Logical and Spiritual REFLECTIONS
Book 3. In Defense of Aristotle’s Laws of Thought
Chapter 17. The status of sense perceptions
I would like here to explore some more aspects of the controversy between Materialism and Mentalism. Note that both views are here taken to acknowledge mental phenomena: the mentalist (or mind-only) view accepts mental phenomena to the exclusion of material ones, whereas the materialist view (as here understood) accepts material phenomena without excluding mental ones from the world (though it circumscribes their occurrence in “minds” like ours).
Is sense perception objective (and therefore valid) or subjective (and therefore invalid)? That is, is the world we perceive apparently through our sense organs material, or is it as mental as the phenomena we project in our imaginations? Most people, including most scientists and philosophers, accept things as they seem at the outset, and opt for the materialist thesis. But some philosophers, like George Berkeley in the West or the Yogacara School in the East, would argue that this ‘common-sense’ conclusion is rushed, and prefer the mentalist alternative.
The latter suggest that the whole notion of sense-organs is flawed, because if we suppose that there is a cognizing entity enclosed in a physical body with organs of sensation, through which information of other physical bodies beyond is obtained, the information actually cognized by the subject-entity is not the physical objects supposedly in contact with the sensory receptors, but mental products of such supposed objects at the other extremity of the process of sensation, i.e. directly opposite the one cognizing.
If, then, what we actually perceive are not physical objects but assumed mental products of them – it follows that all our actual objects of perception are all mental and none are material. That is, even our apparent body (including the sense organs it seems to contain) is effectively a mere mental phenomenon; and there is also no reason to suppose that the material world apparently beyond them is anything but mental.
That is, concluding this line of argument, the very distinction between mental and material must be abandoned as a silly idea, and only mental objects admitted as real. Phenomena ordinarily classed as material are just as mental as imaginings (though perhaps less readily controlled). Their appearance is real enough, but their materiality is illusory. Thus, materialism is a naïve philosophy, and mentalism is the correct doctrine.
I have in the past always argued that this skeptical argument is logically self-contradictory, because it starts with an assumption that the body and its sense organs exist in a material sense, and ends with the conclusion that there are no such material body and sense organs. A conclusion cannot contradict the premise(s) it is drawn from – so this argument must itself be logically flawed.
But now it occurs to me that this counter-argument of mine might be unfair, and I wish to review it. It occurs to me that it is formally acceptable for a conclusion to contradict its premise(s) – this is just what (single) paradoxical propositions mean. A proposition of the form “If P, then not P” is logically quite legitimate (if not accompanied by a second proposition of the form “If not P, then P”, for in such case we have an insoluble double paradox, i.e. a contradiction). The logical conclusion of “If P, then not P” (alone) is the categorical proposition “Not P”.
In the case under scrutiny, the premise P is “there is a material body with sense organs” and the conclusion NotP is “there is no such thing” – and such inference is quite thinkable, quite legitimate according to the laws of thought. That is, rather than view the argument presented by the skeptics as self-defeating, we might suggest that they have shown materialism to be inherently paradoxical and thus self-contradictory, and rightly concluded mentalism to be the only internally consistent thesis of the two!
However, I have seen through this line of argument from the start, when I contended, in my Future Logic (chapter 62), that the solution to this conundrum was to deny the idea that what we perceive, when we seem to perceive material objects through the senses, are mental images of such material objects. I believe this is the error of conception regarding the nature of sense perception, which is logically bound to result in skepticism. John Locke made this error, and David Hume was quick to spot it (though he could not correct it).
Locke was well intentioned, intent on justifying common sense; but his scenario was imperfectly conceived, and sure to lead to Berkeley’s radical conclusion. However, there is a logical way out of the difficulty – and that is to conceive the sense organs as somehow allowing us to perceive the material objects themselves, or (more precisely) at least certain aspects of them, rather than only some mental products of them. If you reflect, you will realize that this is what we ordinarily assume we are doing when we perceive the world seemingly around us.
This is of course a hard scenario to explain, but it provides a possible justification for materialism (a self-consistent, non-naïve version), and thus an effective defense against the skeptical conclusion of mentalism. In this manner, the paradox inherent in naïve materialism is not ignored or denied, and yet the mentalist conclusion is not drawn from it, because a third thesis is proposed.
This third thesis is that sensation, rather than implying indirect perception, makes possible direct perception (perhaps by producing some sort of physical structure in the brain serving as a passageway for the Subject’s consciousness to get in direct contact with the object sensed). This thesis is not, by its mere formulation, definitively proved, note well; but at least it serves to put the mentalist doctrine in doubt.
We are in this manner provided with two competing hypotheses, both of which seemingly equally account for experience; and the question of materiality versus mentality of the objects of certain perceptions is thus reopened. The issue is turned from a deductive one (favoring mentalism) to an inductive one (in which both doctrines are at least equally conceivable).
I thereafter posit further argumentation to show the reasonableness of the common sense (materialist) view. Since the matter-mind distinction is itself based on that view, it cannot be used by mentalists to declare all objects mental rather than material. Given their view, no such distinction would arise in the first place, and we would have no understanding of the different intentions of these two words.
Moreover, I have suggested that the distinction might be phenomenologically explicable, by saying that mental phenomena are merely visual and/or auditory, but lack other phenomenal qualities. Mental phenomena correspond to those experienced through sight and hearing, whereas touch, smell and taste sensations seem to have no equivalent forms in the mind. Our memories can recognize them, but they seemingly cannot reproduce them.
In other words, we perhaps recognize materiality by virtue of touch, smell and taste sensations, granting that the mental domain lacks these specific phenomenal modalities. Visual and auditory phenomena are ambiguous, i.e. they might be material or mental; but (I tentatively suggest) the other modalities are distinctively material.
An explanation for this may be that the senses of touch, smell and taste are biologically more basic, while those of sight and hearing occur further up the evolutionary scale. The former are more qualitative and pleasure-pain related, applicable to any sentient being, whereas the latter are more spatial and temporal, implying a more complex form of life.
It is also important to note that mentalists consider consciousness of mental objects as needing less explanation than consciousness of material objects. To them, knowledge through the senses is hard to explain, in view of the distance of the knowing subject from such objects; whereas, mental objects are more knowable because closer to us. Or if it is not an issue of distance to them, perhaps they consider that the knower is of the same substance as mental objects.
But we must realize that consciousness of mental objects is just as marvelous, mysterious and miraculous as consciousness of physical objects.
To regard mental objects as of the same stuff as the knowing self (because we colloquially lump these things together as constituents of the ‘mind’ or psyche) is an error. Mental objects like memories, imaginations or ideas are not themselves conscious: they are always objects, never subjects of consciousness; therefore they cannot be essentially equated to the soul that knows them.
As for distance: on what basis are physical objects regarded as further afield than mental objects? Such spatial considerations are only possible if we locate the soul in a continuum including mental and material objects. But in truth, we do not strictly believe in a continuum common to both mental and material objects, although some mental projections (hallucinations) do sometimes seem to inhabit the same space as physical things. Furthermore, we do not know the exact ‘place’ of the soul: is it in the heart or in the brain or coterminous with the body or outside it – or is it in some other dimension of being altogether?
It should be added that consciousness of oneself, i.e. the intuition of self by self, is essentially no different from these two kinds of consciousness: only the objects differ in the three cases. That is, whether the objects are mental, material or spiritual in ‘substance’, consciousness is still one and the same sort of special relation. The same reflection also applies to eventual ‘transcendental’ consciousness, i.e. consciousness of God or of the Ultimate Ground of Being – this is still consciousness. Whatever the kind of object involved, consciousness remains marvelous, mysterious and miraculous.
Thus, asserting mentalism instead of materialism is not as significant for the theory of knowledge as might at first sight seem. The apparent gain in credibility in such change of paradigm dissolves once we pay attention to the question: but what is consciousness?
 See also earlier comments of mine on this issue, in Future Logic (chapters 60-62), Buddhist Illogic (chapters 4 and 5), Phenomenology (chapters I-IV), Ruminations (chapter 2, Sections 16 and 17), and Meditations (chapter 32).
 I simply ignore the “matter-only” hypothesis, known as Behaviorism in modern philosophy and psychology, because that hypothesis is clearly unscientific, since it deliberately ignores all mental phenomena, treating them as non-existent (and not merely as rarified forms of matter). Mental phenomena are phenomenological givens, and cannot be just waved-off as irrelevant. That we cannot to date materially detect and measure them does not justify a materialists thesis, since this would constitute a circular argument.
 I.e. only in conjunction with “If not P, not-then P”.
 Incidentally, in the Western philosophy of the Enlightenment (not to confuse this label with the Buddhist sense of ultimate knowledge, of course), the word “sensation” was used too vaguely. No great distinction was made between touch, smell and taste sensations, on the one hand, and visual and auditory sensations, on the other.
[Note that we linguistically tend to relate the touch, smell and taste senses. Thus, in English, ‘feeling’ may refer to touch-sensations (including hot and cold tastes), sensations of bodily functions (digestive, sexual, etc.), visceral sentiments (in body, of mental origin), or vaguely mental emotions; and ‘sensing’ may refer to physical sensations, or vague mental suspicions. Also, in French, the word ‘sentir’ corresponds not only to the words ‘to feel’ and ‘to sense’, but also to ‘to smell’ (whence the English word ‘scent’).]
Yet, the three former sensations are far more easily misinterpreted than the latter two. E.g. it is far more difficult for us humans to identify someone based on touch, smell or taste sensations, than on visual or auditory sensations. By this I mean that touch sensations (etc.) usually tell us of a condition of our own body caused by some other body external to it, whereas sights and sounds are aspects of the external object itself that we (the Subject) somehow perceive. At least, this is the way things seem to us at first sight. We must still, of course, move from such Naïve Realism to a more Subtle Realism. In any case, each mode of sensation has its value, and they should not all be lumped together.
By the way, another vague term in this school has been “ideas”. This term tends to have been used indiscriminately, sometimes applied to perceptual memories, or again to visual or auditory projections, and sometimes applied to conceptual constructs, whether or not verbal. Yet, these different mental ‘entities’ have very different significances in the formation of knowledge. Clearly, relatively empirical data has more weight than more abstract productions. Making distinctions between different sorts of “sensations” and “ideas” is very important if we want to accurately evaluate the constituents of knowledge.
 Especially touch. Note how one sense of the term ‘substantiality’ is the hardness of a material object in reaction to touch. Solids are most substantial, resisting all pressure. By contrast, in view of their yielding, liquids are somewhat less substantial, and gases least of all. But all states of matter are also known to some extent through other sensations, like heat and cold, etc.