One cannot learn what it is like to subjectively experience something without actually experiencing it

Frank Jackson’s Knowledge Argument1

  • Mary is confined to a black-and-white room, is educated through black-and-white books and through lectures relayed on black-and-white TV. Through this, she learns everything there is to know about the physical nature of the world, including 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.
  • Yet, if Mary is let out of her black-and-white room or given a colour TV, she will learn what it is like to see something red.

The implication here is that Mary cannot learn what it is like to subjectively experience red from reading physical facts (similar argument re: semantics in Chinese room argument).

Dennett’s Refutation of the Knowledge Argument1

“And so, one day, Mary’s captors decided it was time for her to see colours. As a trick, they prepared a bright blue banana to present as her first colour experience ever. Mary took one look at it and said ‘Hey! You tried to trick me! Bananas are yellow but this one is blue!’ Her captors were dumbfounded. How did she do it? ‘Simple,’ she replied. ‘You have to remember that I know everything—absolutely everything— that could ever be known about the physical causes and effects of colour vision.

  • No double transduction
    • Transduction is a conversion of one for another
    • Peripheral/internal transducers are sense organs (e.g. eyes) that transform physically detectable properties to electrochemical signals
    • There is no further conversion of neural signals into a qualitative medium
  • No Cartesian theatre in the brain
    • There is no central place where all things ‘come together’ and consciousness happens
    • Point of view of the observer is smeared over a large volume of the brain with different networks (distributed model of representation)
  • Consciousness is like fame
    • “Just as becoming famous is not a precisely datable event like being transduced into a medium (like being televised), so achieving consciousness in the brain is not a precisely datable transition in the brain.
  • No qualia if intrinsic properties are instantiated by rather than represented by neural activity


Critically evaluate Frank Jackson’s “Knowledge Argument.” Does Mary learn something new, and if so, what exactly does she learn and what are the implications for physicalism? If she does not learn anything new, explain how and why this is the case.

In this paper, I posit that Frank Jackson’s “Knowledge Argument” is logically sound but hinges on many bold and often presumptuous premises to be true. As such, the conclusion should not be taken for granted without more clarifications around premises and terminology.

I propose that Mary has all of the ‘know-that’ knowledge but none of ‘know-how’ knowledge. The act of Mary ‘seeing’ colour for the first time means that she learns new ‘know-how’ knowledge which she did not have. Physicalism, as a result, is preserved as Mary only has ‘know-that’ knowledge so does not know all physical facts about colour perception.

This relies on three facts:

  1. There is a distinction between physical fact and physical knowledge
  2. There are unknowable physical facts that give rise to new experiences
  3. Know-how cannot be learned through know-that (e.g. reading and watching videos)

Briefly, the conclusion that Frank Jackson posits is as follows:

  1. It is possible for someone to know all physical information there is to know about , still experiencing the act of seeing colour will teach her something about .
  2. Certain experiences (e.g. experiencing colour) still teach Mary something new. Then, this means that all physical information there is to know about do not completely describe all information about .
  3. This contradicts the theory of physicalism: that everything, including mental states, has a physical explanation. Extending this argument: if we could know every physical detail about someone else’s brain, one would still not understand what it is like to experience things for them (Nagel’s Bat Argument).

However, this conclusion relies heavily on the first premise being true, that is, it being possible for one to “acquire … all the physical information there is to obtain about what goes on when we see []”. Let us first examine the explicit distinction between ‘physical knowledge’ and ‘physical facts’ here.

Knowledge, specifically, entails all ‘knowable’ things. In the context of this paper, I define ‘knowledge’ as justified true belief. Subject knows if and only if1:

  1. is true
  2. believes that
  3. is justified in believing that .

I posit that there are facts (read true statements about object ) that cannot be known, let alone proven. For example, let us imagine that it is a fact that aliens do not exist. As of now, we have no suitable methodology or measurements that would allow us to confirm this fact (this would involve an exhaustive search of the universe which, as far as we know, is impossible). Thus, the set of all true statements about object is equal to or larger than the set of all obtainable knowledge about . To know all physical knowledge about then does not necessarily imply knowing all physical facts about something.

Specifically, we note that the original Mary’s Room argument phrases knowing as knowing “all the physical information there is to obtain about what goes on when we see []” (emphasis added). Then, there may be some physical facts Mary may not know that contribute to her experience of experiencing ‘yellowness’ when seeing a banana for the first time that she may not have known ahead of time, despite her having complete physical knowledge of the banana. As a result, Mary experiences something new (namely, seeing yellow) but does not learn anything new.

The sharp-eyed may note that the previous argument relies on the fact that the set of all true statements about object is explicitly larger than the set of all obtainable knowledge about . However, the statement originally assumed that the set of all true statements is larger than or equal to the set of all obtainable knowledge. This exposes an edge case which could be problematic where the set of all true statements is exactly equal to the set of all obtainable knowledge (i.e. subject knows all obtainable knowledge about , which coincidentally is also the set of all true statements about ).

I will show how this does not prove to be a problem for our argument. I raise one main question: Why is it obvious that she will learn something new about the world through an experience?

To be explicit, let us examine the framing of the Mary’s room2:

  • An epistemic subject A appears to have no access to particular items of knowledge about a subject B
  • A cannot know that B has an experience of a particular quality Q on certain occasions
  • This particular item of knowledge about B is inaccessible to A because A never had experiences of Q herself

This is quite similar to Thomas Nagel’s Bat Argument3. Despite everything that Mary knows about seeing colour, she doesn’t know what it is like to see colour.

Specifically, the Knowledge Argument relies on knowledge that is explicit or codified and can be communicated via language. I argue that, conceptually, one cannot ‘know’ all there is to know about seeing colour through purely linguistically communicated language. I refer to this ‘linguistically unknowable’ knowledge as tacit knowledge.

We first examine three different kinds of knowledge4:

  1. Acquaintance knowledge: we get to know the characters of others (like friends) by being around them. This is a form of tacit knowledge.
  2. Knowledge-that: propositional knowledge, facts about the world obtained through reading, talking, and consuming content. This can be linguistically communicated.
  3. Knowledge-how: truly knowing how to do something, speaking, reading, etc. This is a form of tacit knowledge.

My position is that knowledge-how cannot be learned through only knowledge-that. Ryle calls this the Sufficiency Argument: “how could propositional knowledge be sufficient for knowing how to do something?”5

From this list above, knowledge-that is the only form of transferrable or communicable knowledge. Knowledge-how is a form of tacit knowledge which is inexpressible via language. Knowledge-how, by definition, is only acquired through practical experience in the relevant context. To attempt to reconstruct knowledge-how using knowledge-that is to build a potemkin village, a sort of ‘facade’ of understanding. One can read all about playing a piano — the music theory, the muscles to actuate, the feel of the keys — yet fail to actually play the piano. Learning to play piano requires an embodied experience of feeling the keys and wiring the feedback between the concept of music in your brain to the motion of playing the notes.

Thus, in Frank Jackson’s Knowledge Argument, Mary has all the ‘know-that’ knowledge about the perception of colour but none of ‘know-how’ knowledge. The argument depends heavily on Physicalism stating that Mary knows all physical facts about any given object. I have shown through this paper that the premises of Jackson’s argument is dubious at best, namely the ability for Mary to know all physical facts about . Thus, Physicalism is preserved.


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  5. Knowing How and Knowing That: The Presidential Address, Ryle 1946