -- make the world give me the perceiver a reason for thinking the tree to be "one way or another," green for example?

This is a very strange question, one that has no clear sense.  Or at least I don't know what the authors are asking. If the question has no clear sense, then the supposedly idealist answer has no clear sense either. The authors are presumably defending some sort of realism about the objects of sense perception. If so, then it is not my perceiving that makes the world do anything. Their question ought to be: how do physical things in the external world, things that exist and have (most of) the properties they have independently of my or anyone's perceivings, make our perceivings of these things have the content that they in fact have? How does the green tree over there bring it about that I am now having an experience as of a green tree? Or is this perhaps the very question the authors are trying to ask their convoluted way?

But let's read on.

What, in Frege’s terms, “belongs to the contents of my consciousness”—what, for its presence needs someone to be aware of it, where, further, that someone must be me—cannot, just in being as it is, be what might be held, truly, to be thus and so. (This is one point Prichard retained throughout his career, and which, later on, he directed against others who he termed “sense-datum theorists”. It is also a point Cook Wilson directed, around 1904, against Stout (see section 4).

BV:  There is a solid point here, but it needs to be put clearly. The tree is in space and is green. No content of consciousness is in space or is green. Therefore, the tree is not a content of consciousness. This syllogism refutes a form of subjective or psychological idealism. But who holds it? Certainly not Kant. But let's leave Kant out of the  discussion for now. More important than Koenigsbergian exegesis is the deep and fascinating question of idealism versus realism.

What I said in the preceding paragraph needs a bit of refining. If I see a tree, then I am aware of something. That awareness-of or consciousness-of is an episode in my conscious, mental life.  So it is appropriately referred to as a 'content of consciousness.' Now consider that awareness-of just as such.  (Of course, you cannot consider my awareness, but you can consider your own similar but numerically different awareness.) Is it green? No. It is colorless. The awareness-of, as such, is not the sort of 'thing' that could have a color.  

The awareness of green is not a green awareness.  If it were green it would have to be extended in space. No color without extension. But the awareness-of, though it is in time, is not in space.  So here we have a content of consciousness that is neither colored nor in space. 

We should all will agree, then,  that a perceiving as of a green tree is not a green perceiving. This is so even if the perceiving is not merely as of the tree, but of it in the sense that implies that there exists a tree that is being perceived. Again, all colors are extended in space. But no mental act is extended in space. Ergo, no mental act is colored. A fortiori if mental acts  are as G. E. Moore once said, "diaphanous."  

What about the content of a mental act? It too is a 'content of consciousness.' Macbeth had an hallucinatory visual experience as of a dagger. The dagger-appearance is what I am now calling the content. It is clearly distinct (though not separable) from the hallucinatory experiencing.  The hallucinatory act/experiencing is not spatially extended.  What about the dagger-appearance?  Did it not seem extended to Macbeth? Don't pink rats look to be extended in space by that drunks who hallucinate them? Yes they do.  What we can say here is that while the dagger-appearance is phenomenologically extended, it is not extended in objective space. 

But there is a deeper reason for opposing subjective idealism. This I believe to be the solid point that Prichard makes.

If I judge a tree to be green, I judge it to be green whether or not I or anyone so judge it.  So if the tree is green, it is green in itself whether or not there are any perceivers.  The point is quite general: to judge of anything x that it is F is to judge that it is F in itself whether or not there are any judgers. It doesn't matter whether the judgment is true or false: a judgment that x is F purports to lay bare the way things are independently of judgers, whether or not in fact things are as the judgment states. 

So if I say that the perceiving is green, I thereby commit myself to saying that the perceiving is green in itself whether or not there are any perceivers.  But it is contradictory to maintain that something that can exist only as a content of consciousness, and thus cannot exist in itself, can also exist in itself apart from any consciousness.

What I am calling 'the solid point 'puts paid to any form of idealism that identifies physical objects with contents of consciousness if those contents exist only in contingent minded organisms such as human animals.   If there exists a tree that I perceive, it is as little in my consciousness as it is inside my head. But please note that the point just made presupposes the reality of the external world and thus begs the question against those forms of idealism that avoid the mistakes that subjective/psychological idealists make.

So, in particular, it was crucial to Frege that a thought could not be an idea (“Vorstellung”), in the sense of “idea” in which to be one is to belong to someone’s consciousness. The positive sides of these coins are: all there is for us to judge about—all there is which, in being as it is might be a way we could judge it to be—is that environment we all jointly inhabit; to be a thought is, intrinsically, to be sharable and communicable. All these are central points in Cook Wilson’s, and Prichard’s, Oxford realism. So, as they both held (early in the century), perception must afford awareness of, and relate us to, objects in our cohabited environment.

BV: The authors seem to be saying that it is not about ideas, Vorstellungen, contents of consciousness, etc. that we make judgments, but about the common physical environment in which we human animals live.  This remains vague, however, if we aren't told what "the environment" is.  Do they mean particular things in the physical world, or are they referring to the physical world as a whole? And while it is true that thoughts (either Frege's Gedanken or something very much like them) are communicable and thus sharable -- unlike contents of consciousness that are numerically different for numerically different people -- what does this have to do with "the environment"? Fregean and Frege-like thoughts are abstract objects; hence, not to be found in the physical "environment."  Of course, for Frege, thoughts/propositions are not contents of consciousness; it does not follow, however, they are in the "environment."  There are in Frege's third realm, that of abstracta. (I promise to avoid tasteless jokes about the supposedly anti-Semitic Fege and the Third Reich.) 

There is another point which Prichard, at least, shared with Frege. As Prichard
put it:

There seems to be no way of distinguishing perception and conception
as the apprehension of different realities except as the apprehension
of the individual and the universal respectively. Distinguished in this
way, the faculty of perception is that in virtue of which we apprehend
the individual, and the faculty of conception is that power of reflection
in virtue of which a universal is made the explicit object of thought.
(Prichard, 1909, 44)

Compare Frege:

A thought always contains something which reaches out beyond the
particular case, by means of which it presents this to consciousness as
falling under some given generality. (1882: Kernsatz 4) But don’t we see that the sun has set? And don’t we also thereby see that this is true? That the sun has set is no object which emits rays which arrive in our eyes, is no visible thing like the sun itself. That the sun has set is recognized as true on the basis of sensory input. (1918: 64)

For the sun to have set is a way for things to be; that it has set is the way things are according to a certain thought. A way for things to be is a generality, instanced
by things being as they are (where the sun has just set). Recognizing its instancing
is recognizing the truth of a certain thought; an exercise of a faculty of thought.

By contrast, what instances a way for things to be, what makes for that thought’s
truth, does not itself have that generality Frege points to in a thought—any more
than, on a different level, which Frege calls “Bedeutung”, what falls under a (first-level) concept might be the sort of thing things fall under. What perception affords is awareness of the sort of thing that instances a way for things to be. Perception’s role is thus, for Frege, as for Prichard, to bring the particular, or individual, in view—so as, in a favorable case, to make recognizable its instancing (some of) the ways for things to be it does. The distinction Prichard points to here is as fundamental both to him and to Frege as is, for Frege, the distinction between objects and concepts.

BV: Now things are now getting interestingly 'aporetic.' How do I know that the sun has set? I see the sun, and I see the horizon, but I don't literally see (with my eyes) that the sun has set. If the italicized words pick out an entity, it is an invisible one. As Frege says, "That the sun has set is no object that emits rays . . . ."

How do I know that the tree is green? I see the tree, and I see green at the tree, but I don't see that the tree is green. Why not? Well, 'That tree is green' is logically equivalent to 'That green tree exists.' So if I can see that the tree is green, then I can see that the green tree exists. But existence is not empirically detectable. I can sense green, but I cannot sense existence. So I cannot see that the green tree exists.  Therefore, I cannot see that the tree is green.  Existence and property-possession are invisible. More generally, they are insensible, and not because of our sensory limitations, but because existence and property-possession are not empirically detectable by any manner of critter or by any device. 

And yet I know that the tree is green and I know that the sun has set. But how? Frege's answer, "on the basis of sensory input" is lame.  Sure, there has to be sensory input for me  to know what I know in these cases, but how does it work? Such input is necessary, but it cannot be sufficient.  Here is what Frege says in Der Gedanke:

Das Haben von Sinneseindruecken ist zwar noetig zum Sehen der Dinge, aber nicht hinreichend. Was noch hinzukommen muss, ist nichts Sinnliches. (Logische Untersuchungen, 51)

To be sure, the having of sensory impressions is necessary for seeing things, but not sufficient. What yet must be added is nothing sensory.

Necessary, because seeing (with the eyes) is a sensory function that cannot occur without sensory data, which is to say, sensory givenness, sensory input. Not sufficient, because what I need to know to know that that the tree is green, is that the physical individual/object does in reality instantiate the concept/property. The problem is that I cannot see the copulative linkage in the green tree any more than I can see the existence of the green tree. For again, to see either the linkage or the existence I would have to be able to sense them when there is no sensory awareness of either.  

What Frege adds that is not sensory is the thought/proposition. But this item is off by itself in a platonic topos ouranios. How on Earth or in Plato's Heaven can Fregean thoughts avail anything for the solution of our problem? To know that the tree is green in reality I need to know the sublunary unity of thing and property here below. How is that knowledge aided by the positing of a 'ouranic' item, the thought/proposition, whose subject constituent is an abstract item as abstract as the thought itself? The Fregean thought brings together a subject-constituent, a sense, with a predicate-constituent, also a sense.  It does not bring together the concrete tree and its properties.

What the authors say above on behalf of Frege and Prichard is thus no answer at all. We are told, "Perception’s role is thus, for Frege, as for Prichard, to bring the particular, or individual, in view—so as, in a favorable case, to make recognizable its instancing (some of) the ways for things to be it does."  Are they joking?  This glides right past the problem.  What I need to know to know that the tree is green is the linkage or togetherness of individual and property in the thing in the external world. The thing is a this-such or a something-which. You cannot split the this from the such.  You cannot split perception from conception assigning to the first the job of supplying bare individuals and assigning to the second the job of providing universals.  For the problem, again, is 'methectical,' a problem of methexis: how do sensory individual and  intelligible universal meet to form the sublunary this-such?

Kant has an answer (whatever you think of it): the synthesis of individual and property/concept is achieved by the transcendental unity of apperception! 

I will have more to say about this in a later post.

Could the Visible Surface of a Physical Thing be a Mental Item?

The Sparring Partner offers the following tetrad for our delectation. 

1) I take this to be the visible surface of a desk.

2) It is almost certain that this in fact [is] the visible surface of a desk, but it is possible that it is not (it may be the result of a highly realistic virtual reality program).

3) If this were not the visible surface, it would be a mental item.

4) It is impossible that the visible surface of a desk could ever be a mental item.

The S. P. thinks that these four are collectively inconsistent.  That is not true. They are consistent on the following theory. 

My man sees something.  One cannot see without seeing something. This is a special case of the thesis of intentionality. What my man sees, the intentional object, has the properties of a desk surface; it has the look of a desk surface. What he sees may or may not exist. (Better: what he sees is possibly such that it exists and possibly such that it does not exist). The intentional object is bipolar or bivalent: either existent or non-existent. In itself, the intentional object is neutral as between these two poles or values.  If the intentional object does not exist, then it is merely intentional. If the intentional object exists, then it is real.

So far I have accommodated (1) and (2). 

If the intentional object is real, then it it part and parcel of the desk itself.  If so, then the intentional object is not a mental content. This should also obvious from the fact that the intentional object is distinct from the corresponding act: it is not contained in the act, and in this sense it is not a content (reeller Inhalt in Husserl's sense) of the act.  The act is mental, but is object is not mental, or at least not mental in the same sense. The act is an Erlebnis. it is something one lives through (er-leben); one does not live through an intentional object. Call the intentional object the noema. The noema is not a mental content but it it also does not exist in itself. It exists only as the objective correlate of the act.  It is other than the act, and not contained in the act, but is nonetheless  necessarily correlated with the act such that, if there were no acts (intentionale Erlebnisse), then there would be no noemata. 

I have just now accommodated (3) and (4).  I have shown how the members of the tetrad could all be true.  An apparently  inconsistent set of propositions can be show to be  consistent by making one or more distinctions. In this instance, a distinction between mental item as content and  mental item as noema. 

The answer to the title question, then, is yes.

Here is a simpler and more familiar example of how this works. The aporetic dyad whose limbs are The coffee is hot and The coffee is not hot is apparently inconsistent.  The inconsistency is removed by making a distinction between two different times one at which the coffee is hot, the other at which it is not.

Is the above theory, which I have only sketched, tenable? Does it definitively solve the problem? I don't believe so. And this for the reason that the solution gives rise to problems of its own. 

If a polyad is solved by the making of a problematic distinction, then the solution is stop-gap and not definitive.

On Perceptual 'Taking'

Ed writes,

Something to think about. “I take an X to be a Y”.

This can be true when there is no Y. For example, I take a tree root to be a snake. There is a tree root, but no snake.

But what about the other way round? I take a mirror image to be a person occupying the space behind the mirror, thinking it to be a window. In that case there is also no Y (because no such person) but is there an X? That is, does “I take a mirror image to be a person” imply that there is some X such that X is a mirror image and I take X to be a person?

It is the ‘ontological’ (=referential) questions that interest me. I have never had any interest in epistemology. Is a mirror image a τόδε τι, a hoc aliquid, a this-something?

Over to you.

BV:  I don't believe anyone who knows English would ever say, 'I take a tree root to be a snake' as opposed to 'I took a tree root to be a snake.'  If you see something that you believe to be a tree root, then you cannot at the same time take it to be a snake.  If, on the other hand, if you take something to be a snake, and further perception convinces you that it is a tree root, then you can say, 'I took a tree root to be a snake.'

Suppose we try to describe such a situation phenomenologically. I am hiking in twilight through rattlesnake country. I suddenly stop, and shout to my partner, "I see a snake!" People say things like this. What we have here is a legitimate ordinary language use of 'see.'  Sometimes, when people say 'I see a snake,' there is/exists a snake that they see.  Other times, when people say, 'I see a snake,' it is not the case that there is/exists a snake that they see.  In both cases they see something. This use of 'see' is neutral on the question whether the seen exists or does not exist. Call this use the phenomenological use. It contrasts with the 'verb of success use' which is also a legitimate ordinary language use. On the success use, if subject S sees X, it follows that X exists.  On this use of 'see,' one cannot see what does not exist. On the phenomenological use, if S sees X, it does not follow that X exists. Mark the two senses as see_s  and see_p respectively.

I see_p a snake. But as I look more closely the initial episode of seeing is not corroborated by further such episodes. The snake appearance of the first episode is cancelled. By 'appearance' I mean the intentional object of the mental act of seeing_p. This appearance (apparent item)  is shown to be a merely intentional object. How? By the ongoing process of visual experiencing. The initial snake appearance (apparent item) is cancelled because of its non-coherence with the intentional objects of the subsequent perceptual acts. The subsequent mental acts present  intentional objects  that have some of the properties of a tree root. As the perceptual process continues through a series of  visual acts the intentional objects of which cohere, the perceiver comes to believe that he is veridically perceiving a tree root. He then says, "It wasn't a snake I saw after all; I took a tree root to be a snake!"

Clearly, I saw something, something that caused me to halt. If I had seen nothing, then I would not have halted. But the something I saw turned out not to exist.

So my answer to your concluding question is in the affirmative.

Finally, if you have no interest in epistemology, then you have no interest in the above question since it is an epistemological question concerning veridical and non-veridical knowledge of the external world via outer perception.

You are some kind of radical externalist.  But how justify such an extreme position? 

A Kantian Aporia?

This just in:

I know you like puzzles in aporetic form, so here you are.

1. My perception involves (though is not necessarily limited to) the immediate awareness of mental phenomena.

2. When I look at the visible surface of this desk, all I am immediately aware of is the visible surface of this desk.

3. The visible surface of this desk is not a mental phenomenon.

All three cannot be true. If (1) is true then my perceiving the desk involves the awareness of mental phenomena. Note that this does not assert that the visible surface of this desk is a mental phenomenon, only that, if it is not, then I must be immediately aware of some mental phenomena in addition to my awareness of the desk.

But (2) says that the visible surface of this desk is all I am immediately aware of. Hence (3) cannot be true.

Likewise, if (2) and (3) are true, (1) is false, and if (1) and (3) are true, (2) is false.

Nicely presented. I agree that the three propositions are collectively inconsistent: they cannot all be true. But there is an interesting problem here only if the propositions are, in addition,  individually plausible.  The more plausible, the tougher the problem. 

(3) is plausible to a high degree. (Plausibility, unlike truth, comes in degrees.)  A desk is a physical thing. The surface of a desk is a physical part of a physical thing. A mind, its states, and its contents are none of them physical.  An occurrent episode of visual perceiving is a mental phenomenon.  So, yes, (3) is highly plausible and I would rank it as the most plausible of the three propositions.  

(2) is the least plausible of the three. It is true that when I look at my desk I do not see my visual perceiving of the desk or of some part thereof.  But it does not follow that I am not aware of my perceiving.  Right now, as I stare at my desk, I am not only visually aware of  (part of) the desk; I am also aware of being visually aware of it.  This is what Franz Brentano calls innere Wahrnehmung, inner perception, which he distinguishes from innere Beobachtung, inner observation. This ongoing inner perception, or rather perceiving, is a simultaneous secondary awareness of the primary 'outward' visual awareness of the (surface of) the desk.

This inner awareness of being outwardly aware of something is not the same as full-blown reflection which one could, but need not, express by saying 'I am now seeing the surface of a desk.'  It also must be distinguished from the type of awareness in which I am outwardly aware of something without being aware of being aware of it at all. Suppose you have been driving for some time, stopping at the red, going at the green, negotiating turns, etc. when you suddenly realize that you have no memory of doing any of those things. And yet your present physical integrity shows that you must have been aware of all those traffic changes. You were outwardly aware via the five outer senses without being explicitly aware of being aware or implicitly aware via Brentano's inner perception. 

And so I solve the above problem by rejecting (2).  (2) is the least plausible of the three and a very strong case can be made for its being false.

(1) leaves something to be desired as well. Later on this.

So we don't have an aporia in the strict sense, an intellectual impasse, or insoluble problem.  And even if we did, it is not clear what this has to do with Kant.