As I noted earlier this week, neuroscientist Christof Koch, who is chief scientist and president of the Allen Institute for Brain Science, seems to be having second thoughts about a purely physical view of consciousness. Koch has long been a proponent of a physicalist understanding of the mind-brain relationship—that the mind is in some sense reducible to the brain. He has proposed that consciousness arises as a product of brain-network complexity.

But when he was interviewed a month ago on Robert Lawrence Kuhn’s show Closer to Truth, he seemed to be reconsidering his physicalist perspective on the mind-brain relationship. He noted that experience—the first-person subjective character of consciousness—cannot be derived from matter by any mechanism we currently understand. He seems open to other explanations.

That’s very good! But he does, unfortunately, continue to invoke ways of understanding the mind that don’t make sense.

The fallacy of ascribing to the part what belongs only to the whole

Most significant is Koch’s statement in the interview:

[No physical things] have subjective experiences but brains do. [2:43]

In this statement, he has invoked the mereological fallacy. That is the fallacy of ascribing to a part (e.g., the brain) what can only be ascribed to the whole (e.g., the person).

For example, it is a fallacy to say that my feet walk or my eyes see. The reality is that I walk and I see, using my feet and my eyes.

The mereological fallacy is the most common and pernicious error in neuroscience. The brain does not perceive, think, feel, or desire. A person does these things. The brain does a lot of things—it metabolizes, it uses glucose and oxygen and produces carbon dioxide and water, it generates action potentials and secretes neurotransmitters, etc. These are physiologically very important and are generally necessary for many activities of the mind. But brains do not have experiences. People do.

Of course, one might say that Koch was merely using a metaphor, as we all do at times. We say “my eyes are tired” or “my heart yearns for home”. Metaphors are fine, as long as we keep in mind that they are metaphors. But in neuroscience, metaphors are the basis for research programs.

The binding problem as an example of the fallacy

For example, for a century, neuroscientists have struggled with the binding problem. That’s the name that neuroscientists give to the difficulty of trying to explain how distinct brain modules give rise to coherent thought. They ask how it is that “images” of various perceptions in the brain—e.g., the sun, the beach, a beach chair, the ocean—are “bound together” to yield the unitary thought “I’m at the beach.” How are perceptions put together to form a simple thought? How does the brain integrate what it sees, hears, feels, tastes and smells into a unified thought?

The error here is that, in thinking of the mind in this way, neuroscientists fall victim to the mereological fallacy. The brain does not see, hear, feel, taste, or smell. It is the person who sees, hears, feels, tastes, and smells. The modular parts of the brain are indeed necessary for ordinary perceptions. But the perceptions belong to the person, not to the organ inside the skull.

When understood in this way, the binding problem disappears, because there is no difficulty understanding how a person—a unified whole human being—has a unified experience, any more than it is difficult to understand how a person watching the Superbowl can understand what is happening in the game when he is watching 22 individual players on the field.

A person is a unified whole, and the experience a person has is unified is well, even though the organ of perception (i.e., the brain) is modular.

It is very good that Dr. Koch is moving away from the physicalist bias that benights modern neuroscience. It would also be good for him to toss off the logical fallacies—like the mereological fallacy—that are the hallmark of physicalism and lead neuroscientists astray.

You may also wish to read: Leading neuroscientist wavers on physical view of consciousness. On Closer to Truth, Christof Koch said last month, “Consciousness cannot be explained only within the framework of space and time and energy, but we need to postulate something additional.” It’s not that we have the wrong philosophy or experiments. It’s that we can describe what we understand better than the means by which we understand.