I have been working on the idea that social neuroscience might support Lockean liberalism--particularly, the Lockean principles of self-ownership and natural punishment. As part of that work, I have been studying Thomas Willis to see how much influence he might have had on Locke. Willis is sometimes said to have been "the first neuroscientist" because of his anatomical and functional studies of the brain and nervous system. He was one of Locke's teachers at Oxford University and one of Locke's colleagues in the Royal Society.
While thinking about the questions raised by Willis's brain science, I started to review my notes from a Liberty Fund conference that I organized in 2004 in Tucson, Arizona on "Liberty in the Evolution of the Human Brain." I decided to post those notes here.
Can a scientific
understanding of the evolution of the human brain explain the natural basis of
human liberty? Or does a purely
naturalistic science of the brain subvert liberty by denying free will? Can our common-sense experience of exercising
free choice be compatible with Darwinian evolution and neuroscience? Or does a purely naturalistic science of
evolution and the brain disparage our experience of free will as an
illusion? Does free will require some
notion of an immaterial soul that is not reducible to material mechanisms? Can human morality be explained as rooted in
human biological nature? Or does the
human sense of moral obligation—the perception of a moral “ought”—transcend our
biological nature? How do these
questions about our metaphysical and moral freedom influence our understanding
of political freedom?
These are some of
the questions that were raised in this Liberty Fund colloquium. Although we surely did not answer any of
these questions conclusively, we came away with a better understanding of the
questions and of the possible answers.
were diverse in their backgrounds, which included law, biology, economics,
philosophy, psychology, political science, journalism, and literature.
The readings were
selected from three books: Oliver Sacks,
The Man Who Mistook His Wife for a Hat,
and Other Clinical Tales (1985), Karl Popper and John Eccles, The Self and Its Brain (1983), and
Daniel Dennett, Freedom Evolves
I will note a few of
the high points of the discussions.
SESSION 1: THE NEUROLOGY OF THE SOUL
Sacks, pages 1-5,
stories about the weird and poignant consequences of brain disorders were
welcomed by the participants as
engaging, although often troubling, stories.
Most of the
participants spoke about how disturbing these stories were, because the stories
depicted how fragile our human identity could be and how easily we could lose
our identity through brain damage. Some
of the participants spoke of their own experiences of physical suffering and
their feelings of losing control.
And yet, some
participants spoke of how Sacks’ stories were uplifting because of the kindness
and artistry of Sacks himself.
Sacks’ stories led
us into a discussion of how the mind arises from the brain. The participant who is a philosopher briefly
surveyed the various positions among contemporary philosophers as to the
Some of the
participants commented on the importance of dramatic narrative for Sacks as
depicting “the human subject, striving to preserve its identity in adverse
circumstances.” This suggests that the
soul itself arises more from dramatic narrative than it does from the brain as
a computational machine. Sacks seems to
be attacking the notion of the mind as a mere machine.
And yet some
participants suggested that we could in principle build machines that could
tell a story, machines with intentions or purposes. If so, then a mechanistic view of mind might
In the story of Ray,
who suffered from Tourette’s Syndrome, Ray spoke of how normal people have a
“natural freedom” that comes from a “natural balance” in their souls, while he
had to create an “artificial balance” through using the drug Haldol, so that he could balance the manic exuberance
of his Tourette’s against the sober calmness induced by the Haldol.
wondered whether the “coherence” of the soul was the crucial thing—maintaining
its continuity through time.
commented on the importance of Sacks in guiding us through these stories. One participant compared him to Dante guiding
his readers through Purgatory.
It was observed by
some that Sacks’ patients are not free because they have to deliberately
control things that in normal people are handled automatically without
conscious control. For example, the “disembodied
lady,” who had lost the proprioceptive sense of her own body, had to
consciously control her body movements through carefully watching her body in
It seemed that we
cannot be truly free when our bodies and minds are in so much conflict that we
must deliberately strain to control them, striving to achieve an “artificial
balance” where normally we would have a “natural balance.”
At the end of this
discussion session, we were left with various questions. Do clinical stories about the sometimes weird
consequences of brain disorders teach us anything about the relation between
the human mind and the activity of the brain?
Do they show that a person’s mental activity and personal identity are
reducible to the material mechanisms of the brain? Or do such stories sometimes suggest the
freedom of the human spirit to preserve its freedom and nobility even when the
brain is disabled?
SESSION 2: REDUCTIONIST MATERIALISM AND EMERGENT
Popper and Eccles,
pages 3-17, 33-60, 72-81, 98-99
These readings come
from Karl Popper, who argues against the materialist position that the physical
world is closed upon itself, so that the only effective causes in the universe
are purely physical causes. Rather, Popper
claims, we need to recognize three “Worlds”—“World 1” (the physical world),
“World 2” (the self-conscious mind), and “World 3” (the products of the human
mind, such as language, art, and science)—as interacting causally with one
asked, Is it true—as Popper says—that the openness of World 1 is needed to
explain human freedom? Someone answered
that this is not needed, as long as one sees that World 1 is in fact many
worlds at different evolutionary scales—from non-living entities to living
organisms to self-conscious animals.
Generally, most of the participants were skeptical of Popper’s dualism.
suggested that both Popper and Dennett were “emergentists,” although Dennett
was defending a “weak” form of emergence, while Popper was defending a “strong”
form of emergence. In Dennett’s thought,
complex forms emerge from less complex forms naturally. In Popper’s thought, these more complex,
emergent realities—particularly, self-conscious thought—become detached from
the physical world and exert a “downward causation” on that physical world.
observed that whatever plausibility Popper and Eccles had, it came from their
appeal to the common-sense, introspective experience of most people that they
exercise a freedom as self-conscious minds to control their brains and
bodies. Some participants questioned
whether we had to take such introspective experience as decisive. Isn’t introspection fallible? But even if it is fallible, one person
responded, it is a “data point” that needs to be taken seriously. And someone insisted that it is hard to just
deny this common experience of freedom.
There was some
discussion of whether modern science tended to promote determinism, or
whether—on the contrary—modern science tended to undermine determinism with
quantum mechanics and chaos theory. But
then some participants suggested that saying something was unpredictable was
not the same as saying it was uncaused or undetermined.
In defense of
Popper’s idea of World 3, one participate asked, What’s wrong with Popper’s
claim that “standards of logic are not physical properties”? Some people responded by saying that if our
physical universe were different, our logic might be different, so that in some
manner, logic might be rooted in physical reality. Or one might say that the laws of logic are
preconditions for any universe at all.
SESSION 3: THE DUALISM OF MIND AND BRAIN
Popper and Eccles,
pages 225-235, 250-51, 272-94, 311-13, 355-76, 437-57, 554-61
The readings for
this session come from John Eccles, a Nobel-prize-winning neuroscientist who
defends a strong form of dualism, even to the point of suggesting that the
self-conscious mind could be immortal.
The question here is whether the self-conscious mind transcends the
brain in ways that manifest the spiritual freedom of a soul that is
supernaturally created to be immaterial and immortal.
Another question is
whether Eccles’ survey of human neurological science supports his dualism. The discussion began with a philosopher who
has studied neuroscience offering a survey of recent developments in
neuroscience. He suggested that these
recent advancements provided detailed explanations for how the mind arises as
the activity of the brain, and thus this weakens Eccles’ argument for dualism.
agreed that it was not clear that the purely scientific evidence supported
Eccles’ position. Some suggested that
Eccles was motivated by a fear of death and a yearning for immortality of the
soul, which pushed him towards finding scientific confirmation for his
yearning. In any case, it would seem
from the evidence provided by Eccles himself that any immortality of the soul
would require immortality of the body to sustain the soul, which would require the
religious idea of resurrection of the body.
There was a
sustained discussion of consciousness—whether it is uniquely human, or whether
other animals are conscious as well.
Some people wondered
whether we needed full self-consciousness for moral responsibility. Don’t we have levels of responsibility, so
that nonhuman animals and young children can act voluntarily, although they
might not show self-conscious deliberate choice such as we might expect from a
mature human adult?
thought that the question of the soul is universally of concern to human
beings. We must explain this—this
yearning for some purpose larger than oneself.
Popper stresses that
there is no “ultimate explanation” for anything, because every explanation
ultimately depends on unexplained starting points. So if we ultimately appeal to the laws of
nature, we assume that uncaused nature is the starting point for explanation
that cannot itself be explained. But if
we look beyond nature to God as nature’s Creator, then we assume that uncaused
God is the starting point. We cannot
conclusively decide this disagreement.
But this could be used by religious believers to argue for the
limitations of scientific explanation.
SESSION 4: NATURAL
FREEDOM, CULTURAL FREEDOM, AND MORAL FREEDOM
Dennett, pages 1-22,
Dennett argues that
a naturalistic explanation of the evolution of the human brain can support the
freedom of human beings as cultural and moral animals. Determinism, he claims, does not mean
inevitability. Animals can evolve to
avoid dangers in their environment, and this flexible behavior has been highly
developed in human beings.
suggested that Dennett’s rhetorical style displays arrogance towards the
readers he wants to persuade, and thus he is unlikely to persuade. He uses the Walt Disney story of Dumbo the
elephant to suggest that believers in an immaterial soul need to believe in
“magical feathers” that allow them to fly.
responded that Dennett—and those like him—might have persuaded some undecided
students who were unsure of whether modern science could be compatible with
And yet some thought
that sometimes Darwinists are “true believers” who assume metaphysical
naturalism without proving it.
thought that the mystery of the origin of the universe and the origin of life
left plenty of room for a sense of wonder and awe that might be religious.
There was some
discussion of whether Dennett was employing a “sleight of hand” in the way he
defined “free will” as “evitability.” A
butterfly on a train track can fly away to avoid a train. But, according to Dennett, the butterfly is
determined to fly away.
Dennett makes much
of cultural evolution—as “mimetic” evolution.
But then, one participant observed, mimetic determinism is still determinism.
There was a
discussion of whether morality could be explained as rooted in moral emotions
as “commitment devices,” as suggested by Robert Frank.
SESSION 5: HOW THE BRAIN MAKES UP ITS MIND
For this session,
the question was, If mind is what the brain does, and if the brain is a purely
material mechanism with no place for an immaterial soul, does that mean that
our brains make decisions without our having any free will? Or can our free decisions show a form of free
will that arises from the natural mechanism of the brain?
insisted that a deterministic system can enable free choice, just as the
artistic rules for some genre of art can generate artistic freedom.
argued that cognitive science can list the features that make a system more in
control and then compare systems as more or less in control, more or less
free. For example, having a model of the
world, having a language, having more than two options, having memory—these and
other features would make a system freer than one without such features.
suggested that in working out the levels of freedom, we need a nested hierarchy
of three kinds of order (such as one finds in Aristotle, Darwin, Hayek, and
others)—nature, custom (or habit), and reason.
So, first, we need nature as genetic evolution. Then, we need custom or habit as cultural
evolution, which is constrained by genetic evolution. Finally, as mature human beings we have the
capacity for rational choice, which is constrained both by genetic evolution
and cultural evolution. The first two
levels—nature and custom—are spontaneous orders. The third—rational choice—is a deliberate order. Consider, for example, marriage law. As human beings, we have natural inclinations
to sexual mating and parental care.
These natural inclinations are expressed in cultural traditions as to
the norms of marriage and familial bonding.
Finally, we might decide by deliberate choice to favor some forms of
marriage over another; but this deliberate choice would be constrained by both
nature and custom. The current debate
over whether the law in the United States should sanction homosexual marriage
illustrates this. Similarly, the laws
governing incest avoidance illustrate this nested hierarchy.
But then one
participant suggested that biotechnology will give us the power to reshape
human nature, and perhaps even abolish it.
Others responded that the power of biotech will be constrained by
natural human desires and propensities.
For example, when a 63 year old woman had a child using reproductive
biotech, many people thought this would radically change the nature of human
reproduction. But, in fact, most 63 year
old women will not want to become pregnant.
This and other kinds of biotech innovations will not change the human
condition when they go against the natural propensities of most people.
There was some
discussion of how in vitro fertilization has weakened our repugnance towards
“unnatural” reproductive technology.
This is a result of our seeing that this has succeeded in allowing
people to have healthy children who have no other means of procreation. And yet if medical studies were to show that
IVF children were subject to serious genetic defects, that might arouse our
repugnance. Here reason and emotion are
combined in our moral judgments.
SESSION 6: THE FUTURE OF HUMAN FREEDOM
leader asked the director of the colloquium to open this session with a series
of questions. He offered three sets of
questions. First, since we began by
speaking about how disturbing Sacks’s stories were—because they arouse our fear
of annihilation or of losing our identities—we might ask whether science can explain
that fear and help us face up to it. Or
does such a fear show religious longings that science can never satisfy?
most of us seem to reject the Popper/Eccles position of dualism, we should ask
ourselves whether we have a good alternative.
If we look to Dennett for an alternative, it’s not clear how coherent
his alternative is. After all, doesn’t
his cultural evolution look at lot like Popper’s World 3? Has Dennett replaced the immaterial soul with
an immaterial culture? Many evolutionary
psychologists reject the naturalism of Darwin and, instead, adopt the dualism
of T. H. Huxley, who argured that morality requires culture as “an artificial
world within the cosmos.”
The third set of
questions concern the legal and political implications of Darwinian
naturalism. Dennett says that “the real
threats to freedom are not metaphysical but political and social,” and that we
need to agree on governmental and legal systems that are compatible with a
scientific understanding of human nature.
What would these governmental and legal systems look like? Paul Rubin (in Darwinian Politics) and Steve Pinker (in The Blank Slate) argue that a Darwinian science of human nature
supports a Tragic Vision of human nature—as opposed to a Utopian Vision. (The distinction between the Tragic Vision
and the Utopian Vision comes from Hayek as elaborated by Thomas Sowell.) And this Tragic Vision supports the
principles of modern democratic republicanism—limited government, individual
liberty, the rule of law, and free markets.
But is this true?
responded to these three sets of questions.
I will summarize a few of the responses.
To the first set
of questions: Yes, religion
can work to reassure us. Science gives
us little reassurance in facing up to the fear of annihilation. But science can look for cures for our mental
maladies. The fear provoked by Sacks’
stories is not fear of death but fear of continued physical existence with loss
of soul or deformity of mind. If death
is total oblivion, it need not be fearful (as Lucretius argued). Someday death might be optional as biotech
and biomedical medicine extend life.
Religion might actually promote fear of death by creating fear of
punishment after death.
To the second set
of questions: Yes, Huxley
broke from Darwin, but later Darwinians (like Dewey) defended Darwin’s position
by arguing that moral culture cultivates the natural potentialities of human
nature. We don’t need to accept a
radical dualism of facts and values because there are natural ethical facts
about what is required for proper human flourishing given our nature. Substance dualism is wrong. But matter-form dualism is defensible in
Dennett. After all, the power of
“information” (such as the DNA code) shows how “form” rules over “matter” in
the natural world, without requiring a radical substance dualism. We can explain morality as a purely natural
product without any dualistic transcendence of nature, because morality arises
as cooperative concern for others as an end in itself (proximate motivation), although
the ultimate explanation is that this was favored by evolution by natural
selection promoting reproductive success.
Evolution creates beings with purposes, even though the evolutionary
process itself is not purposeful. At
least one participant argued that Darwinian evolution was necessary but not
sufficient to explain morality, because human beings have the potentiality to
develop moral norms of right and wrong that surpass biological instincts.
To the third set
of questions: Darwin can explain the natural desire for
freedom as rooted in the instinct of the human animal to protect oneself
against harm and exploitation. Darwin
confirms that human beings are self-governing creatures. We have a Darwinian function to be free. The criminal code manifests a Darwinian
notion of the normality of responsibility versus the abnormality of people who
are not responsible for their behavior.
Political freedom is rare in history, and so this looks like a novelty
created by cultural evolution in the last few hundred years. Has this changed human nature? Historically, Darwinism was interpreted as
supporting socialism (Alfred Russel Wallace), fascism (Ernst Haeckel),
feminism, and many other ideologies.
This suggests that Darwinism has no clear political content. Like other forms of social thought, Darwinism
can be abused by various ideologies. But
surely Darwinism denies the Leftist assumption of human perfectibility (as
conceded by Peter Singer).
Over the years, I have written a series of posts on the emergent evolution of the soul in the brain that that is close to the position taken by Popper (here, here, here, and here). I have also written about Oliver Sacks (here).