The Big Picture
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about why we have these particular laws of physics at all. Why quantum
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mechanics rather than classical mechanics? Why do we seem to have three
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dimensions of space and one of time, and the particular zoo of particles and
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forces we have discovered?
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It’s possible that some of these have partial answers within a larger
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physical context. Modern theories of gravity, for example, envision sce-
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narios in which the number of dimensions of spacetime can be different in
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different parts of the universe. Perhaps there is some dynamic mechanism
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that picks out 4 as a special number.
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But that can’t be the entire answer. Why would there be such a dynamic
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mechanism in the first place? Physicists sometimes fantasize about discov-
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ering that the laws of physics are somehow unique— that these are the only
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ones there possibly could have been. That’s probably an unrealistic
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pipe dream. It’s not hard to imagine all sorts of different possible ways the
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laws of physics could have been. Perhaps the universe could have been clas-
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sical, rather than quantum. Perhaps the universe could be a lattice, like a
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chessboard, with bits flipping from on to off as time passes in discrete units.
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Perhaps the sum total of reality could have been a single point, lacking ei-
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ther space or time. Perhaps there could be a universe that had no regulari-
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ties at all, one where there would be nothing we would recognize as a “law
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of physics.”
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There may be no ultimate answer to the “Why?” question. The universe
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simply is, in this particular way, and that’s a brute fact. Once we figure out
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how the universe behaves at its most comprehensive level, there will not be
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any deeper layers left to discover.
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Theists think they have a better answer: God exists, and the reason why
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the universe exists in this particular way is because that’s how God wanted
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it to be. Naturalists tend to find this unpersuasive: Why does God exist?
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But there is an answer to that, or at least an attempted one, which we al-
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luded to at the beginning of this chapter. The universe, according to this
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line of reasoning, is contingent; it didn’t have to exist, and it could have
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been otherwise, so its existence demands an explanation. But God is a nec-
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essary being; there is no optionality about his existence, so no further expla-28
nation is required.
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Except that God isn’t a necessary being, because there are no such things
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as necessary beings. All sorts of versions of reality are possible, some of
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which have entities one would reasonably identify with God, and some of
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which don’t. We can’t short- circuit the difficult task of figuring out what
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kind of universe we live in by relying on a priori principles.
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It’s important to be fair to both sides. Given a conventional understand-
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ing of what is meant by “God,” the fact that the universe exhibits
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regularities at all, and in particular that it exhibits regularities that allow
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for the existence of human beings, seems to have a higher likelihood under
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theism than under naturalism. A caring deity is more likely to produce hos-
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pitable conditions than a brute- fact cosmos. If the existence of a universe
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governed by physical laws were the only piece of information we had, that
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piece of evidence would tilt us in the direction of theism.
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It’s not the only piece of evidence we have, of course. As we saw in chap-
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ter 18, naturalists find many aspects of the universe that do not fit well at all
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with theism, and count heavily against it. The theistic side of the argument
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would be much stronger if it extended beyond “God would have wanted a
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hospitable universe to exist, and here we are” to specific aspects of the phys-
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ical world, especially ones we haven’t yet discovered. If you want to claim
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that the properties of our kind of universe provide evidence for God’s exis-
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tence, you need to believe that you understand God’s motivations well
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enough to say that it’s more likely God would have created this kind of
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universe rather than some other kind. And if that’s true, it’s natural to ask
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for even more. How many galaxies would God have wanted to create?
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What would God have made the dark matter consist of?
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There may be answers to these questions, either in naturalism or in the-
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ism. Or we may have to live with simply accepting the universe the way it
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is. What we can’t do is demand explanations that the universe may not be
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able give us.
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Body and Soul
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I
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n another world, just slightly different from ours, the woman we know
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as Princess Elisabeth of Bohemia might have been an influential and
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celebrated philosopher or scientist. Instead, her ideas come to us pri-
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marily from her correspondence with the great thinkers of her age, espe-
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cially René Descartes. Known as virtuous and pious, in her later years she
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served as an active leader of a major convent in Saxony. But she was most
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distinguished by her freedom of thought and questioning intellect, which
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led her to challenge one of Descartes’s most famous positions: m
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dualism, the idea that the mind or soul is an immaterial substance distinct
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from the body. If that were true, she insisted on knowing, how did the two
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substances communicate with each other?
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These days we would say it this way: our bodies are made of atoms,
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which are in turn made of particles, and those particles obey the equations
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of the Core Theory. If you want to say that the mind is a separate substance,
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not just a way of talking about the collective effect of all those particles,
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how does that substance interact with the particles? How are the equations
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of the Core Theory incorrect, and how should we improve them?
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•
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In the early seventeenth century, the Holy Roman Empire was a loose con-
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federation of city- states centered in modern- day Germany. One of the most
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influential of them was the Electoral Palatinate, a group of municipalities
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scattered along the Rhine. Elisabeth Simmern van Pallandt was born there
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Elisabeth of the Palatinate, Abbess of Herford Abbey and
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Princess of Bohemia, 1618– 1680.
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in 1618, daughter of Frederick V, Elector Palatine, and Elizabeth Stuart,
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who herself was the daughter of James I of England. Elisabeth’s upbringing
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seems tumultuous from our perspective, although perhaps it was a typical
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Central European royal childhood back in those days.
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Elisabeth didn’t grow up in Bohemia. After a short and unsuccessful
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stint as the ruling couple of Bohemia, her parents sought refuge in the
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Netherlands. Elisabeth was raised for a while by her grandmother in Hei-
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delberg, before moving to The Hague at the age of nine with other members
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of her exiled family. Through the upheaval she managed to obtain a wide-
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ranging education, including philosophy, astronomy, mathematics, juris-
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prudence, history, and classical languages, for which her fluency earned her
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the nickname “the Greek” among her brothers and sisters. Her father died
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when she was twelve, leaving her in the hands of an uninterested mother
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who would tease Elisabeth for her earnest, studious demeanor. Her life at
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home was probably not made any smoother by her penchant for valuing
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honesty over courtly manners.
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Despite not living an easy or luxurious life by princess standards, Elisa-
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beth managed to be active and engaged both intellectually and politically.
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She was committed to social justice, befriending and supporting William
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Penn and other influential Quakers, notwithstanding the theological dif-
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ferences they may have had with her own Calvinism. She received one re-
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corded offer of marriage, to the elderly King Wladyslaw IV of Poland,
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whom she had never met in person. The Polish Diet wouldn’t let the match
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go forward unless Elisabeth converted to Catholicism, which she refused
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to do, so the wedding was called off.
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In 1667 she entered the convent of Herford Abbey, where she eventually
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rose to the station of abbess. Elisabeth wasn’t the retiring sort of nun, but
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rather was an active philanthropist and humanitarian, offering the abbey
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as a place of refuge for anyone persecuted for reasons of conscience, as well
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as essentially governing the surrounding town. She died in 1680, having
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become gravely ill, but not before putting her affairs in order and writing a
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letter of farewell to her sister Louise.
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In our actual world, René Descartes certainly succeeded in becoming an
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influential and celebrated philosopher and scientist. As we have seen, he
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delved deep into skepticism of the physical world, ultimately relying on his
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belief in his own existence (and in God’s) to pull himself up by his boot-
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straps. But at the moment our concern is with Descartes’s mind- body
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dualism.
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It was in the Meditations on First Philosophy, the same work in which he
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established his own existence, that Descartes argued for the idea that the
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mind is independent of the body. It’s not a completely crazy thing to think.
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Both living organisms and nonliving objects clearly have “matter” in them,
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but conscious creatures are manifestly different in some important way
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from non- conscious lumps of stuff. The mind or the soul seems, at very first
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glance, to be something quite different from the body itself.
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Descartes’s argument was pretty simple. He’d already established that
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we can doubt the existence of many things, even the chair we are sitting on.
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So there’s no real problem doubting the existence of your own body. But
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you can’t doubt the existence of your mind— you think, therefore your
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mind must really exist. And if you can doubt the existence of your body but
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not your mind, they must be two different things.
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The body, Descartes went on to explain, works like a machine, having
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material properties and obeying the laws of motion. The mind is an entirely
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separate kind of entity. Not only is it not made of material stuff; it doesn’t
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even have a specific location on the material plane. Whatever the mind is,
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it’s something very different from tables and chairs, something that occu-
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br /> pies an utterly distinct realm of existence. We label this view substance dual-
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ism, since it claims that mind and body are two distinct kinds of substance,
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not merely two different aspects of one underlying kind of stuff.
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But the mind and body interact with each other, of course. Certainly
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our minds communicate with our bodies, nudging them to perform this or
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that action. Descartes felt that the interaction also went the other way: our
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bodies can influence our minds. This was a minority position at the time,
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although it also seems fairly unobjectionable at first glance. When we stub
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a toe, it’s the body that is first affected, but our minds certainly experience
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the pain. For a Cartesian dualist, minds and bodies coexist in an ongoing
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dance of influence and response.
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Elisabeth read Descartes’s Meditations in 1642, soon after they were first
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published. She was intrigued, but skeptical. Fortunately for her, (1) Des-
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cartes was himself living in the Netherlands at the time, and (2) she was a
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princess. Before too long she was able to bring up her worries with the phi-
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losopher himself.
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Elisabeth’s father had died in 1631, leaving her mother, Elizabeth Stuart,
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as the head of an indebted and unruly family. She would frequently host
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salons that entertained politicians, scientists, artists, and adventurers. Des-
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cartes attended one such event, at which Elisabeth was present, but the
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studious young woman didn’t muster the courage to engage the famous
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thinker in direct conversation. She did afterward speak of her interest in
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Descartes’s recent writings to a mutual friend, who passed word along
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to him.
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Having royal allies is always a good thing, even if the family is out of
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power and relatively poor. Accordingly, on his next visit to The Hague,
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Descartes once again stopped by the house of the exiled queen of Bohemia.
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Elisabeth, as fate would have it, wasn’t in at the time. A few days later, how-
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ever, he received a letter from her, the beginning of a correspondence that
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would last until his death in 1650.
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Elisabeth’s letters combine a mastery of formal etiquette with an intel-
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lectual’s impatient distaste for beating around the bush. After a few polite