The Big Picture
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of which disagrees with the others about what should be eliminated and
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what should be kept.)
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What is real, and what is not, doesn’t seem like an intractable problem
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at first glance. The table in front of you is real; unicorns are not. But what
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if that table is made of atoms? Would it be fair to say that the atoms are real,
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but not the table?
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That would be a certain construal of the word “real,” limiting its appli-
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cability to only the most fundamental level of existence. It’s not the most
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convenient definition we can imagine. One problem is that we don’t, as yet,
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actually have a full theory of reality at its deepest level. If that were our
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standard for true existence, the only responsible attitude would be to say
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that nothing that human beings have ever contemplated is actually real. It’s
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a philosophy with a certain Zen purity, but it’s not very helpful if we would
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like to use the concept of “real” to distinguish certain phenomena from
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others. Wittgenstein would say that it doesn’t make sense to talk that way.
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A poetic naturalist has another way out: something is “real” if it plays an
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essential role in some particular story of reality that, as far as we can tell,
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provides an accurate description of the world within its domain of applica-
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bility. Atoms are real; tables are real; consciousness is undoubtedly real. (A
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similar view was put forward by Stephen Hawking and Leonard Mlodi-
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now, under the label “ model- dependent realism.”)
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Not everything is real, even by this permissive standard. Physicists used
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to believe in the “luminiferous aether,” an invisible substance that filled all
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of space, and which served as a medium through which electromagnetic
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waves of light traveled. Albert Einstein was the first to have the courage to
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stand up and remark that the aether served no empirical purpose; we could
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simply admit that it doesn’t exist, and all of the predictions of the theory of
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electromagnetism go through unscathed. There is no domain in which our
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best description of the world invokes the concept of luminiferous aether;
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it’s not real.
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Illusions are just mistakes, concepts that play no useful role in descriptions
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at any level of coarse- graining. When you are crawling across the desert
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sands, out of water and not completely in your right mind, and think you
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see a lush oasis with palm trees and a pond in the distance— that’s an illu-
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sion (probably), in the sense that it’s actually not there. But if you get lucky
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and it really is there, and you scoop up liquid water into your hand, that
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liquid is real, even if we have a more comprehensive way of talking that
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describes it in terms of molecules made of oxygen and hydrogen.
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Consciousness is not an illusion, even if we think it is “just” an emergent
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way of talking about our atoms each individually obeying the laws of
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physics. If hurricanes are real— and it makes sense to think that they are—
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even though they are just atoms in motion, there is no reason why we should
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treat consciousness any differently. To say that consciousness is real isn’t
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to say that it’s something over and above the physical world; it’s emergent,
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and it’s also real, just like almost every other thing we’ve encountered in
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our lives.
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Fundamental
Emergent/Effective Descriptions
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Underlying
Physics,
Morality,
Aether,
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Physical
Biology,
Aesthetics,
Phlogiston,
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Reality
Psychology
Meaning
Unicorns
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Real
Illusions
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Factual/
Constructed/
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Objective
Subjective
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How poetic naturalism divides up “fundamental” versus “emergent/ effective,” “real”
versus “illusion,” and “objective” versus “subjective.”
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Describing our naturalism as “poetic” is helpful because there are other
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kinds of naturalism out there. There are austere forms of naturalism that
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try to eliminate everything in sight, and insist that the only “true” way of
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talking about the world is the deepest, most fundamental one. On the
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other side of the spectrum are augmented forms of naturalism, which hold
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that there is more to the world at a fundamental level than mere physical
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reality. This is a grab- bag category that would include those who believe
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mental properties are real and distinct from physical ones, or those who
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believe that moral principles are as objective and fundamental as the physi-
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cal world.
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Poetic naturalism sits in between: there is only one, unified, physical
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world, but many useful ways of talking about it, each of which captures an
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element of reality. Poetic naturalism is at least consistent with its own stan-
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dards: it tries to provide the most useful way of talking about the world
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we have.
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The most seductive mistake we can be drawn into when dealing with mul-
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tiple stories of reality is to mix up vocabularies appropriate to different ways
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of talking. Someone might say, “You can’t truly want anything, you’re just
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a collection of atoms, and atoms don’t have wants.” It’s tr
ue that atoms don’t
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have wants; the idea of a “want” is not part of our best theory of atoms.
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There would be nothing wrong with saying “None of these atoms making
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up you want anything.”
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But it doesn’t follow that you can’t have wants. “You” are not part of our
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best theory of atoms either; you are an emergent phenomenon, meaning
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that you are an element in a higher- level ontology that describes the world
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at a macroscopic level. At the level of description where it is appropriate to
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talk about “you,” it’s also perfectly appropriate to talk about wants and feel-
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ings and desires. Those are all real phenomena in our best understanding of
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human beings. You can think of yourself as an individual human being, or
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you can think of yourself as a collection of atoms. Just not both at the same
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time, at least when it comes to asking how one kind of thing interacts with
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another one.
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That’s the ideal case, anyway. Following Galileo’s lead of ignor-
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ing complications and searching for simplicity, physicists have devel-
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oped formalisms in which the separation between different ways of
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talking—“effective field theories”— is precise and well-defined. Once we get
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beyond physics to the more nuanced and complex realms of biology and
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psychology, demarcating one theory from another becomes more difficult.
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We can talk about human beings coming down with an illness and becom-
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ing contagious, possibly passing on their disease to other people. “Illness”
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is a useful category in our vocabulary for describing human beings, with a
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reality all its own, independent of its microscopic underpinnings. But we
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know that there is a deeper level according to which that illness is a mani-
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festation of, for example, a viral infection. We can’t help but be sloppy and
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mix up our talk of people and illnesses and viruses into one big messy vo-
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cabulary.
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Just as investigating dualities between different physical theories
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provides full employment for physicists, investigating how different
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vocabularies relate to one another and sometimes intermingle provides
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full employment for philosophers. For our purposes, we can leave that as
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homework for the ontologically fastidious, and leap into a different ques-
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tion: How do we go about constructing a set of ways to talk about our
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actual world?
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Planets of Belief
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M
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ost people don’t lose sleep worrying whether the world they see
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is basically real, or whether they’re being tricked by an evil de-
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mon. We accept that what we see and hear reflects reality with
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at least some degree of reliability, and move on from there. This leaves us
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with a more subtle problem: how do we construct a comprehensive picture
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of how things work that is both reliable and consistent with our experience?
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Descartes was looking for a “foundation” for justified belief. A founda-
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tion keeps a structure firmly rooted in solid ground. Foundationalism is the
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search for such solid ground, on which to erect the edifice of knowledge.
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Science
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Evidence of Our Senses
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God, Omnipotent and Omnibenevolent
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Cogito Ergo Sum
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Knowledge as a series of beliefs resting on a secure foundation.
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Let’s take that metaphor more seriously than it perhaps deserves. On the
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scale of a human being, the ground beneath our feet is unquestionably solid
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and reliable. If we zoom out a bit, however, we see that the ground is simply
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part of the planet on which we live. And that planet, the Earth, isn’t
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grounded on anything at all; it is moving freely through space, orbiting
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around the sun. The individual bits of matter that constitute the Earth aren’t
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embedded in an unmoving structure; they are held together by their mutual
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gravitational force. All of the planets in the solar system formed gradually,
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as bits of rock and dust accreted together, each collection growing in influ-
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ence and pulling together what remaining scraps of matter it could.
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Without meaning to, we’ve discovered a much more accurate metaphor for
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how systems of belief actual y work. Planets don’t sit on foundations; they hold
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themselves together in a self- reinforcing pattern. The same is true for beliefs:
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they aren’t (try as we may) founded on unimpeachable principles that can’t be
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questioned. Rather, whole systems of belief fit together with one another, in
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more or less comfortable ways, pulled in by a mutual epistemological force.
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Many
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Big
Worlds
Bang
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Emergence
Abiogenesis
Poetic
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Quantum
Earth,
Naturalism
Logic
Fields
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Air,
Fire,
Practical
Bayesian
Death
Moral
Potency
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Water
Wisdom
Inference
Constructivism
and Act
Conservation
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Unmoved
of Information
Classical
Aether
Mover
Physicalism
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Unities
Empathy
Eudaimonia
Determinism
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Formal
Empiricism
Causes
Empiricism
Efficient
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Causes
Virtue
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Great
Chain of
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Being
Teleology
Catholic
Cogito
Church
Ergo
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Sum
God’s
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Perfection
Mind/Body
Dualism
Inertial
Motion
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Method
Analytic
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of Doubt
Geometry
Interaction via
Pineal Gland
Foundationalism
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The
Passions
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Rationalism
Causal
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Corpuscles
Adequacy
Vortices
Principle
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Knowledge as a set of beliefs held together by the “gravitational pull” of their mutual 35S
consistency. Parts of the planets of belief for Aristotle, Descartes, and a modern poetic 36N
naturalist.
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Pl A n E t S O F b E l I E F
In this picture, a planet of belief is much richer and more complex than
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simply an ontology. An ontology is a view about what really exists; a planet
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of belief contains all sorts of other convictions, including methods for un-
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derstanding the world, a priori truths, derived categories, preferences, aes-
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thetic and ethical judgments, and more. If you believe that two plus two
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equals four and chocolate ice cream is objectively better than vanilla, those
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are not parts of your ontology, but they are parts of your planet of belief.
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No analogy is perfect, but the planets-of-belief metaphor is a nice way to
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understand the view known in philosophical circles as coherentism. Accord-
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ing to this picture, a justified belief is one that belongs to a coherent set of
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propositions. This coherence plays the role of the gravitational pull that
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brings together dust and rocks to form real planets. A stable planet of belief