Fred, Mary, And A Tomato…

“No sane person should believe that something is subjective merely because it cannot be settled beyond controversy.” ― Hilary Putnam

As I type these words I experience the sensation of my finger pads pressing down upon my keyboard while the hypnotic ticking from my array of clocks representing different time zones vacillates between my conscious and unconscious awareness. What exactly is going on? How can we make sense of the subjectivity of this rich inner life of sounds and tastes and smells, including the admittedly drab phenomenal state that I opened with? How is it that we can all understand what we mean when we are talking about consciousness and yet, upon reflection, continuously fail to describe, with any certainty, the phenomenon of which we are all so intimately familiar? These subjective mental states that are likely only accessible upon introspection are referred to as qualitative state or qualia. While there is some debate over the various uses of the term qualia, for purposes of this paper, it will be used to describe the way in which it is something to be like something.

In his seminal essay “Epiphenomenal Qualia” Frank Jackson opens with a concession to the physical, chemical and biological sciences ostensibly recognizing the value of their contributions with respect to the information provided about ourselves and the world in which we live. This seemingly innocuous statement primes the reader to accept the view he intends to champion, however, before we can go through his argument I must first introduce the concept he intends to belie.

Ever since Descartes proclaimed “Cogito, ergo sum” — or in his native tongue “je pense, donc je suis” — western philosophy has, by most accounts, secured its epistemological foundation against radical skepticism while unwittingly presenting an empirical question for which we have yet to find any satisfactory evidence in either direction. Plato was perhaps the first to address what we now refer to as the mind-body problem in “The Phaedo” arguing that the soul exists separately from the body. This idea that an entity or non-physical substance exists separately from the body is what is known as dualism. On the other end of the spectrum, the view that is arguably more prevalent¹ today is referred to as physicalism. Technically, in order to maintain consistency, physicalism is a type of monism which is, unsurprisingly, the antithesis of dualism. Physicalism is the metaphysical thesis that everything is physical or that everything supervenes on the physical (Stoljiar 2017). Which essentially means that the mind may be reduced to the physical process of the brain.

Frank Jackson, the self-proclaimed “qualia freak,” asserts that “there are certain features of the bodily sensations, especially, but also of certain perceptual experiences, which no amount of purely physical information includes” (Jackson 1982, p.127)⁠. What he is saying is that irrespective of how much physical information one may have they will still fail to describe in any meaningful way the “hurtfulness of pains, the itchiness of itches, [or] the pangs of jealousy” (Jackson 1982, p.127). In other words, no amount of physical knowledge or information can elucidate what it is like to experience whatever sensation one is currently feeling. Therefore, he proclaims, physicalism is false.

While this may serve as a convincing intuition pump² even Jackson agrees that much more needs to be said in order to convince those wayward materialists. It is within this dialectic, which Jackson refers to as “the Knowledge argument,” that he sets out to demonstrate the non-physical nature of mental states. The knowledge argument comes in two iterations with Mary the colour scientist being the stronger case in my view but I shall briefly explain them both beginning with Fred.

He begins by asking us to imagine a world in which people “vary considerably in their ability to discriminate colours” (Jackson 1982, p.128). In the process of observing and recording the different variations the experimenters come across Fred who has better colour vision than anyone else on record. His vision is unique in that where we might just see a ripe tomato or the colour red — Fred see’s two distinct colours which he calls red1 and red2. Fred doesn’t just see two different shades of red, to him, “red1 and red2 are as different from each other and all the other colours as yellow is from blue” (Jackson 1982, p.128). Soon we come to find that Fred’s “optical system is able to separate out two groups of wavelengths in the red spectrum as sharply as we are able to sort out yellow from blue” (Jackson 1982, pp.128–129). Even still, Fred has tried to teach other people the difference between red1 and red2 but has been unsuccessful. This leads Jackson to conclude that, under these circumstances, no amount of physical information about Fred can tell us what kind of experience he is having whilst gazing upon the oddly coloured tomatoes.

Similarly, in another, much less vivid universe resides Mary. Mary is a scientist who specializes in the neurophysiology of vision and for reasons that aren’t particularly clear she has been forced to live and study the world from a black and white room whereupon she lives her life completely devoid of any colour whatsoever. Jackson makes it clear that Mary knows everything physical there is to know about colour and the ways in which people come to experience it. Now suppose that upon completing her studies and getting her black and white certificate³ for knowing everything physical there is to know about vision her captors decide to release her into the wild and colourful world in order to find out, once and for all, whether or not Physicalism leaves something out.

This is where Jackson’s argument becomes a bit precarious. He asks us what will happen when she is released. Will she learn anything new or not? Jackson certainly feels as though he has made his case, exclaiming, “it seems just obvious that she will learn something about the world and our visual experience of it” (Jackson 1982, p.130). So if in fact it is obvious that she will learn something new in spite of having all the physical information — Physicalism is false.

Consequently, many prominent philosophers have contributed to Jackson’s fame and curriculum vitae by presenting paper upon paper refuting or applauding his claims. However, I will limit my discussion to Daniel Dennett’s response from his paper entitled “”Epiphenomenal” Qualia?”. Dennett begins by capitalizing on Jackson’s premise that “She has all the physical information” (Dennett 1991, p.399). Dennett is convinced that the way in which Jackson has formulated his thought experiment leads “not just the uninitiated, but the shrewdest, most battle-hardened philosophers” (Dennett 1991, p.399) to falsely accept his proposition based largely upon their lack of imagination.

He then proceeds, in an effort to demystify Jackson’s illusory premise, to extend the thought experiment in even greater detail while still maintaining fidelity to Jackson’s claim. He introduces Mary to the world of colour in a similar manner only this time her captors present her with a blue banana. Now everyone, including Mary, knows that bananas are yellow, however, Jackson would argue, Mary has no way of knowing if the banana is blue or yellow because she has never experienced colour or the qualia involved with seeing colour. Au contraire, Dennett argues that by dint of her having complete knowledge — which is inconceivable to any reader in this century — protects her from falling victim to her incontestably demented captors. She is able to do this by “[writing] down, in exquisite detail, exactly what physical impression a yellow or a blue object would make on [her] nervous system. [She] already knew exactly what thoughts [she] would have (because, after all, the “mere disposition” to think about this or that is not one of [Jackson’s] famous qualia, is it?)” (Dennett 1992, pp.399–400).

Some would argue, and many have, that “Dennett’s implication that Mary could, through physical knowledge, acquire the ability for direct recognition of colours is mistaken” (H. Robinson 1993, p.175)⁠. Whereas I would contend that given our inability to say with any confidence in either direction and taking the history of scientific discovery into account, discounting the possibility given the scope of her alleged total knowledge seems a bit imprudent. Nonetheless, as Robinson notes, direct recognition or not, Mary’s knowledge would grant her the capacity to know “how someone is disposed to react, verbally or otherwise” (Robinson 1993, p.176) when presented with a particular colour stimulus.

This assertion aligns with Dennett’s contention regarding Jackson’s usage of the term “epiphenomenal.” On Jackson’s account, epiphenomenalists are comfortable stating that “Qualia cause nothing physical but are caused by something physical” (Jackson 1982, p.134). Which is to say that with or without Jackson’s qualia things would happen exactly the same with no way of empirically measuring its presence. His argument from the behaviour of others to the qualia of others seems to me to be an unintentional Gettier-case not to mention an exhaustive exercise of semantical acrobatics in order to defend his original claim.

As it happens, Jackson was unable to maintain his position and in a brief “Postscript on Qualia” (1998) he stated his reasons for “thinking that the “sensory side of our psychology, as it is constituted in our world” can be deduced, in principle, from knowledge of the physical nature of the world” (W. Robinson 2002, p.277)⁠. While assessing his arguments I was unaware of his retraction, nevertheless, with or without his “apostasy,” given my predilection towards materialism, I found his argument to be rather unconvincing. Now one could consider this an act of motivated reasoning on my behalf and surely that must be a factor, however, based on Dennett’s reasoning alone I am comfortable stating that Jackson based his entire argument on faulty premises. Additionally, by framing his position as one that must be true he, much like Descartes, commits himself to an unfalsifiable and in his own words inconsequential position.

Dennett concludes his essay admitting that despite his inability to prove that epiphenomenal conscious states don’t exist he can “show that there is no respectable motivation for believing in [them]”(Dennett 1991, p. 406)⁠. Which leads one to ask the epiphenomenalist, considering qualia’s lack of utility, cui bono? Jackson’s bottom line for defending epiphenomenalism with such vigor still perplexes me but at any rate, positive claims regarding the immaterial deserve the heavy-handed criticism that they are so often subjected to, especially when their advocates admit that their position has no effect on the physical world.