Welcome to this week's edition of Isms. In a couple of posts, Scibling Alex Palazzo of The Daily Transcript has given two quite distinct views of what biology is about: information, and mechanism. In the first he argues that what is needed to build organisms is information, and in the second that biology is about machines, things that do work. I want to say that he is wrong about the first and right about the second, and moreover that they are contradictory ways of looking at the living world.
I've argued against informational metaphysics when it comes to genes before (see here and here). Let me reprise the argument or claim: information has no causal power. Instead, things that have properties have causal structure and information is a property of our semantics, not the world. So whenever we are talking about information in genes, we are really talking about their causal properties. The same argument applies to all aspects of living beings except when they are actually information processing systems, like brains.
But talk of "causal powers" is a bit vague, so we have to talk about this some more, and here Alex is right on the money. Living things are full of subsystems that take energy and do work with it, in the thermodynamic sense. What used to be debated about - whether life had some special metaphysical properties that ordinary matter didn't, a vital force - is now completely resolved in the negative. There is only physics and chemistry involved in what happens in living systems. There's not the slightest hint of debate over that by biologists. Life is what happens when chemical systems get to a certain stage of complexity, allowing them to reproduce. All this takes energy from chemical reactions. It's all physics, like it or not.
Now here's my conundrum. If to do work requires energy, and something like information cannot be uniquely defined in energetic terms (all information processing systems need to expend energy, yes, but not all energy expending systems are informational, on pain of triviality), then it simply cannot be that information is a causal notion. So Alex's two ways of looking at life are mutually inconsistent. Mechanistic views of biology do not sit nicely with informational views of biology.
Now, in line with my extreme Ockhamism (do not unnecessarily multiply entities in explanation), my solution is to embrace the one horn, mechanism, and to treat the other, informationalism let us call it, as an abstraction, something we put together when we can't do the work to provide particular mechanistic explanations. For instance, natural selection is not, in my view, a mechanism. There is no simple relationship between the energy expended and the fitness of organisms. In fact I am not sure that there is any principled relationship at all. But each case of natural selection involves a physical machine that does work better or worse (that is, more or less efficiently) than its neighbours, and so its progeny end up being more frequent among that population.
In simple terms, all natural selection involves a physical job of work, but there's no unique kind of work that gets you natural selection. Selectionist explanations in terms of fitness values are placeholders for the actual explanation; we know that whatever accounts for the fixation of some trait will have a physical explanation, and so we use these placeholders until, and if, we can give it. [Just to head off misunderstandings, we don't always use selectionist explanatory schemes. Sometimes the behaviour of the population is such that we use drift explanatory schemes. And neither are actual explanations, but rather they are explanation sketches.]
Monistic mechanism, or pure physicalism as I prefer to call it, is often demonised by those who think somehow there has to be more to it. Some "mind", some "structure", some "information", is needed to complete the explanation. But an Optimistic Induction here might be that we have successfully addressed most of the problem cases that supported that sort of dualism; we may arguably rely on the continued success of this "reductionism". But what we do not need is more dualisms. I end with a quotation from one of the fathers of the information revolution of the post-war years:
Information is information, not matter or energy. No materialism which does not admit this can survive at the present day. (Wiener, Norbert. 1948. Cybernetics, or, Control and communication in the animal and the machine. Cambridge, Mass: Technology Press: 132)
PS: I don't deny what Alex says about Intelligent Design and the irony of them appealing to biological machines. That's quite true and quite amusing.
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I beg to differ. A mind (such as yours) is indeed required to observe and remark upon this mechanism or physicalism, otherwise none of it might as well exist (and some physicists might say that it wouldn't).
John, I cannot completely agree with your statement:
"...Information has no causal power. Instead, things that have properties have causal structure and information is a property of our semantics, not the world...."
you then go on to say that
"...Living things are full of subsystems that take energy and do work with it, in the thermodynamic sense."
and later
"Life is what happens when chemical systems get to a certain stage of complexity, allowing them to reproduce. All this takes energy from chemical reactions. It's all physics, like it or not."
Information is a valid physical concept if used correctly: i.e. The Landauers principle says that to erase 1 bit of information irreversibly at least k ln 2 entropy should be increased and at least kT ln2 energy should be consumed, where k is the Boltzmans constant and T is the temperature of a thermal bath. Thus any physical process could, at least in principle, be formulated in terms of its information content (in bits) just as it could be formulated in terms of its energy or entropy. I do not know if such a formulation of a biological phenomena would produce useful 'information' (here used in the less well defined sense of knowledge).
Perhaps the term 'information' in English is beginning to suffer the same fate as 'theory', or 'impact'!
Strictly speaking none of our models of how natural systems operate are the "Truth" but simply tools to help us understand and predict how those systems behave. I partially agree with you in that life is not just information, but I also believe that the ideas of "information" and "information processing" are useful concepts in thinking about how living systems operate. When Craig Venter transplanted the genome of one bacterium into another bacterium, the chimeric organism eventually resembled that which is "specified" by the DNA component and not the cytoplasm - why? Sure you can reduce the system down to the physical laws, but another useful model is thinking about what the DNA itself specifies - a particular digital code of A, T, C and G. This genetic program specifies the production of certain RNAs and proteins. Now of course this can be equally explained through the lens of physics and chemistry but explaining it through the shorthand of information can be much more useful. Does a geneticist need to think about every eqyuilibrium or energy expenditure to understand how traits are passed down or why Venter's chimera turned out the way it did?
Perhaps not germane, but interesting. This is a link to a press release about using DNA to store information.
http://www.sciencedaily.com/releases/2008/02/080224150305.htm
I did address these issues in the previous post and discussion, but the simple responses are:
On the interconversion of information and entropy; if true, that makes entropy the crucial concept as it is a physical concept and I am a physicalist. But I alluded to the fact that you can't do the reverse - from a physical description (in this case of the thermodynamics) you cannot, without some other information, say what the information content of an arbitrary system is. Also, if true, then the notion of "information" as used in genetics (and biology in general) is unnecessary; if everything is information then nothing is particularly informational (and Alex's claim evaporates).
On the usefulness of the information metaphor - I never denied it. But that doesn't mean we can make grand pronouncements about the nature of things based on utility. That is exactly the error made by teleologists today - we find it useful to talk in terms of ends, and so the universe is composed of ends. There is no information in genes, although we find it useful to talk that way because that's how we evolved to make inferences.
In fact, models are abstractions in every case (even when they are made from rubber bands and levers, or hydraulics). Information is a property of the models, not the things. I repeat again, pleonastically: the map is not the territory, unless you are using the territory as the map. Lewis Carroll, please help us!
John said: "Monistic mechanism, or pure physicalism as I prefer to call it, is often demonised by those who think somehow there has to be more to it. Some "mind", some "structure", some "information", is needed to complete the explanation."
Is your point simply that there's stuff that obeys the laws of physics and nothing else? If so, I agree, but I don't think it's demonized because people think it's not true. If it's demonized, it's because it doesn't get you very far in biology. Saying "biology is all about information" might not be the whole story, but it's a lot more useful than "biology is physics."
On a related note, why do you allow that "the same argument applies to all aspects of living beings except when they are actually information processing systems, like brains" when I think it could be convincingly argued that cells are also information processing systems? Why is a brain an information processing system and a cell is not?
Seems like this goes back to Kant. There is no way to know the ding an sich (thing in itself), assuming such a thing is even real, so our information will have to suffice. That's all we have. To paraphrase Bohr, it is wrong for science to say what nature is. Science has to do with what we can say about nature. In other words, science is about epistemology (information) and not ontology. If you're a strict positivist, they're actually one in the same.
Your blog should definitely have the following warning:
"But I don't want to go among mad people," Alice remarked.
"Oh, you can't help that," said the Cat: "we're all mad here. I'm mad, you're mad."
"How do you know I'm mad?" said Alice.
"You must be," said the Cat, "or you wouldn't have come here."
I had in mind this:
The problem of course, is that the "map" is all we have. We can never see things as they truly "are", independent from us and our way of seeing. There is no birds-eye or 3rd person perspective - there is only the first person imagining him or herself in such a position. There is no way to prove that there even is a territory, and the map-territory relationship is also just a map in your mind. In fact, everything is a just map in our minds - except for the cartesian sense of our own existence. That is the only direct knowledge or "territory" we have. It actually takes a good deal of "faith" to be a strict physicalist. And we do have a word for a territory that can never actually be observed: imaginary ;)
Look I think that you are missing the point. Information, as far as I'm concerned is a concept - or if you will a shorthand for a system that contains a an array of elements each of which can perform a discrete reaction. In my mind information does not inhabit an alternative platonic world, but instead boils down to the laws of physics and chemistry. Now maybe I am using the word "is" a little too lightly, but in the end I believe that my concepts are all rooted in materialism.
Also I would encourage you to finish reading that first post, I basically pointed out that more insight can be (and is) achieved by studying the network of machines found within each cell as opposed to simply analyzing the information content of the genome.
Instead of saying "Yay" or "Nay" to information, why not distinguish between appropriate an inappropriate uses of the concept in biology? For example, in "On Protein Synthesis," Crick was very clear about the restricted sense in which he used the notion of information -- nothing metaphoric about it at all. In contrast, the loose equation of information with any kind of structure, from the arrangement of physical parts to abstract relations, is trendy, but not very illuminating.