Why Reductionism is not Eliminativism

As a student of Cognitive Science, I am primarily concerned with the nature of consciousness and the mind. Like many in my field, I am a physicalist – consciousness, emotions, and other mental states can be reduced to purely physical phenomena which can, in principle, be observed and studied like any other natural occurrence. This stands opposed to the dualistic belief that mental phenomena are of an entirely different kind – perhaps the result of some immaterial “soul” or “human spirit” which is not governed by physical principles and perhaps cannot even be understood by scientific methods. (I have briefly explained elsewhere why I judge this position to be entirely incoherent, as opposed to just unconvincing. A refutation of Dualism is not the purpose of this piece.)


A common fear that I encounter when explaining this physicalist position to others is that reducing the richness of mental experience to physical interactions, we destroy the “special quality” these experiences have. “If things like love, beauty and music are reducible to physical interactions of inert particles, what a bleak world that would be!” My knee-jerk reaction to this objection is “What does it matter?” The truth of a given empirical claim has nothing to do with how you feel about it (the fact that you might consider a leprechaun-based explanation of rainbows to be more beautiful than the optical/physical explanation does not contribute one whit to the veracity of the former). But ultimately this response is just me being cantankerous – I can understand the fear one might feel at the spectre of a inert, meaningless particle-world, and ultimately my commitment to physicalism is not based solely on hard-headed empiricism, but also because it is my experience that human-level phenomena such as love, beauty and music are not eliminated by a reductionist, physicalist world-view, and can, in fact, be enhanced therein.

So how can we begin to allay the fears of those who feel that by seeking to understand the mind we are destroying beauty? I think these fears come in two major flavours, the first being that by studying a thing we remove the mystery or beauty from the thing. I will assume that readers of Terry have an appreciation for the joy of intellectual pursuit, and will therefore not spend much time on this objection, but it is worth a mention all the same. First of all, the claim that by understanding a phenomenon of something at the physical level we eliminate its beauty seems to me entirely unsubstantiated even in common experience. If that were the case that understanding (in the “Erklärung” sense) meant destruction of the wonder one felt at the phenomenon itself, we should expect that those individuals who know the most about a given subject would eventually become the least attached to it. Of course, quite the opposite is true! How many biologists lose their sense of wonder at the beauty of nature once they understand the “merely” physical processes which underlie it? Those who study music theory and know the mechanics and rules which helped Mozart structure his Requiem might be expected to lose interest once these details were understood, but of course this is not the case. As someone who has studied Computer Science I can tell you that my love of computers is far greater now that I understand how they work than back in the days when I viewed them as mystical magic-boxes (I’ll spare you the details of how excited I got when I first understood how physical interactions in transistors could give rise to higher-level logic!) Clearly, understanding how something can be reduced to physical interactions does not eliminate our sense of wonder at the higher-level epiphenomenon.

The second, and more nuanced version of the fear of reductionism is the claim that once we admit that all mental phenomenon are the result of physical interactions, human-level truths lose all meaning. If everything is just the result of the physical interactions of inert particles, how can it make any sense to talk about ethics or beauty or love? Do free will and personal responsibility for one’s actions disappear if we understand ourselves as “merely” physical phenomena? Do ethics or feelings disappear?

It is my claim that this line of reasoning is the result of an unnecessary conflation of reductionistic physicalism (which I support) with eliminativism (which I do not), and a confusion of the levels of analysis at which we view different phenomena. Simply because we can reduce human-level phenomena to physical interactions does not mean we eliminate those phenomena, or render them meaningless.

To illustrate this point by way of analogy, consider the act of composing a sentence. To do so, you must put words together in a certain way, governed by the rules of grammar. One such rule (at least in standard modern English) might be “An adjective must be placed before the noun it modifies”. For example it is grammatical to say “The green ball is over there”, but not “The ball green is over there” (there may be exceptions to this rule but this is not important in the context of this discussion). Here, then, is a rule that is formulated at the level of words (or actually one level higher – the level of Parts of Speech). But notice that words are composed of letters (at least in English) – that is to say a word can be reduced to a collection of letters organized in a certain pattern. But if we now try to formulate our grammatical rule at the level of letters we run into trouble. How can we formulate this rule which holds for nouns and adjectives into one expressible at the level of letters? To do so would be very difficult, and would require that we already had a complete set of rules specifying how letters clump together to form words, and how these words are classified into Parts of Speech. But this does not invalidate the fact that words are a collection of letters, or prove that Parts of Speech somehow possess some ethereal, non-physical property, but merely that it becomes conceptually very difficult to apply a POS-level rule at the level of letters! There are rules and phenomena which are best understood at higher-levels of evaluation, where underlying complexities are grouped together into higher level categories, but this does not suggest that these phenomena are irreducible, merely that they are complex.

Those with any familiarity with Computer Science will be well very familiar with the kinds of levels I am talking about – although we might talk about Objects or Classes at the high-level programming strata, we know that these can be reduced to machine-code, and ultimately to the physical interactions of circuits and transistors. We would of course not expect to find Objects manifested at the physical level precisely because they are epiphenomena of a higher level of abstraction. We of course could in principle explain Object-oriented principles in terms of physical interactions but such an explanation would be far too complex for anyone to understand.

So it is that the reductionism of physicalism does not entail eliminativism with respect to mental phenomenon or human-level truths. Just because we can reduce conciousness to physical interactions does not eliminate it as a phenomenon in its own right, one governed by its own principles. These principles come into play at a level conceptually abstract from the physical, but still reducible. We should of course not expect to find love or ethics at the level of particles, because this is not the level at which they are manifest – but that does not entail that they have been eliminated. It may be true that your actions are governed by physical laws, which would seem to render free-will an illusion. But of course this defence will not stand up in court, because here at the level of conciousness you have a choice.

What, then, is there to be afraid of? If we can explain love in terms of physical interactions, will that change how it feels? Will understanding the neurological effect of music on our brains change the fact that it makes us want to dance? Of course not! We know that consciousness exists and feels a certain way to us – explaining it in terms of physical interactions will not change that.

To paraphrase Edward Slingerland in a presentation given last year – Just because one might know that love for ones children is the result of chemical and ultimately physical interactions in their brain, does not make that love any less real or potent. Seeking to understand the mind as we seek to understand anything else will not destroy any of its beauty. The word “mere” is a red-herring. Consciousness is a physical process – but what a remarkable and wondrous physical process it is!

(image taken by the author at Kitsilano Beach)

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Nicholas is a senior undergraduate majoring in Cognitive Systems (Computational Intelligence stream). He enjoys a wide spectrum of intellectual pursuits from programming to philosophizing. As well as writing for the Terry project, he maintains a private blog, and a personal home page. His long-term goals include earning his Ph.D, and crushing all life beneath the iron-clad heel of his merciless robotic cohort.