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Mitchell_Porter comments on Can't Unbirth a Child - Less Wrong

24 Post author: Eliezer_Yudkowsky 28 December 2008 05:00PM

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Comment author: Mitchell_Porter 19 June 2012 05:59:39AM 0 points [-]

To understand my position, first see this latest comment. It is that physical ontology is a subset of the true ontology, a bit like replacing a meaningful communication with a tree diagram. The tree structure is present in the original communication, and it inhabits everything to do with syntax and semantics, but the tree structure does not in itself contain the meaning.

Analogously, everything following "...which is formally..." is the abstracted description of consciousness, in mathematical/physical terms. The true ontology is the stuff about monadic intentionality with a subjective pole and an objective pole. My supposition is that this takes a finite number of bits to describe, and if you were to just talk about the structure and dynamics of those bits, solely in physical and computational terms, you would find yourself talking about (e.g.) nested qubit structures in the Hilbert space of entangled microtubular electrons. (That last is not a hypothesis that I advance with deadly seriousness and specificity, it's just usefully concrete.)

So if you want to talk about the basis of perception and knowledge, there are two levels available. There is the physical-computational level, and then the level of "true ontology". Perception and knowledge are really concepts at the deeper, truer level, because in truth they involve the "subjective" categories like intentionality, as well as the purely "objective" ones like structure and cause. But they will have their abstracted counterparts on the computational level of description.

In principle, the way we learn about the scientifically neglected subjective side of ontology is through phenomenology, i.e. introspection of an unusually systematic and rigorous sort, usually conducted in a doubting-Cartesian mode in which you put to one side the question of whether there is an external world causing your perceptions, and just focus on the nature of the perceptions themselves. Your question - what's going on when you perceive something as red, what's going on when you perceive fourness, and is there any difference - should be answered by introspective comparison of the two states.

In practice, any such introspection and comparison is likely to already be "theory-laden". This is one of the difficulties of the subject. Consider the very idea of intentionality, the idea that consciousness is all about a subject perceiving an object under an aspect. Now that I have the concept, it seems ubiquitously valid - every example of consciousness that I come upon, can be analyzed this way - and that offers a retroactive validation of the concept. But I can't say that I know how to get into a subjective state whereby I am agnostic about the existence of intentionality, and then have the intentional structure of consciousness forced upon me anyway, in the way that the existence of colors is impossible to deny. Maybe it becomes possible, at a higher level of phenomenological proficiency, to achieve a direct awareness of the reasons for believing in intentionality; or maybe it's a concept that is only ever validated in that retroactive way: once you have it, it becomes supremely plausible because of its analytical utility, but it's something that you have to hypothesize and "test" against the phenomenological "data", it's not something you can just "see directly" in the data.

My ideas about the difference between perceiving redness and perceiving fourness are on that level, at best; they are ideas that I picked up somehow, and which I can test against experience, but for which I don't have a subjective procedure which demonstrates them without presupposition, which is the epistemological gold standard for phenomenology...

A perceptual state of consciousness involves a "total object" which is "present" to a subject. This total object is what I called the "total instantaneous phenomenal state of affairs", by definition it's the union of all current objects of awareness; the "world" you are experiencing at a given moment. Some of these objects will be continua of qualia; for example, the total visual component of an experience. The subjective visual field is part of the world-object, along with other sensory continua. The subjective visual field isn't homogeneous, its hue, intensity, and value varies from location to location. This variation constitutes its form.

So far this is just a crude ontological analysis of the object end of an experience. When you ask how we perceive redness and fourness, you're also asking for an ontological analysis of how the object end relates to the subject end. In principle, that should derive from a phenomenological analysis of perceiving red and perceiving four... The trouble lies in distinguishing the component of the experience which is posited, from the component of the experience which is "given" - the part of the experience which is just there. I think fourness is posited on the basis of simpler local structural forms which are given, and I think there is a crude difference between red and, say, green, which is given, but more specific identification of colors requires conceptual synthesis, e.g. you have to notice that the shade of color is not just red, it's also dark, and then you can say it's a dark red.

Bertrand Russell and others talked about "knowledge by acquaintance" versus other forms of indirectly obtained knowledge; "knowledge by acquaintance" is the direct knowing that comes from direct awareness. So that which is given is known by acquaintance, and that which is posited is at best known to be consistent with experience. In this language, we know a shade of color as red-not-green by acquaintance, and we know that it is dark by acquaintance, but we know that it is dark red only by conceptual synthesis. And I think that a perception of fourness similarly arises from conceptual synthesis of more primitive facts that we know by acquaintance...

But one of the most challenging things is to say something convincing or even comprehensible about the direct awareness of objects by a subject. Should we treat qualia and this "total object" as part of the self, or as something external to the self that it's "aware of"? Is the awareness something that is caused by a particular relation between self and object, or is it the relation itself?

It's quite understandable why people prefer to focus on neurons, computation, and impersonal descriptions. If the physical side of my idea were ever validated, this would mean focusing on qubits, electron states, and so forth. But in the end, the vague and confusing subjective language of subject, object, awareness, acquaintance... would have to apply to entities and relations for which we also had a physical description. The "objective pole of the monadic intentionality" might correspond to "the union of all the leaves of the tree in the quantum data structure", and the "subjective pole" might be "the union of all the edges connected to the root node". (Undoubtedly that's not how it is, but again, concrete example for the purpose of discussion...)

You see intimations of this promised fusion between neurophysical, computational, and subjective ontologies when people have a feeling that it's all come together in their heads in a marvelous heap. "I am the computation, as well as the computer performing the computation!" might be how they express it, and behind this is a cognitive phenomenology in which there has been a miniature crossover and fusion of specific concepts from the different ontologies. I don't believe anyone has yet seen the truth of how it works, but the occasional illusion of insight gives us a foretaste of how the actual knowledge would feel, and meanwhile we need to keep switching back and forth between speculative synthesis and critical analysis, in order to make incremental progress. I just think getting to the answer requires a big leap in a new direction that's hard to convey.

Comment author: TheOtherDave 19 June 2012 12:53:02PM 1 point [-]

If you intended to answer my question, you might want to know that after reading your response, I still have no idea whether on your account perceiving some system as comprised of four things requires some ontologically distinct noncomputational something-or-other in the same way that perceiving a system as red does.

If you intended to use my question as a launching pad from which to expound your philosophy, or intended to be obscurantist, then you might not.

Comment author: Mitchell_Porter 19 June 2012 03:20:14PM *  1 point [-]

I still have no idea whether on your account perceiving some system as comprised of four things requires some ontologically distinct noncomputational something-or-other in the same way that perceiving a system as red does.

Aha! Only now do I understand exactly what you were asking.

Recap: I complain that colors, such as redness, exist in reality, but not in physics as we describe it now, not even in the physics of the brain. So I just postulate that somewhere in the brain are entities, "manifolds of qualia", which will have a naturalistic, mathematical description as physical degres of freedom, but which in their full ontological reality are actually red.

So great, I've "saved the phenomenon", my ontology contains true color. But now I need an ontological account of awareness of color. Reality contains awareness of redness, just as much as it contains redness. This is why I started talking about "positing" and "givenness" and the subjective pole of intentionality - because that stuff is needed in order to say what awareness is.

The question about fourness starts out looking simpler than that. If you asked, Does your ontology contain redness, I can say, Yes; it contains qualia-manifolds, and they can be genuinely red. The question about fourness seems quite analogous. If there is a square in your visual field, do I claim that there is a platonic property of fourness inhabiting your manifold of visual qualia?

I believe in the existence of colors, but I am a skeptic about the existence of numbers. You might get away with a metaphysics in which there are no number-entities, just states of processes for counting. I'm not sure; if numbers are real, they might be properties of collections... but I'm a skeptic.

More importantly, my ontology of conscious states gives redness and fourness a different status, which allows me to be agnostic about whether or not there's a real "essence of fourness" inhabiting the visual sensation of a square. I hypothesize that the entity "redness" (more precisely, a particular shade of redness) is itself part of the entity, "awareness of that shade of redness"; but that "awareness of fourness" does not contain any correspondingly real "fourness". Analysed, it would be more like "awareness of a group of lines to which the concept of fourness is posited to apply", or perhaps "awareness of a group of lines together with the awareness that they are being categorized as a foursome by your nervous system". I'm willing to countenance a functionalist account of number "perception", but not of color perception.

I hope that this answer, if not intellectually satisfying, at least addresses the question. And now, back to work for a few days...

Comment author: TheOtherDave 19 June 2012 04:17:24PM 1 point [-]

I believe in the existence of colors, but I am a skeptic about the existence of numbers. You might get away with a metaphysics in which there are no number-entities, just states of processes for counting. I'm not sure; if numbers are real, they might be properties of collections... but I'm a skeptic. [..] I'm willing to countenance a functionalist account of number "perception", but not of color perception.

OK, cool. That does indeed address the question, thank you.

When you have the time, I would be interested in your thoughts about what sort of evidence might convince you that a functionalist account of number "perception" is inadequate in the same way that (on your account) a functionalist account of color perception is.