What Mary Learned: Putting the Knowledge Back in the Knowledge Argument

It amazes me that the Knowledge Argument is still kicking around to this day, and, according to the Stanford Encyclopaedia of Philosophy, “it is one of the most discussed arguments against physicalism.” Although, as we all know, being the “most discussed” is a poor indicator of being “the most convincing”. If anything, the more discussed, the more problematic.

But what I find the more remarkable is that the KA is still taken as an argument against physicalism rather than an argument against a particular conception of knowledge. It is the “knowledge argument” after all; knowledge plays a pivotal role in coming to the conclusion that physicalism is false.

What I’d like to do here is present a very quick criticism of the KA by appealing to an alternate conception of knowledge, one that allows for physicalism.

First, the KA. For those unfamiliar, it goes a little something like this:

MARY is confined to a black-and-white room, is educated through black-and-white books and through lectures relayed on black-and-white television. In this way she learns everything there is to know about the physical nature of the world. She knows all the physical facts about us and our environment, in a wide sense of ‘physical’ which includes everything in completed physics, chemistry, and neurophysiology, and all there is to know about the causal and relational facts consequent upon all this, including of course functional roles. If physicalism is true, she knows all there is to know. For to suppose otherwise is to suppose that there is more to know than every physical fact, and that is just what physicalism denies…

It seems, however, that Mary does not know all there is to know. For when she is let out of the black-and-white room or given a color television, she will learn what it is like to see something red, say. This is rightly described as learning—she will not say “ho, hum.” Hence, physicalism is false. (Jackson, 1986)

(1) Mary has all the physical information concerning human color vision before her release.(2) But there is some information about human color vision that she does not have before her release.

Therefore

(3) Not all information is physical information.

The weakness in the argument is in premise (1), that Mary has all the ‘physical information’ about colour before her release. And the key to this premise is this notion of ‘physical information’, often stated as ‘physical facts’. However, this assumes that all the ‘physical facts’, whatever they are, can be learned via books and television, i.e. that all one need to know everything is a sufficient number of propositions. I beg to differ.

Propositional knowledge is a handy thing, but facts aren’t the only game in town. This is the pivotal point that I believe is overlooked by many epistemologists. I hear there are some who believe that propositional knowledge is the only game in town, and that non-propositional knowledge is reducible to propositional knowledge. Hogwash.

I’ve outlined my arguments against this view on my old blog, but I’ll reiterate here. In short, it’s propositional knowledge that plays second fiddle to non-propositional knowledge. The textbook example is riding a bike. I can know how to ride a bike, yet be unable to recite all the propositional knowledge involved in that know-how (i.e. “I know that if I want to slow down by z km/h, I squeeze the brakes with n amount of force” or “I know that if I want to stay balanced, I need to correct my steering by y degrees when I tilt to the left by z degrees” etc.). Furthermore, it’s impossible for me to know all the propositions involved in riding a bike; there are just too many of them for me to know.

What constitutes my knowledge how? Simple: it’s dispositional. I know how to ride a bike if I can, in the right circumstances, indeed, ride a bike. I know how to do 10 push ups if I can, in the right circumstances, indeed, do 10 push ups. I don’t know how to do 1,000 push ups if I can’t, in the right circumstances, indeed, do 1,000 push ups.

By necessity, propositional knowledge abstracts away some rarefied aspect of this non-propositional knowledge, such as by describing a particular instance or by making a generalisation – but I’d contest that you’d need an infinite number of propositions to capture even a simple case of knowledge how, such as riding a bike.

Case in point: give someone a comprehensive manual on how to ride a bike. Have them study it in detail, until they can recite each sentence by heart. Then stick them on a bike and see if they know how to ride. Then pick them up and apply plasters.

Think of it this way: non-propositional knowledge is analogue; propositional knowledge is digital. A single analogue waveform can never be captured in perfect detail by a digital data. The resolution can improve indefinitely, but it’ll still fall short of capturing the nuance of the analogue waveform. Even a formula describing a waveform won’t capture the exact waveform as it appears in the world.

Furthermore, there’s some propositional knowledge that an individual can’t learn unless they have the non-propositional knowledge first. Like riding a bike. Even with a detailed (non-infinite) list of propositions about riding a bike, there’ll still be more new propositions that can be abstracted once you actually get on and ride it (“I know that if I want to slow down by 34.76904 km/h, I squeeze the brakes with n+17.44892 amount of force”).

So, back to Mary. I’d suggest there is some propositional knowledge that Mary cannot learn from books and televisions alone. Those books and televisions might as well tell her a long list of propositions about how to ride a bike, make a tricky putt or bake a soufflé. But until she actually experiences these things, the propositions will only be the barest approximation of the complete knowledge how. Same with seeing red.

Moreover, if we extend the thought experiment somewhat, say Mary has a twin, Mariam. Mariam is raised in an identical room to Mary, except, Mariam is shown a single red object once her ‘education’ is complete. Mariam has her ‘aha’ moment when seeing red, and then undergoes an advanced brain scan.

The precise state of her brain is then compared with that of black-and-white Mary. Mary then undergoes advanced neurosurgery, altering her brain to be identical with Mariam’s. When Mary awakens, do we expect that she will know what red looks like?

If epistemologists would just stop fixating on propositional knowledge like it’s the be all and end all, we might make some progress on these questions. It’s not like epistemologists are in such a strong state of agreement that current theories are looking unassailable. If we reconsider our reliance on propositional knowledge – and the insistence on drawing a hard distinction between the mind and the world around it – then we might resolve many problems in metaphysics, including the Knowledge Argument.