Tufan Kıymaz is an Assistant Professor at Bilkent University. His primary research topic is the nature of phenomenal knowledge. He is also interested in philosophy of well-being, especially the modern applications of Stoic ethics.
A post by Tufan Kıymaz.
Mary is a super-scientist who knows all facts about human visual experience that are expressible in physical/functional terms; however, she has never seen colors since she lives in a black-and-white room. If physicalism is true, then her physical/functional knowledge is complete knowledge about human visual experience. One day, she leaves the room, sees a red tomato and exclaims “So, this is what it is like to see red!” She learned a new fact, which means that her physical/functional knowledge was not complete knowledge, and therefore physicalism is false. This is Frank Jackson’s (1982, 1986) knowledge argument against physicalism.
Some philosophers, such as Churchland (1985:25), Maloney (1985:36), and Dennett (2007), interpret this argument to be about Mary’s inability to imagine red while she was in the room. However, Jackson writes:
the knowledge argument claims that Mary would not know what the relevant experience is like. What she could imagine is another matter. (Jackson 1986: 295, also see 292)
Jackson’s following remarks about Fred, who has a color experience that we do not have, makes it clear that his knowledge argument is not about imagination:
If Physicalism were true, enough physical information about Fred would obviate any need to extrapolate or to perform special feats of imagination or understanding in order to know all about his special color experience. The information would already be in our possession. But it clearly isn’t. (Jackson 1982:132, emphasis in the original)
So, the interpretation of his argument by the objectors, which states that Mary’s inability to imagine what it is like to see red implies that physicalism is false, is a strawman. Let’s call this strawman “the imagination argument.” As far as I can see in the literature, the imagination argument is criticized and rejected but I have never seen an explicit defense of this argument. In my paper “What Gary Couldn’t Imagine” (2019), I presented the most powerful version of the imagination argument that I can think of and evaluated its strengths and weaknesses. I believe that the imagination argument deserves more attention than it has received so far.
Before I present my version of the argument, I need to introduce two terms.
1. Transitive ability: Ability A is a transitive ability iff
(i) A is a skill-based ability (not just a capacity),
(ii) Exercising A requires deliberately producing a token end product of type E,
(iii) We normally express A’s exercise using a transitive verb, whose direct object is E (or a generic token of E).
For example, playing the Moonlight Sonata on the piano, building a sandcastle, drawing a circle are transitive abilities (as opposed to, say, the ability to swim or the ability to lift a 50 kg rock). Imaginative ability (at least the kind involved in the imagination argument) is a transitive ability, where the end product is a mental image.
2. Product-Knowledge (PKnowledge): Based on (ii), exercising a transitive ability requires knowledge of the end product. If one doesn’t know what to produce, then one cannot deliberately produce it. PKnowledge can be propositional or nonpropositional. For example, you can describe someone’s face to a sketch artist and she can draw it based on your description. In this case, her PKnowledge is propositional. Or, one can draw a picture of a face by simply looking at the actual face, in which case the PKnowledge is nonpropositional.
Now, the imagination argument. I will use the name “Gary” to emphasize that this is a separate argument from Jackson’s argument. Gary is in exactly the same situation with Mary.
1. If physicalism is true, then Gary, before his release, has complete propositional PKnowledge of what a red tomato looks like.
2. If Gary, before his release, has complete propositional PKnowledge of what a red tomato looks like, then Gary, before his release, can imagine what a red tomato looks like.
3. Gary, before his release, cannot imagine what a red tomato looks like.
4. Therefore, physicalism is false.
The argument is valid. Let’s look at the premises one by one.
First premise: If there is nothing nonphysical about the phenomenology of what a red tomato looks like, then complete propositional PKnowledge of what a red tomato looks like can be expressed in physical/functional terms. So, if physicalism is true, then Gary’s complete physical/functional knowledge constitutes complete propositional PKnowledge (for his imaginative ability) of what a red tomato looks like.
Second Premise: If Gary, before his release, has complete propositional PKnowledge of what a red tomato looks like, then he knows what to imagine. Why wouldn’t he be able to imagine it, then? A red tomato is not in principle unimaginable for him. After all, like any normal person, he can easily imagine it once he sees it (based on nonpropositional PKnowledge). The general idea here is this: If S can produce x based on nonpropositional PKnowledge, then S can also produce x based on propositional PKnowledge (given that S has the cognitive capacity to understand and process that knowledge).
One might object: maybe there are exceptions to this. For example, let’s say I can sing a song when I hear it, but I cannot sing it based on the score sheet, even though I can read and understand it. Maybe, Gary’s situation is similar; maybe some things are only imaginable based on nonpropositional PKnowledge. But, I don’t think this analogy is successful. Gary, like us, can normally imagine physical properties of things, such as their shape, based on propositional PKnowledge, and, if there is nothing nonphysical about what a red tomato looks like, then why would it be an exception? Here is a better analogy. Suppose I can sing any song once I hear it, no exceptions. Also, I can sing every song by reading the score sheet, except for blues songs. But, what is special about the blues songs? Given that I have the capacity to read and understand every score sheet, I think the best explanation of my inability to sing blues songs based on their score sheets is that those score sheets are incomplete and they don’t provide me with sufficient information about what to sing.
Third Premise: Gary, before his release, cannot imagine what a red tomato looks like. Why would we accept this? Consider the following two claims:
(K) Mary cannot infer what it is like to see red from physical/functional information.
(I) Gary cannot imagine what a red tomato looks like based on physical/functional information.
(K) is essential for Jackson’s argument, however, he does not give a separate argument to defend (K). He writes that “it seems just obvious that she will learn something about the world and our visual experience of it” when she sees colors for the first time (1982: 130, my emphasis) and that “the knowledge argument is a valid argument from highly plausible, though admittedly not demonstrable, premises to the conclusion that physicalism is false” (1986: 295, my emphasis) where one of the premises is a version of (K).
(I) is also supposed to be intuitively acceptable (which also makes premise three acceptable)[i]. Intuitively, one can describe the shape of a tomato to someone (by, for example, giving the algebraic formula of a sphere) so that that person can imagine the shape, but can the color of a tomato be described to someone so that that person can imagine its color solely based on the description? Admittedly, my intuition for (I) is weaker than my intuition for (K), but, still, I find (I) acceptable. And, I am not alone. As far as I can see in the literature, a posteriori physicalists typically accept (I), since, typically, they accept that Mary has to experience red in order to acquire phenomenal knowledge of red (whether phenomenal knowledge consists in cognitive know-how, or acquaintance knowledge, or possession a phenomenal concepts).
But, if you don’t share this intuition, that’s okay. Even if the imagination argument is not ultimately successful, it still challenges the physicalist to do at least one of the following, which is, I think, enough to make the imagination argument worth thinking about:
(1) Accept that it is possible to imagine a phenomenal property (that is normally imaginable based on experience) solely based on physical/functional information (which means that Mary can learn what it is like to see red while she is in her room).
(2) Given that phenomenal properties are physical properties, explain why it is not possible to imagine a phenomenal property (that is normally imaginable based on phenomenal experience) based on complete propositional knowledge about that phenomenal property.
[i] Note that (I) is compatible with the second premise. (I) is about physical/functional knowledge, but the second premise is about propositional PKnowledge.
References:
Churchland, Paul M. (1985). Reduction, qualia and the direct introspection of brain states. Journal of Philosophy 82:8-28.
Dennett, Daniel C. (2007). “What RoboMary Knows.” In Alter, Torin, and Sven Walter (eds.) Phenomenal Concepts and Phenomenal Knowledge. Oxford University Press, 14-31
Jackson, Frank. (1982). “Epiphenomenal Qualia.” The Philosophical Quarterly 32: 127–36.
Jackson, Frank. (1986). “What Mary Didn’t Know.” The Journal of Philosophy 83(5): 291–95.
Kıymaz, T. (2019) “What Gary Couldn’t Imagine.” Journal of Philosophical Research. 44: 293-311
Maloney, J. Christopher. (1985). “About Being a Bat.” Australasian Journal of Philosophy 63(1): 26-49.