Cavendish’s philosophy stands in stark opposition to Descartes’s division between human being and animal. For Descartes, it is the mind that saves man from being all machine as “brutes” are.
In 1769, about eighty years after Cavendish was writing, another passionate materialist, Denis Diderot, was working on D’Alembert’s Dream, his sly, rambunctious work about the nature of life and the world, in which his dreaming thinker-hero says, “Every animal is more or less a human being, every mineral more or less a plant, every plant more or less an animal . . . There is nothing clearly defined in nature.”14 The Dream is dense with metaphors, perhaps most memorably the trope that the human organism has no greater claim to be seen as a single identity than a swarm of bees. Human beings are disparate collections of organs acting in concert. This, too, has a contemporary ring. There are any number of scientists and philosophers who dispute the idea that human beings have a fixed identity or self.
Diderot, a metaphorical wizard, was nevertheless suspicious of tropes. “But I shall abandon this figurative language,” he writes in Lettre sur les sourds et muets, “which I should only ever use to amuse a child so as to keep its attention from wandering, and shall return to the style of philosophy, which deals in reasons not comparisons.”15 Cavendish did not regard metaphor, emotion, or the imagination as pollutants of thought. She proposed a continuum of modes of understanding that included reason and “fancy,” or imagination. For Cavendish, the boundary between them was not rigid but elastic.
There are very few thinkers who begin at the beginning, who want to wipe away all received ideas in the manner of Descartes, but I found and still find that wish invigorating. Convictions about mind and matter as two things or one, the human body as a machine or as an organic, less predictable form survive in contemporary thinking in different disciplines. Descartes looked for certainty, which he found in the cave of his own isolated, thinking mind. A man sits alone in a room and thinks. This image remains central to the history of modern Western thought. How the man happened to find himself in that room is not often part of the picture. He must have been born, and he must have had a childhood, but the philosopher is a grown-up by definition. Even today, he is most often a he, not a she. There is no story or narrative, no temporal dimension to the lone cogitator seeking truth. A fully grown man sits in a room reflecting on the contents of another room—the mental space inside his own head.
Elisabeth, Princess of Bohemia, who initiated a correspondence with Descartes, pushed him to explain how an immaterial substance like the mind could possibly act on a material one—the body. She wrote, “But I nevertheless have never been able to conceive of such an immaterial thing as anything other than a negation of matter which cannot have any communication with it. I admit that it would be easier for me to concede matter and extension to the soul than to concede the capacity to move a body and to be moved by it to an immaterial thing.”16 She further noted, quite reasonably, that the condition of the body affects one’s capacity to think, that a person who has “had the faculty and the custom of reasoning well, can lose all of this by some vapors.”17 She also pressed him to take up the problem of emotion—the passions—in his model of mind and body, which he did.
Emotion has been a stubborn problem in both science and philosophy. Its role in human and animal life depends on your view of the mind. Unlike Hobbes and Cavendish, Princess Elisabeth was not inclined to reduce mind to body, but in her letters she is dubious that the human mind could be wholly independent of temporal and corporeal states. Although the language of her letters is colored by deference to the great man, and she refers to her weakness and inferiority, her critiques of her interlocutor’s ideas are bracingly astute. Few philosophers openly support dualism these days, but Descartes’s idea of a rational mind that can think its way into universal truths is alive and well in much of science and in the Anglo-American analytical tradition in philosophy, despite the fact that the very definition of mind is subject to heated, if not tortured, debates.
In direct opposition to Descartes’s thought and its broad influence, Giambattista Vico (1668–1744), scholar, historian, and professor at the University of Naples, mounted a vigorous defense of rhetoric, culture, and history through the power of metaphor and memory, which, he believed, were rooted in our bodily sensual experiences. In The New Science, Vico argued for a single “truth beyond all question: that the world of civil society has certainly been made by men, and that its principles are therefore to be found within the modifications of our own human mind.”18 While Descartes discovered truths that were static and universal, Vico’s truths included the uses of language and historical change.
For Vico, human consciousness itself had a story. To lift human reality out of its developmental narrative was absurd. Around the time I read Descartes for the first time, I also read Vico. I was probably twenty. I retained little from that first reading of the Neapolitan thinker—with one powerful exception: I remembered his giants. I imagined immense creatures, gray and wrinkled but upright, trudging heavily forward in a landscape of dun-colored earth. As evidence that these extinct creatures existed, Vico mentions the “Big Feet” reported in Patagonia and Homer’s Cyclops, beings of “a savage and monstrous nature.”19 Despite their rudimentary natures, Vico claims that even these galumphing folk had some “notion of God,” a notion that inaugurated their journey from impulsive, passionate, selfish creature to more thoughtful, civil human being.
Although Vico’s anthropology reminded me of some of the wilder tales told by the Greek historian Herodotus, the Italian’s big people serve as a way to understand the evolution of the human mind from prereflective to reflective. In one remarkable passage, he identifies his giganti as primitive persons who have not yet acquired the ability to recognize their reflections as their own. The ability to recognize one’s self in the mirror is regarded as a turning point in a child’s development. When the child identifies herself in the mirror, she is able to see herself as if from the outside, in the way another person would see her. She gains a form of self-consciousness she didn’t have before. Human beings master it at around eighteen months. But it is now known that other species are also capable of self-recognition—the great apes, elephants, some dolphins, and lots of birds. Vico writes, “For just as children try to grasp their own reflections when they look in the mirror, so primitive people thought they saw an ever-changing person in the water when they beheld how it altered their own features and movements.”20 For Vico, this ability to reflect about the self and the world has a narrative in human history, just as it does in the development of a single individual.
Educating children was among Vico’s chief concerns. He worried that if children were taught only reasoning skills and geometry in the mode of Descartes, they would become stunted beings with poor language skills. This debate is not over. In the United States, mathematics and science are generally viewed as more important than the humanities and the arts in education. Mathematics and science have an aura of seriousness, a disciplined severity the humanities and the arts lack. Hobbes’s elevation of reason to that which deals with addition and subtraction remains with us. Vico wanted to keep classical learning alive. He feared it would be lost to the Cartesian agenda. He also saw that increasing specialization in the universities was dividing knowledge into little pieces, in ways that made one field unintelligible to another.
The seventeenth century in Europe was beset with bloody religious wars and intellectual crises. It is hardly strange that the few granted the time, education, and means would look for certainty in a world where every verity appeared to be crumbling. Nobody is born a philosopher. Descartes’s name resides in a pantheon of “greats.” It is nevertheless good to remember that he was once a child, and a frail one. His mother died in childbirth a year after he was born. He firmly believed, however, he had been the cause of her death and that he inherited his weak health from her. Philosophers have stories, too. Descartes told one in a letter to Queen Christina of Swed
en. It was about a cross-eyed girl he had loved as a boy and how for years after, he “had felt more inclined to love” women “simply because they had that defect.” Once he understood this irrational association, however, it vanished.21 It will not surprise anyone that the inventor of analytic geometry excelled at mathematics in school.
The languages of our ideas are contagious. Words move from one person to another, and we are all vulnerable to coming down with a case of ideas, an infection that may last a lifetime. Human beings are the only animals who kill for ideas, so it is wise to take them seriously, wise to ask what they are and how they come about. All ideas are in one way or another received ideas. There are thinkers whom we consider to be original, but they too had to ingest the thoughts of others, usually in the form of books, to be able to think carefully at all. There is no thought without precedent. Despite his desire to cleanse his mind of all received knowledge, Descartes carried prior learning with him. Different times embrace different ideas, but some last longer than others, and there are ideas that become so entrenched that we are not even aware of them any longer. They lie beneath the controversies about what and who human beings are and remain unarticulated. They hide in metaphors and in phrases, in biases of one kind or another that we may fail to recognize and therefore rarely examine.
And then there is the further problem of various disciplines with wholly contradictory foundational beliefs, disciplines that have manufactured their own languages, in which the practitioners share assumptions about the world, so there is no need to question what everyone already believes. Vico’s critique of the academy and its isolated fields was prescient. Quarrels erupt regularly in academic circles, but often over what Freud called “the narcissism of minor difference.” The disputants do not battle over the first question but over the three hundred and forty-first question. Nearly all disciplines share a silent, often invisible consensus.
This is an essay that interrogates certainty and trumpets doubt and ambiguity, not because we are incapable of knowing things, but because we must examine our beliefs and ask where they come from. Doubt is fertile because it opens a thinker to foreign thoughts. Doubt is a question generator. Although Descartes’s first question about what is certain in our existence and what is not remains invigorating, his solution is less satisfying, not only to me, but to many others as well. One of the few universals when it comes to ideas may be that questions are normally better than answers. And yet, what does it mean for the human mind to investigate itself? This depends on what you believe a mind is. If the mind is a fallible, material thing, then the thoughts it generates will necessarily be limited, and they will change over time. If it is something else, however, if the human mind has access to truths out there in the universe, truths that are unchanging and lodged in the fabric of reality, you will have very different ideas about how to frame experience. Hannah Arendt was not alone in suggesting that for human beings to know what human beings are is a feat rather like “jumping over our own shadows.”22 Nevertheless, we persevere. The question is far too interesting to be left alone.
A Random Unscientific Survey of What People Think About the Mind (A Parenthetical Remark About Why I Am Writing This Book), and a Small Detour into the Mind of Alfred North Whitehead
While I was preparing to write this essay, I asked a number of people the same question: What do you think the mind is? I asked people I had never met before, and I asked people I already knew. I always told my interlocutors that the question was open. I wasn’t looking for the “right” answer. I was genuinely curious about what she or he had to say. The people I spoke to were all educated Americans or Europeans, but none of them had spent years forming theories about mental activity. Most of them weren’t sure how to define the mind. In fact, several were dumbfounded by the question. Although we all have “things on our minds” and sometimes “speak our minds” or try to be “mindful” of this or that, the mind is an elusive concept. To be helpful, I would ask a follow-up question: Do you think the mind is different from the body? Nearly every person made the conventional distinction between the mental and the physical. The mind thinks. The body does not. Descartes believed in just this kind of dualism: the thinking mind and the sensing body are made of different substances, but they interact. I would then ask if the brain and the mind are the same thing or if they are different. The answers to this question varied considerably. Some thought the brain and the mind are identical; others did not. It is easy to see how quickly simple questions about the mind become bewildering problems about essences.
If a person believes the mind is something different from the brain, then the question is, what is the mind made of that the brain is not? Is there something beyond our gray matter that must be considered in order to conceive of the mind? Is the mind immaterial? One man seated next to me at a dinner who firmly believed the mental and the physical were different became quite exercised when I asked him what the mental was made of. Was it God or spirit or mathematical truth? He was vehemently opposed to any mention of divinity, and our conversation pretty much ended there. He knew mind and body were two things but did not want to talk about what they might be.
On the other hand, if the mind is the brain, and the brain is just another organ of the body, an organ like the heart or the liver or the transient placenta, why is the mind considered to be something more elevated than a body part? This thought also made some people uncomfortable. Many of us locate the essence of ourselves inside our heads, inside our thinking minds. If my mind goes, so do I. If I lose my leg, however, I am still here. My leg is not myself in the way my thoughts are, despite the fact that they both belong to me. It is fair to ask, why should anyone care about what the mind is? It is obvious that many people go through life without losing one minute of sleep over it. It matters, I think, because how one resolves the problem has consequences in many disciplines, even when it is more or less hidden from view. For example, if mental problems are brain problems and not mind problems, why do we have psychiatry to treat the mind and neurology to treat the brain? Why not just one discipline to treat the brain? Every day we get news from the frontiers of brain science, genetics, and artificial intelligence, and the content of those reports is determined by how particular scientists understand the mind-body problem.
It has become obvious to me that framing the mind is crucial to many kinds of research. A single example will suffice. Depression is a poorly understood illness. No one knows how ordinary sadness and depression are related. A popular and effective treatment for depression has been cognitive behavioral therapy, or CBT. In many articles, papers, and advertisements, advocates for CBT articulate some version of the following: “negative dysfunctional thinking affects a person’s mood, sense of self, behavior and even physical state.”23 CBT assumes that by changing a person’s negative conscious thoughts to more positive ones, he can think himself better. The therapy isolates “thoughts”—what a patient is aware of thinking—from his physical state. Thoughts act on the body. Therefore thoughts in CBT are understood to be distinct from the body and able to manipulate it in mysterious ways. This is a philosophical problem because the thoughts appear to be immaterial, made of nothing.
Epiphenomenalism is the doctrine that conscious experience does not exert causal effects on the body. Although most of us feel pretty sure our thoughts do affect our behavior, how that might work remains a conundrum. Echoing Princess Elisabeth, the American analytical philosopher John Searle articulates the dilemma: “But if our thoughts and feelings are truly mental, how can they affect anything physical? How could something mental make a physical difference? Are we supposed to think that our thoughts and feelings can somehow produce chemical effects on our brains and the rest of our nervous system?”24 How one answers questions about depression and its treatment depends on a theoretical model of the mind. CBT assumes a Cartesian dualist divide, but its advocates choose not to worry about this riddle. There have been many studies that show CBT is effective for depression. Of course, j
ust because a treatment works does not mean it works for the reasons its champions claim it does.
The mind-body problem quickly becomes the person-environment problem. How does what is outside a person’s mind-body become the inside of that same mind-body? Where do words begin? Do they start outside the body in a shared language or inside the body in a native ability to learn to speak? Mice don’t talk the way we do. If a personality or character is mostly genetically predetermined, then the conditions of the outside world may look less important than tinkering with the genome. Maybe a tendency to depression is inborn. If the mind is the brain and nothing more than the brain, and if that brain works like a machine that has different parts for different functions, and it can be taken apart and put back together again, this idea will also affect how we think about a depressed person.
If the mind is a Hobbesian machine, then we might be able to build one that will never be depressed, and someday soon perpetually happy androids will hobnob with people. If like Descartes, and Pythagoras before him, you believe that the mind is not material, that truth is number, and unchanging mathematical truths rule the universe, then your view of the brain-mind and body will be determined by those truths and not by worries about the organic realities of flesh and bone. If you worry about depression at all, you will think about it in terms that go beyond the body. If, on the other hand, you believe the mind-brain is more fluid and dynamic, that animals have minds, too, that the mind-brain is more Vico-like than Hobbesian, that it changes in relation to experience, then you will have to look at the depressed person’s relations with other people in his life to find at least some of the answers for what went wrong.