The Big Picture
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new behaviors, are not incorporated into our genetic information, and are
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therefore not passed down to subsequent generations. (There are nuances
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here, as some environmentally influenced ways that genes are expressed may
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be heritable, even if the genes themselves don’t change.) Option 2 is a more
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standard Darwinian explanation. It’s not that previous generations of
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giraffes wanted to reach higher; it’s just that those that did accrued an ad-
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vantage that was passed on to their descendants.
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Then there is option 3, known as “sexual selection.” It is a perfectly plau-
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sible Darwinian explanation, one that relies on a specific mechanism of
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selection pressure to achieve the empirical result. Some researchers have
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suggested that a form of sexual selection is a better explanation than the
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traditional leafy- treetop story that we tell about the length of giraffe necks.
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This illustrates one of the difficulties in understanding how evolution actu-
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ally proceeds in the real world: there may be more than one way to explain
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the emergence of a single trait.
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The debate is ongoing. For example, under sexual selection it’s likely that
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male and female giraffe necks would evolve differently, but the data seem to
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indicate that they are fairly similar. Option 2 is currently more popular, but
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new data will continue to impact our credences for each of the different
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hypotheses.
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So what about option 4, which avoids any particular evolutionary story-
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telling? It’s a true statement, but not a useful one in this context. From the
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poetic- naturalism perspective, natural selection provides a successful way
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of talking about emergent properties of the biological world. We don’t need
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to use a vocabulary of evolution and adaptation to correctly describe what
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happens, but doing so gives us important and useful knowledge.
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The evolution of life provides a rich source of higher- level phenomena
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emerging from the fundamental description of reality, including phenom-
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ena that have no direct analogue at the deepest level. Because our specific
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universe starts in a special state and shows a strong arrow of time, these
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emergent pictures can invoke words like “purpose” and “adaptation,” even
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though those ideas are nowhere to be found in the underlying mechanistic
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behavior of reality.
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A common concern among skeptics of evolution is how it is supposed to
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lead to the creation of new kinds of things out of the mindless motion of
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matter. “Purposes” are one obvious example. We say, without apparent em-
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barrassment, things like “The purpose of the giraffe’s long neck is to help it
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reach fresh leaves near the treetops.” Another example is “information.”
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DNA is said to carry genetic information; the optic nerve carries informa-
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tion from the eye to the brain. Then there is consciousness itself. The con-
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cern is that these concepts represent a radical break from the mere Laplacian
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working- out of the laws of physics. How could evolution, which itself is
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ultimately purely physical, bring these utterly new kinds of things into ex-
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istence?
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It’s a natural thing to worry about. The process of evolution is unplanned
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and unguided. Whether or not genetic information gets passed on to future
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generations depends only on the conditions of its immediate environment
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and random chance, not on any future goals. How can an intrinsically pur-
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poseless process lead to the existence of purposes?
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But this worry is a little strange, at least in the hands of anyone who ac-
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cepts that natural selection provides an explanation for more prosaic things
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like gills and eyeballs. These kinds of organs are “utterly new” in their own
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way. There is no general principle along the lines of “new kinds of things
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cannot naturally arise in the course of undirected evolution.” Things like
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“stars” and “galaxies” come to be in a universe where they formerly didn’t
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exist. Why not purposes and information?
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In poetic naturalism, the appearance of “truly new” concepts as one
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theory emerges from another is the least surprising thing in the world. As
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time passes and entropy increases, the configuration of matter in the uni-
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verse takes on different forms, enabling the emergence of different higher-
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level ways of talking. The appearance of something like “purpose” simply
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comes down to the question “Is ‘purpose’ a useful concept when developing
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an effective theory of this part of reality in this particular domain of
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applicability?” There may be any number of interesting and challenging
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technical issues to be addressed, but there is no obstacle to the emergence
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of all kinds of new concepts along the way.
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Think about Robby the Robot, cleaning up cans from his grid. In the most
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successful strategies that were artificially generated through many genera-
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tions of variation and selection, Robby had evolved a technique of not pick-
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ing up a can on his current square if there were also cans to the east and
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west. Rather, he would move in one direction— let’s say west— until he ar-
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rived on a square with a can, but no can on the square just west of his loca-
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tion. Only then would he double back, picking up all the cans along the way.
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Why does Robby act in this way? We could simply say, “Those moves are
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part of the strategy that survives the genetic algorithm process.” That would
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be the equivalent of answer 4 in the list of giraffe- neck expl
anations above.
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It’s not wrong, but it’s not very illuminating either. Or we could say, “Robby
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doesn’t want to forget that there are cans on either side, so he leaves them
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in place, knowing he will come back and pick them up later.”
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Is that a sensible way of talking? Robby the Robot doesn’t really want
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anything. He’s not even a real robot— just a string of ones and zeroes inside
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some computer memory. Psychologists sometimes speak of the “anthropo-
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morphic fallacy,” when we attribute human thoughts or emotions to in-
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animate objects. (My computer gets grumpy if I don’t reboot it every so
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often.) It may be fun and harmless to speak about Robby as if he has wants,
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but it’s not really true. Right?
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Consider the possibility that we have this backward. When we say that
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Robby the Robot doesn’t really have wants in the same sense that a person
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does, we are taking the implicit stance that there are things called “wants”
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that can be correctly attributed to some things in the universe (like human
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beings) and not to others (like virtual robots). What are these “wants”
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anyway?
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The idea that something wants something else is a way of talking that is
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potentially useful in the right circumstances— a simple idea that summa-
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rizes a good amount of complex behavior in a convenient way. If we see a
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monkey climbing a tree, we could describe what’s happening by providing
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a list of what the monkey is doing at each moment in time, or for that
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matter we could specify the position and velocity of every atom in the mon-
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key and the environment at each moment. But it’s immensely easier and
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more efficient to say, “The monkey wants those bananas that are up in the
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tree.” The fact that we can say that is a piece of useful knowledge over and
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above all of those positions and velocities.
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There is no Platonic idea of a “want” floating out there in the space of
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ideas that can be properly associated with some kinds of beings and not
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with others. Rather, there are situations in which it is useful to describe
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things as somebody wanting something, and other situations in which that
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is not so useful. These situations can emerge in the natural, undirected evo-
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lution of matter in the universe. Those wants are as real as things ever get.
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In the particular case of Robby, it is neither necessary nor especially
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helpful to characterize his behavior in terms of wants, purposes, or desires.
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It’s just as easy to simply say what his can- collecting strategy actually is. But
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the difference between him and a person, as far as the ontological status of
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“wants” is concerned, is simply a matter of degree. We could imagine a ro-
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bot with an enormously more complicated programming than little Robby.
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We might not know much about that specific programming, but perhaps
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we are able to observe how the robot acts. It may be that the best way of
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understanding the robot’s behavior is to say, “That robot really wants to
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pick up those cans.”
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Under naturalism, there isn’t that much difference between a human
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being and a robot. We are all just complicated collections of matter moving
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in patterns, obeying impersonal laws of physics in an environment with an
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arrow of time. Wants and purposes and desires are the kinds of things that
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naturally develop along the way.
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There is a similar story to tell about “information.” It’s worth thinking
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about, as it will come up again when we start talking about consciousness.
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If the universe is just a bunch of stuff obeying mechanistic physical rules,
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how can one thing ever “carry information” about anything else? How can
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one configuration of atoms be “about” some other configuration?
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Words like “information” are a useful way of talking about certain
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things that happen in the universe. We don’t ever need to talk about
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information— we can take the “option 4” viewpoint and just talk about the
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quantum state of the universe inexorably evolving through time. But the
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fact that information is an effective way of characterizing certain physical
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realities is a true and nontrivial insight onto the world.
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Consider the Voynich manuscript. This is a remarkable and unique
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book, whose likely provenance has been traced to the early fifteenth cen-
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tury, possibly from Italy. It is a whimsical volume, replete with fanciful il-
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lustrations of astronomical and biological subjects. For the most part, the
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many flora depicted in the illustrations cannot be identified with actual
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plant species. Most remarkably, the text of the book has proven, to date, to
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be completely indecipherable. Not only the language but even the apparent
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alphabet is something that has never been seen before. Statistical analyses
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of the words and symbols in the writing seem to be compatible with those
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of ordinary languages, but cryptographers have been stymied in their at-
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tempts to interpret the text as some kind of code. It may be a very good ci-
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pher; it may be a unique language that was invented by an individual and
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then forgotten; or it may be a complete hoax.
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Does the Voynich manuscript contain information?
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An excerpt of the writing that appears in the Voynich manuscript.
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One is tempted to say that it depends on the origin of the book. If it
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really is a hoax, and the words are some kind of semirandom nonsense, then
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perhaps it doesn’t contain much information at all. But if it is merely a
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clever code that will someday be broken, it might contain a great deal—
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even if that “information” is purely a work of imagination.
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What if the Voynich manuscript is a code that will never be broken?
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What if it was originally written with very specific intent, but its meaning
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has been so well hidden that nobody will ever be able to reveal it? Does it
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stil contain information? What if the manuscript is placed in a capsule and
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launched into space, and then the Earth is destroyed by a cataclysmic aster-
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oid impact, and the book floats through the void for all of eternity. Does it
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contain information then?
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We tend to use the word “information” in multiple, often incompatible,
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ways. In chapter 4 we talked about conservation of information in the fun-
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damental physical laws. There, what we might call the “microscopic infor-
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mation” refers to a complete specification of the exact state of a physical
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system, and is neither created nor destroyed. But often we think of a higher-
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level macroscopic concept of information, one that can indeed come and
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go; if a book is burned, the information contained in it is lost to us, even if
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not to the universe.
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The macroscopic information contained in a book is relative to the en-
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vironment in which it is embedded. When we talk about the information
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contained in the book you are currently reading, what we mean is that these
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words are correlated with certain ideas that you get upon reading them. You
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read the word “giraffe,” and the notion of a certain kind of long- necked
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African ungulate appears in your mind. The same holds for the informa-
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tion contained in a strand of DNA: it is correlated with the synthesis of
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certain proteins in the cell. It is this connection with one configuration of
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matter (a book or a DNA strand) and something else in the universe (the
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image of a giraffe, or a useful protein molecule) that lets us talk about the
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existence of information. Without those correlations— if there isn’t, and