Peter Carruthers

Peter Carruthers is a professor of philosophy at the University of Maryland who specializes in philosophy of mind. He recently published a paper “The Illusion of Conscious Thought.”

At first glance, the title seems provocative and seemingly self-refuting. The very concept of an “illusion,” after all, presupposes that some kind of consciousness exists that is not an illusion, with the result that it can perceive an illusion. That aside, Carruthers has some important and true things to say about the mind. Here’s an excerpt from an interview with him by Steve Ayan at Scientific American (December 2018), with my commentary following:

Carruthers: I believe that the whole idea of conscious thought is an error… thoughts such as decisions and judgments should not be considered to be conscious. They are not accessible in working memory, nor are we directly aware of them. We merely have what I call “the illusion of immediacy” — the false impression that we know our thoughts directly… In ordinary life we are quite content to say things like “Oh, I just had a thought” or “I was thinking to myself.” By this we usually mean instances of inner speech or visual imagery, which are at the center of our stream of consciousness—the train of words and visual contents represented in our minds. I think that these trains are indeed conscious. In neurophilosophy, however, we refer to “thought” in a much more specific sense. In this view, thoughts include only nonsensory mental attitudes, such as judgments, decisions, intentions and goals. These are amodal, abstract events, meaning that they are not sensory experiences and are not tied to sensory experiences. Such thoughts never figure in working memory. They never become conscious. And we only ever know of them by interpreting what does become conscious, such as visual imagery and the words we hear ourselves say in our heads… I would rather say that consciousness is not what we generally think it is. It is not direct awareness of our inner world of thoughts and judgments but a highly inferential process that only gives us the impression of immediacy.

What does Carruthers mean by this? To begin, it is essential to clarify just what we mean by “consciousness.” What is it to be conscious? There are three kinds of things of which we can say we are conscious:

• Bodily feelings like pain, itch, cold, heat, and so on
• Moods — emotions such as fear or joy
• Objects, either physical objects (a tree or a person) or conceptual objects (mercy, justice, mathematical concepts, and the like).

Consciousness of bodily feelings and emotions are qualia, which are the subjective components of thought. Consciousness of objects — whether physical or conceptual — is called intentionality by philosophers. Intentionality is the ability of a thought to be directed toward an object. All consciousness of this sort is “about” something. Material things that merely exist lack intentionality. For example, my thought, while writing this post, is about philosophy of mind (intentional). The pen on my desk is merely a thing. It  is not “about” anything. We can say that it lacks inherent intentionality. Even consciousness of bodily feelings and emotions can be said to be intentional. (There is a debate about whether qualia are really a subset of intentionality but we will not pursue it here.)

I believe that the most satisfactory definition of consciousness is the intentional power of the mind — the ability of thought to be “about” something. Consciousness is always directed to an object, whether that object is physical, emotional, or conceptual. If there is no “aboutness,” there is no consciousness.

All intentionality entails two things: the process by which (1) we think about something, and the thing about which (2) we think. When I perceive a tree, I am perceiving (1) a tree (2). When I think about justice, I am contemplating (1) justice (2).

This understanding of the mind — that thought involves both that of which we think (2) and that by which we think (1) dates back to Aristotle (384–322 BCE). It was a cornerstone of Thomas Aquinas’s (1225–1274) philosophy of mind.

St. Thomas, following Aristotle, observed that it is only the objects of thought that we are aware of. We are never aware of the process of thought. Thus, sensation, perception, memory, judgment, understanding, etc., are unconscious processes. They are the processes by which we sense bodily feelings, perceive objects, remember faces, judge opinions, and understand concepts. But it is the feelings, objects, faces, opinions, and concepts themselves of which we are conscious. We are never conscious of the sensations, perceptions, etc., by which we are conscious of these objects.

We are most certainly conscious. The very term “illusion,” as noted earlier, presupposes consciousness. A doorstop, unlike a man, has no illusions. But we must keep in mind that we are conscious only of the objects of our thoughts, not of the processes by which we have those thoughts. We have a composite of unconscious and conscious mental powers, working in synchrony, each indispensable to the thought. There is “that which we think” and “that by which we think.” We are conscious only of the former, but the latter, which is unconscious, is just as essential to our thought.

Why bother, you might ask, with all of this conceptual gymnastics? Why split hairs? Why not just say that we are conscious of perceptions, understandings, etc.? Why make a distinction between the unconscious process of thought and the conscious object of thought? As it turns out, it is vitally important that we do so. The failure to do so has been a catastrophic philosophical mistake that plagues philosophy and neuroscience to this day.

The error of failing to make a distinction was introduced by the early modern philosophers, especially by John Locke (1632–1704) in his Essay Concerning Human Understanding (1689) and it has bedeviled neuroscience into modern times. The assertion that we are conscious of our perceptions and our conceptions rather than of the objects of our perceptions and conceptions leads inexorably to solipsism (nothing truly exists for me except my own consciousness). If we are only aware of the processes in our mind (or brain), and not of the actual objects to which our processes refer, then we can know nothing of reality outside of ourselves. Nothing.

John Locke (1632–1704)

That misunderstanding is the predicate for Immanuel Kant’s (1724–1804) misguided distinction between the noumenal (the thing in itself) and the phenomenal (the thing as it appears). This deadly misunderstanding, based on Locke’s fundamental error, pervades modern neuroscience. It is inferred or explicitly asserted that we are directly aware of brain processes, such as patterns of neuronal firing, etc. If that is true, then we are aware of no reality outside of ourselves. We have no choice, if we are rational and honest, but to be solipsists. This Lockean/Kantian metaphysics, the basis for much of our modern understanding of ourselves and the (“unknowable”) world, derives from the rudimentary confusion between the means and the objects of our consciousness.

Again, the truth is that we are aware of none of the processes by which we think, not in any primary way. We are aware only of the objects to which they point — to the tree or perhaps the concept that gives rise to the neuronal processes in our brain. Neurophysiology is that by which, not that which, we perceive and understand.

The objects of our understanding are physical and conceptual objects that are, literally and figuratively, realities which are outside of us. When we think, we think about reality, not about the neurological processes by which we connect to reality. It is by keeping this understanding clearly in mind that we escape the solipsism that bedevils modern neuroscience.

If, when he uses the term “consciousness,” Carruthers means (and I think he does) the processes of neurophysiology, etc. by which we apprehend reality, his provocative assertion that “consciousness is an illusion” is a genuine insight. It is an insight that dates to Aristotle, and it is a cornerstone of any genuine understanding of the mind and of any sane grasp of reality.

Michael Egnor is a neurosurgeon, professor of Neurological Surgery and Pediatrics and Director of Pediatric Neurosurgery, Neurological Surgery, Stonybrook School of Medicine

Also by Michael Egnor: Does Your Brain Construct Your Conscious Reality? Part I A reply to computational neuroscientist Anil Seth’s recent TED talk

and

Does Your Brain Construct Your Conscious Reality? Part II In a word, no. Your brain doesn’t “think”; YOU think, using your brain