This book is a collection of papers on the topic of phenomenal consciousness, posing and answering the Mary-the-brilliant-neuroscientist-in-a-black-and-white-room thought experiment. This thought experiment was first published by Frank Jackson in his article "Epiphenomenal Qualia" (1982). Since then, many objections and objections on the objections have been published, so much so that Frank Jackson himself turned against his creation. 

The idea of the thought experiment is the following: Mary grew up in the black-and-white room; her clothes are black, and she herself is painted white. Mary has a TV and the internet, which are also filtered with a black-and-white filter. This doesn’t stop Mary from becoming the world’s best neuroscientist. Her field of study is human vision. She knows all the physical facts that there are to know about the visual system, and she knows what happens when other people see colours. However, she had never seen any colour except for black and white herself. One day, she is finally released from her captivity. She sees colours for the first time. The question is: does Mary learn anything new—any new facts—when she experiences the colour from the first-person point of view? 

In a formal way, this argument, also known as the ‘Knowledge argument’, can be put as follows:
1. Mary knows all the physical facts about vision.
2. Mary learns a new fact or new information after her release.
hence
3. Not all information is physical, and physicalism is false. 

Mary’s knowledge argument, therefore, is an argument against physicalism. The book contains several essays by physicalists rejecting the argument. The first avenue is to reject the idea that Mary learns a new fact or new information. In particular, the argument by D. Lewis was clear to me. He notes that if information is lacking, there would be two or more alternatives. If I lack information about my grade on the exam, there could be several possible grades. Then, when information is gained, the ambiguity is resolved. When I get my paper graded, I now know the grade. However,in the case of Mary, this logic doesn’t follow. There are no conflicting possibilities. Hence, no information is gained. According to Lewis, Mary gains the ability—namely, the ability to remember, imagine, and recognise. This view is called the ‘Ability Hypothesis’. 

The second avenue is the ‘Acquaintance Hypothesis’, proposed by E. Conee. Under this view, Mary had become acquainted with phenomenal quality by noticing it in sensory experience. In other words, the most direct way to grasp a quality is through experience. This view is a bit vague, in my impression. Also vague, but slightly different from the second route, is the idea that Mary learns old facts in a new way. The fourth attempt to save physicalism is to deny that Mary knew all the physical facts. This position is taken by non-reductive physicalists. They claim that there are subjective facts that are physically realised. Therefore, Mary could not have known all the facts. 

On the opposite side, there are cautious arguments against. I would not say against physicalism, but rather simply against the arguments against Mary’s argument. Here, I like M. Nida-Rümelin's thought experiment. He introduces the case of Mariana, who is similar to Mary; she is in the black-and-white room and knows something about colours. Additionally, she participates in an experiment, during which she is shown four colours and is asked which one is the colour that normal people see when they look at the sky. Mariana also thinks that the sky is beautiful, so she picks out colour red. Now she has conflicting beliefs. 1) She believes nonphenomenally that the sky is blue to normal people; 2) she doesn't believe nonphenomenally that the sky is red to normal people; 3) she believes phenomenally that the sky is red to normal people; 4) she doesn't believe phenomenally that the sky is blue to normal people. This hypothetical case demonstrates that phenomenal and nonphenomenal beliefs may differ.

Lastly, an interesting point was expressed by P.M. Churchland. While seemingly refuting physicalism, Mary’s case also refutes substance dualism. If Mary knows all the ‘ectoplasm’ truths there are, upon her release, she will learn something else. Such that, in the argument, physical truths can be substituted by ectoplasm truths, and hence, substance dualism is refuted. 

The book sometimes becomes fairly technical, but overall it is a great piece to get yourself acquainted with the knowledge argument and arguments against it. I cannot say that I am convinced by most of the arguments against it, but I see that, while intuitive at first glance, Mary’s argument holds caveats and ambiguities. Something to think about. 

December, 2023