How does a brain – a physical body organ – generate a mind? This essay addresses that basic philosophical question.
People have always wondered how the mind and body are related. Some ancient cultures placed the mind in the heart, others in the liver or spleen. Some thought the brain’s function was cooling the blood. But with the dawn of scientific medicine, the brain was recognized as the organ of the mind.
“And men ought to know that from the brain and the brain alone arise our pleasures, joys…griefs, and tears. Through it, in particular, we think, see, hear, and distinguish the ugly from the beautiful, the bad from the good.”
– Hippocrates, 4th century BC
So how are brain and mind related?
Classical philosophers debated this question for centuries. There were many schools of thought, many theories but, in the end, no way to prove or disprove any of them. Philosophers finally had to admit that logic alone could not fathom the answer to the mind-body question.
With that came the hope that science could find the answer, and neuroscience has indeed shed light on the subject. We have learned that brain electrical activity is intimately related to the mind. Every state of consciousness, every thought, feeling, perception, and urge to action involves brain electrical activity. When these electrical patterns are altered by drugs, electrical stimulation, injury, or in any other way, corresponding changes occur in mental processes. Neuroscience research overwhelmingly supports this basic notion.
So what is “brain electrical activity” and how is it related to the mind?
Every neuron is specialized to conduct electrical impulses – tiny bioelectric currents transmitted in milliseconds along the neural “wire.” The current is produced by the rapid flow of electrically charged atoms through the nerve cell’s membrane. Each neuron can fire several impulses per second, transmitting information coded in its firing patterns.
In addition to neural impulses, more subtle currents also flow within each neuron, produced by similar electrochemical processes. Together these various neural currents generate a tiny electromagnetic field, which radiates out around each cell. Every neuron generates a dynamic energy field, in constant flux, changing with the current as it flows along the cell.
Billions of neurons, functioning together in pathways and systems, generate much stronger electromagnetic fields. These “brainwaves” can be recorded, using electrodes placed on the scalp, by the electroencephalograph (EEG).
So neurons generate electrical currents and energy fields, which are intimately related to the mind. But how are they related? How is this physical brain energy related to mental energy or consciousness?
There’s no proof, but most neuroscientists think they are identical.
According to identity theory, brain energies and mind are two aspects of one thing. They are equally valid ways of perceiving the same reality. This view fits well with research findings from all neuroscience disciplines. Identity theory is by far the dominant philosophy among brain scientists today. It has been called “the central dogma of neuroscience.”
“In other words, if I see an apple, certain electrochemical events…occur in my brain, and these events have in addition to their physical character, another character [which is] the experience ‘seeing an apple’…It is easy to see why most neurophysiologists favor some version of the identity thesis…Technology has short-circuited centuries of philosophical speculation.”
– Physician-philosopher Anthony Campbell
But despite identity theory’s strengths and success, some people have misgivings –
Some would agree with the great psychologist William James, who noted the “somewhat ridiculous swagger” of “medical materialism,” and its tendency to devalue our inner nature. Sometimes it seems like science wants to ignore or analyze the spirit and magic out of our lives. We feel, James said,
“menaced and negated in the springs of our innermost life. Such cold-blooded assimilations threaten, we think, to undo our souls’ vital secrets…[and] explain away their significance.”
On first glance, identity theory strikes some people this way. Its physical- mental equivalence seems to hint at James’ “medical materialism,” threatening to reduce or confine our souls. But a closer look is reassuring. Identity theory actually fits quite well with the existence of magic, as we’ll see shortly.
But first, the picture comes into better focus with a quick look at the other philosophical schools. All possible answers to the mind-brain question fall logically into one (or a combination) of these categories:
Materialism – The basic reality is physical; mind is illusory or insignificant.
Idealism – The basic reality is mental; the physical world is an illusion.
Dualism – The physical and mental are both real and separate from each other.
Identity theory – The physical and mental are both real and identical, equally significant aspects of the same energy.
Each of these worldviews has, at various historical times and places, been a dominant school of philosophy. Even today, none of them can be proved or disproved, and each has its adherents.
Materialism says that your hopes and prayers are really just brain electrical patterns, with little or no meaning in themselves. If mind exists at all, it is an accidental byproduct, an insignificant “epiphenomenon” of brain energies. From ancient Greek philosophers to recent behaviorists, some have claimed that the basic reality is physical, and mind should not be taken seriously.
Idealism was a major school of eighteenth-century philosophy, which asserted that mind is the only reality. This theme is also central to some religions: the material world is maya, or illusion. The physical world, including our bodies, exists only as a pattern of images in the mind. Idealism usually posits a supreme perceiver, or God, in whose mind all reality is grounded. All of us and all our realities are dreams of the universal mind.
Dualism maintains that the physical and mental are both real and separate from each other. Brain energies and mind are different, but very closely related, always interacting and influencing each other. Dualism appeals to common sense – simple reflection does suggest that our minds are different from the physical world.
So how do the dualist mind and brain interact? The seventeenth-century philosopher Descartes located their interactions in the pineal body, a small brainstem region, and for some time afterward the pineal was considered “the seat of the soul.” Of course, there is no scientific evidence to support this – or to support any more recent dualistic theory.
If thoughts and feelings are separate from brain energies, and interact with them, they should produce some detectable influences on brain functions. Researchers have found no such influences, no evidence at all of separate mental functions. Today few neuroscientists are dualists. Most would say that the commonsense separation of “physical” and “mental” ignores extensive evidence that mind also has a physical aspect. They would point out that everything we know about the brain and mind is well accounted for by identity theory.
From a scientific perspective, identity theory best answers the mind-brain question.
So let’s look more closely at its implications. Within identity theory we find two major schools of thought –
Emergentism maintains that mind emerged, or first came into existence, at some stage of evolution when brains became complex enough. Today it is present only in brains with at least that degree of complexity. Lower animals, with smaller and simpler brains, are not conscious.
Panpsychism holds that all animals, even those with the simplest brains, have some consciousness. In fact, mind does not depend on brains at all. It has always been present, to some degree, in all matter and energy. Brains just amplify and elaborate what was always there.
Emergentism limits mind to complex brain energies, while panpsychism extends it to all physical energy. In emergentism, our individual minds are separate islands of consciousness. In panpsychism, they are interconnected expressions of universal consciousness.
Emergentism is a combination of identity theory (in complex brains) and materialism (everywhere else). Panpsychism is pure identity theory – in brains and everywhere else.
Looking first at emergentism, it claims that mind evolved by accident from mindless matter. At some threshold of neural complexity, mind emerged as a brain function – before that there was no mind. As one scientist put it, “there was a long time in the history of the world when it was free of consciousness.”
But at what evolutionary stage did consciousness emerge? Today which animals are conscious and which are not? Here we find all kinds of opinions –
Some attribute consciousness to human beings only. In this recently dominant view, mind requires language, is basically equivalent to thinking, and our cerebral cortex is the only brain region complex enough to generate it.
But most people today believe that other mammals, like dogs and cats, also have minds. Most scientists would agree that the limbic system has its own emotional consciousness.
What about the brainstem? Are fish, amphibians, and reptiles conscious? The traditional answer was no – the brainstem is not complex enough to generate consciousness. But this view has been changing, and many now believe that brainstem creatures do have some basic awareness. We can’t know what it’s like to be a fish or reptile, but it’s probably like something.
So where do you draw the line – insects, bacteria, inanimate matter? More and more scientists and nonscientists believe there is no dividing line. Consciousness has always been present, in all matter and energy, throughout the universe. The brain’s evolution just amplified and refined that which was already there. Terms like “latent mind” or “protoconsciousness” are sometimes used to suggest this glimmering life force, mostly hidden from us, but present through all of nature.
“Panpsychism holds that all matter has some mental attributes, and that there is a continuum from atoms through living organisms to the human mind…Not only animals, but plants, bacteria, and non-living matter share to some degree the essential properties [of mind].”
– Ethologist Donald Griffin
Panpsychism is difficult for many people to accept. It strains common sense and seems too mystical, suitable for primitive cultures but not ours. It’s often dismissed with jokes about talking to plants or what rocks think about. But is it really so far-fetched?
Certainly not if you believe in any kind of magic. Many conventional religious beliefs strain common sense as much or more than panpsychism. And panpsychism actually fits well with scientific worldviews –
It starts with “the central dogma of neuroscience” – brain energy fields are both physical and mental. It logically extends that principle throughout nature – all energy fields are both physical and mental.
So panpsychism also resonates with the findings of modern physics. As discussed in Essay 6, all energy fields are fundamentally interconnected and inseparable. Our minds are physical/mental energy fields, so must be part of that connectedness. Consciousness cannot be dissected out of the undissectable whole. It must be an integral part of the whole, an inherent aspect of all energy everywhere. Panpsychism defies common sense in the same way that modern physics does.
And like modern physics, panpsychism fits with the existence of magic –
According to panpsychism, paranormal events like telepathy and psychic premonitions must involve unknown physical/mental energy fields interacting with our brains’ physical/mental energies. The universe is an ocean of physical/mental energy fields, all fundamentally interconnected. They transcend space, time, and the laws of classical physics. Our understanding of them is limited, but paranormal experiences give us brief glimpses into hidden dimensions of nature and consciousness. According to panpsychism, the entire universe is physical and mental, mundane and mystical.
And as Einstein believed, there may be a unified field, a universal ground energy, the source of all other energy fields. Many scientists today believe this fundamental physical force does exist. If so, panpsychism asserts it must be both physical and mental. The unified field must also be universal mind. It must be the Holy Spirit (holy comes from the root word “whole”). It’s the unified field of science and spirit – the Creator – the source of all matter, mind, and magic.
So panpsychism seems to provide the best answer to the mind-body question. It seems to fit best with scientific and spiritual worldviews.
But again, we have no proof, and other answers are possible. Maybe the materialists and atheists are right after all, and consciousness is really an insignificant accident. Or maybe the opposite is true, as idealism claims, and the physical world is just an illusion. Or maybe dualism is closer to the truth, including dualist theologies that separate a Supreme Mind from a universe of mindless matter.
In fact, no one really knows. Perhaps we’ll know someday. But for now the question remains open, and debates continue, with no proof or disproof for any of those theories. For now the most important thing is humility in the face of the mystery, and respect for others’ opinions about it. Each person must find his or her own path and belief system, while respecting the paths and beliefs of others.
- Campbell, Anthony. Seven States of Consciousness. Harper and Row, New York, 1974.
- Edelman, Gerald. The Remembered Present. Basic Books, New York, 1989.
- Griffin, Donald. Animal Thinking. Howard University Press, Cambridge, 1984.
- Hippocrates. On the Sacred Disease.
- James, William. The Varieties of Religious Experience. Simon and Schuster, New York, 1977.