Supervenience Phenomenalism

Supervenience phenomenalism; all facts about the universe are actual or possible sense experience. Two worlds which are the same in sensory facts are the same in physical facts. There are not two universes in which physical facts are the same and sense facts are not the same.

Phenomenalism is the philosophy that facts about physical objects are dependent upon or are entirely explainable in facts about actual and possible sensory experiences. Supervenience is a relationship where no two things can differ in their fundamental properties without also differing in their different respective properties. The biological supervenes on the physical and the chemical in that changes in the physical and chemical mean a change in the biological, but not the other way around. This doesn't mean all things like social groups can be reduced to fundamental particles, as there are multiple and higher levels of properties. But sense data is the most fundamental kind of thing there is which everything else depends on. The mental and the physical supervene on sense experience. A change in sense data means a change in the physical and the mental

Phenomenalism is committed to a third type of thing in the universe, sense data, which can be distinguished from mental and physical phenomena by their 1) subjective content and 2) being externally caused. Sense data is mind independent and physical in the causal sense, but not physical and mental in its subjective nature, existing independently of physical objects said to cause them. Sense data is always known to a mind, but mind doesn't constitute them; they constitute mind and anything that is thought about. Sense data is the fundamental basis for both mental and physical properties.

Critics can use a similar argument used against Platonic forms. That is that sense data is redundant, as it only explains the mental and the physical by being self existing. But applying Occam's razor and eliminating sense data would not make the explanation of mind better than the physicalist position. Mind would remain hard to explain given contemporary physicalist approaches such as eliminativism, identity physicalism, behaviorism, and functionalism.

There are reasons to assent to the belief in sense data as the single ontological substance. The most relevant reason to philosophy of mind is that it answers the hard problem of consciousness, accounting for qualia. As a neutral monist philosophy, the relation of body and mind is answered. Phenomenalism is also completely compatible with the conclusions of science, which are revisable in the face of experience. It is my opinion that phenomenalism provides us all the benefits of physicalism while giving a satisfying account for subjective experience and the relationship of mind and body.

The major objection to phenomenalism is an objection to translational phenomenalism, now considered untenable. According to translational phenomenalism, claims about physical objects share the same meaning as a claim about actual or possible sense experience. There is not a physical fact that cannot be translated into a sensory experience fact. The claim that there exists a table so that the claim there is a table in this room is true can be translated as if one were to extend their hand in front of them, they would feel the hard surface of what we call a table. There exists a tactile sensation of the skin so that there is a table in the room is true.

The problem with this kind of argument is that no purely sensory claim is necessary for any given claim that a physical object exists. If the sensation can be realized in different ways, by illusion or hallucination, then the sense experience said to correspond to a physical claim is not necessary. If I try to convince someone who is blind there is a Lego brick in front of them, I could say that if you keep walking, you will feel pain in your foot (assume they're barefoot). But the blind individual could feel pain if there were other things there, or even be in pain if there wasn't anything on the floor (perhaps by my suggestion).

This criticism is widely considered to have defeated phenomenalism. Physicalism however was able to survive similar objections decades ago by adopting supervenience. Identity physicalism was criticized on the similar grounds of multiple realizability, that a mental experience can be caused by different physical events. It is practically impossible to demonstrate a physical event for each mental event. Functionalism was proposed to remedy this; mind is a causal relationship between material things. Mind is defined by what it does, as Steven Pinker puts it, "the mind is what the brain does." Functionalism is an epistemology; the related ontology is supervenience. Supervenience is a one way dependency on one state of objects on another. Mind only exists if matter exists, but matter exists if mind doesn't exist. Mind is then a level of material functioning which depends on more fundamental material function, at the biochemical level.

Causal relations however are not necessary relations. We establish the relation between activity of the brain and thought by inference, not by fact. The mind is associated with what the brain does. Per Hume, there is no necessary connection among different things. No amount of experience can demonstrate that one thing always follows another, if they are different. Bringing in Leibniz's law, the Identity of Indiscernibles, what can be said about mind cannot all be said about the physical body. Here I invoke such properties from three arguments; disembodied existence, divisibility, and introspection. 

Disembodied Existence:
1. My mind can exist separate from anything physical.
2. No physical part of me can exist separate from anything physical.
3. Therefore, by Leibniz's Law, my mind isn't a physical part of me.

Divisibility
1. My physical parts are divisible.
2. My mind is not divisible.
3. So my mind is distinct from any of my physical parts (by Leibniz's Law).

Introspection
1. I can come to know about my mind (mental states) by introspection.
2. I cannot come to know about my brain (or any physical states) by introspection.
3. Therefore, my mind and my physical parts are distinct (by Leibniz's Law).

There is no necessary relationship between different things. If the mental and the physical are different in kind, then their relation is inferential, and more reliant on induction. If two things are different, we have no idea in the mind of their connection for if there is something there, it belong either to one of them or to something else. Only by a number of different experiences, more than one at least, can we infer a causal relationship. But this then depends on induction which does not operate on necessity, as we can imagine that there is no causal relationship at all without being in contradiction.

Since mental properties differ from physical properties, if we want to assert some causal or ontological relation, we must assent to the existence of a third class of objects which is not predicated of anything else, as it is capable of explaining the properties of mind and body.

Physical objects are a class of sense experience. Subjective experiences, the mental, is known to us more intimately via introspection and can be considered a lower class of ontological functioning which can exist without corresponding physical objects, isn't conceivable in spatial temporal extension, and is of more direct knowledge.

An epistemological alternative to phenomenalism is indirect realism. Indirect realism, representational realism or causal realism stands between strict physicalism which is realist about the existence of mind-independent physical objects and phenomenalism which acknowledges properties which are subjective and together with physical properties make up the world. Indirect realists agree that qualia exists and our perception of objects does not always correspond with their true nature, but think that qualia is caused or is explainable by the interaction of external objects on mind. The position is compatible with non-reductionist versions of physicalism as physicalism is ontological and indirect realism is epistemological.

Indirect realism faces a similar problem as physicalism does ontologically. How does one infer the existence of a whole class of objects when one only has access to perceptual experience? This is a vertical inference rather than a horizontal inference. Phenomenalism makes horizontal inferences about objects and their relations; from one sense experience to another sense experience.

The causal realist account since Descartes is that since we can infer our own existence, why can't we infer the existence of other entities like we did with ourselves? Incidentally this is also at the foundation of idealism, though with only minds of others and God as objective. I think and there are thoughts, so must I exist to have them? But all we actually have are thoughts, many of which are not causally ascribable to the self. Thoughts can exist whether or not we think them. And there is no particular thought which the self can be located. Like can only come from like, idea from idea. So it is not necessary to explain the effects we have, ideas, by anything greater than ideas.

The nature of objects is known by abstraction, which is really separating certain qualities of something which are able to exist on their own. We can imagine a horse which has lost a leg to still be a horse for example. But our prior notion of a horse is itself a collection of properties, which at a certain point enough satisfy our notion of what a horse is. Even if we were born with an idea of a horse, it would still be an idea in the mind which would not guarantee the objective existence of such a creature, much as we are able to imagine unicorns or the god Cthulhu. We are always abstracting with what we already know, to try to discern a common relationship with similar phenomena.

Indirect realists assume a distinction between properties which actually belong to an object and those which are only perceptual and caused by objects; primary and secondary qualities. Spatial qualities are supposed to be primary qualities, and the phenomena of color and sound are secondary. The real distinction however is that primary qualities are a priori features of the mind, prior to individual experience, which are imposed on objects of perception by the nature of individual consciousness. There is an intellectual nature to perception, besides its intuitive, non-reflective nature. We can only intellectually comprehend reality in certain ways. For we conceive of reality as having three dimensions but the math of physics tells us that there could be many other spatial dimensions. We can infer those dimensions insofar as they are instrumental towards understanding the universe, affecting what we do perceive. There is no reason to assume the a priori way we understand things apply to the universe itself. All we have of the universe is sense experience, particularly in astronomy where most of the data is from wavelengths of the light spectrum. We shouldn't hold some our intellectual notions above what the data tells us.

Supervenience phenomenalism doesn't have the difficulty of inferring a class of objects different and independent of what we experience. The real problem of knowledge is that we try to reason more than is necessary. Supervenience phenomenalism passes two critical tests: Occam's razor and compatibility with science. It is more simple but not too simple when it comes to explaining the mental and the physical, and avoids reifying scientific concepts into comfortable anthropomorphisms.

A potentially disappointing consequence of supervenience phenomenalism is that much of what people consider mind or non physical can actually be explained physically since all of what physicalism says still holds. The only thing not explainable by the physical are subjective mental images, not any sorts of composite objective entities. The soul, God, the afterlife, ghosts only exist as subjective sense data or physical facts. If neither of those, then there is nothing in of themselves which can be said to be true or false. Mind and body are not truly distinct things, but different aspects abstracted from the sort of thing.