The Big Picture
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thing “the same thing” as some other thing? But more broadly, they’re ques-
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tions about ontology, our basic view of what exists in the world. What
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kinds of things are there at all?
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When we ask about the identity of the “real” Captain Kirk or Ship of
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Theseus, a whole bundle of unstated assumptions come along for the ride.
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We are assuming that there are things called “persons,” and things called
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“ships,” and that these things have some persistence over time. And every-
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thing goes swimmingly, until we come up against a puzzle, such as these
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duplication scenarios, that puts a strain on how we define these kinds of
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objects.
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All this matters, not because we’re on the verge of building a working
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transporter, but because our attempts to make sense of the big picture in-
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evitably involve different kinds of overlapping ways of talking about the
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world. We have atoms, and we have biological cells, and we have human
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beings. Is the notion of “this particular human being” an important one to
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how we think about the world? Should categories like “persons” and “ships”
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be part of our fundamental ontology at all? We can’t decide whether an
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individual human life actually matters if we don’t know what we mean by
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“human being.”
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As knowledge generally, and science in particular, have progressed over the
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centuries, our corresponding ontologies have evolved from quite rich to
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relatively sparse. To the ancients, it was reasonable to believe that there were
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all kinds of fundamentally different things in the world; in modern
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thought, we try to do more with less.
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We would now say that Theseus’s ship is made of atoms, all of which are
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made of protons, neutrons, and electrons— exactly the same kinds of particles
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that make up every other ship, or for that matter make up you and me. There
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isn’t some primordial “shipness” of which Theseus’s is one particular exam-
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ple; there are simply arrangements of atoms, gradually changing over time.
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That doesn’t mean we can’t talk about ships just because we understand
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that they are collections of atoms. It would be horrendously inconvenient
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if, anytime someone asked us a question about something happening in the
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world, we limited our allowable responses to a listing of a huge set of atoms
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and how they were arranged. If you listed about one atom per second, it
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would take more than a trillion times the current age of the universe to
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describe a ship like Theseus’s. Not really practical.
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It just means that the notion of a ship is a derived category in our ontol-
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ogy, not a fundamental one. It is a useful way of talking about certain sub-
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sets of the basic stuff of the universe. We invent the concept of a ship
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because it is useful to us, not because it’s already there at the deepest level
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of reality. Is it the same ship after we’ve gradually replaced every plank? I
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don’t know. It’s up to us to decide. The very notion of “ship” is something
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we created for our own convenience.
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That’s okay. The deepest level of reality is very important; but all the
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different ways we have of talking about that level are important too.
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What we’re seeing is the difference between a rich ontology and a sparse
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one. A rich ontology comes with a large number of different fundamental
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categories, where by “fundamental” we mean “playing an essential role in
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our deepest, most comprehensive picture of reality.”
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In a sparse ontology, there are a small number of fundamental categories
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(maybe only one) describing the world. But there will be very many ways of
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talking about the world. The notion of a “way of talking” isn’t mere
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decoration— it’s an absolutely crucial part of how we apprehend reality.
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Love
Books
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Life
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Causes
Fire
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Prime
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Heaven
Numbers
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Duty
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Wetness
Earth
Humanity
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God
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Elephants
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Purpose
Marriage
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Flatworms
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Energy
Time
Society
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Happiness
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The
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Natural
Explanations
World
Color
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Laws
Virtue
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Atoms
Chairs
of
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Nature
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Cells
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Two different kinds of ontologies, rich and sparse. Boxes are
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fundamental concepts, while circles are derived or emergent
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concepts— ways of talking about the world.
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One benefit of a rich ontology is that it’s easy to say what is “real”— every
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category describes something real. In a sparse ontology, that’s not so clear.
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Should we count only the underlying stuff of the world as real, and all the
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different ways we have of dividing it up and talking about it as merely illu-
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sions? That’s the most hard-core attitude we could take to reality, sometimes
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called eliminativism, since its adherents like nothing better t
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around eliminating this or that concept from our list of what is real. For an
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eliminativist, the question “Which Captain Kirk is the real one?” gets an-
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swered by “Who cares? People are illusions. They’re just fictitious stories we
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tell about the one true real world.”
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I’m going to argue for a different view: our fundamental ontology, the
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best way we have of talking about the world at the deepest level, is extremely
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sparse. But many concepts that are part of non- fundamental ways we have
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of talking about the world— useful ideas describing higher- level, macro-
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scopic reality— deserve to be called “real.”
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The key word there is “useful.” There are certainly non- useful ways of
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talking about the world. In scientific contexts, we refer to such non- useful
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ways as “wrong” or “false.” A way of talking isn’t just a list of concepts; it
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will generally include a set of rules for using them, and relationships among
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them. Every scientific theory is a way of talking about the world, according
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to which we can say things like “There are things called planets, and some-
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thing called the sun, all of which move through something called space,
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and planets do something called orbiting the sun, and those orbits describe
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a particular shape in space called an ellipse.” That’s basically Johannes Kep-
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ler’s theory of planetary motion, developed after Copernicus argued for
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the sun being at the center of the solar system but before Isaac Newton
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explained it all in terms of the force of gravity. Today, we would say that
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Kepler’s theory is fairly useful in certain circumstances, but it’s not as useful
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as Newton’s, which in turn isn’t as broadly useful as Einstein’s general the-
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ory of relativity.
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The strategy I’m advocating here can be called poetic naturalism. The poet
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Muriel Rukeyser once wrote, “The universe is made of stories, not of at-
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oms.” The world is what exists and what happens, but we gain enormous
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insight by talking about it— telling its story— in different ways.
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Naturalism comes down to three things:
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1. There is only one world, the natural world.
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2. The world evolves according to unbroken patterns, the laws
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of nature.
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3. The only reliable way of learning about the world is by ob-
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serving it.
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Essentially, naturalism is the idea that the world revealed to us by scien-
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tific investigation is the one true world. The poetic aspect comes to the fore
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when we start talking about that world. It can also be summarized in three
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points:
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1. There are many ways of talking about the world.
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2. All good ways of talking must be consistent with one an-
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other and with the world.
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3. Our purposes in the moment determine the best way of
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talking.
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A poetic naturalist will agree that both Captain Kirk and the Ship of
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Theseus are simply ways of talking about certain collections of atoms
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stretching through space and time. The difference is that an eliminativist
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will say “and therefore they are just illusions,” while the poetic naturalist
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says “but they are no less real for all of that.”
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Philosopher Wilfrid Sellars coined the term manifest image to refer to
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the folk ontology suggested by our everyday experience, and scientific image
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for the new, unified view of the world established by science. The manifest
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image and the scientific image use different concepts and vocabularies, but
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ultimately they should fit together as compatible ways of talking about the
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world. Poetic naturalism accepts the usefulness of each way of talking in its
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appropriate circumstances, and works to show how they can be reconciled
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with one another.
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Within poetic naturalism we can distinguish among three different
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kinds of stories we can tell about the world. There is the deepest, most fun-
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damental description we can imagine— the whole universe, exactly de-
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scribed in every microscopic detail. Modern science doesn’t know what that
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description actually is right now, but we presume that there at least is such
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an underlying reality. Then there are “emergent” or “effective” descriptions,
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valid within some limited domain. That’s where we talk about ships and
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people, macroscopic collections of stuff that we group into individual enti-
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ties as part of this higher- level vocabulary. Finally, there are values: concepts
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of right and wrong, purpose and duty, or beauty and ugliness. Unlike
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higher- level scientific descriptions, these are not determined by the scien-
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tific goal of fitting the data. We have other goals: we want to be good peo-
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ple, get along with others, and find meaning in our lives. Figuring out the
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best way to talk about the world is an important part of working toward
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those goals.
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Poetic naturalism is a philosophy of freedom and responsibility. The raw
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materials of life are given to us by the natural world, and we must work to
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understand them and accept the consequences. The move from description
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to prescription, from saying what happens to passing judgment on what
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should happen, is a creative one, a fundamentally human act. The world is
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just the world, unfolding according to the patterns of nature, free of any
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judgmental attributes. The world exists; beauty and goodness are things
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that we bring to it.
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Poetic naturalism may seem like an appealing idea— or it may seem like an
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absurd bunch of hooey— but it certainly leaves us with a lot of questions.
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Most obviously, what is the unified natural world that underlies every-
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thing? We’ve been bandying about words like “atoms” and “particles,” but
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we know from discussions of quantum mechanics that the truth is a bit
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more slippery than that. And we certainly don’t claim to know the ultimate
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final Theory of Everything— so how much do we actually know? And what
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makes us think that it’s enough to justify the dreams of naturalism?
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There are equally many, if not more, questions about connecting that
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underlying physical world to our everyday reality. There are “Why?” ques-
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tions: Why this particular universe, with these particular laws of nature?
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Why does the universe exist at all? There are also “Are you sure?” questions:
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Are we sure that a unified physical reality could naturally give rise to life as
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we know it? Are we sure it is sufficient to describe consciousness, perhaps
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the most perplexing aspect of our manifest world? And then there are the
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“How?” questions: How do we decide what ways of talking are the best?
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How do we agree on judgmental questions about right and wrong? How do
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we find meaning and purpose in a world that is purely natural? Above all,
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how do we know any of this?
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Our task is to put together a rich, nuanced picture that reconciles all the
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different aspects of our experience. To put ourselves in the right frame of
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mind, in the next few chapters we’ll survey some of the ideas that helped
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set humanity on the road to naturalism.
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The World Moves by Itself
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