A favourite XKCD:
Made out of Meat
Here’s a few idle, Friday afternoon thoughts. I study distant galaxies. I use mathematical models of the laws of nature (and a supercomputer) to try to predict the properties of light emitted by and scattered through swirling vortices of matter, each containing a thousand trillion trillion trillion tons of stars, gas and dark matter, almost a trillion trillion kilometers away. My discipline – cosmology – has taken as its object of study the universe as a whole. And we’re doing pretty well, thanks for asking. I’d like to think that I am an evidence collecting, theory discovering, model investigating, equation solving (with a little help from my computer) machine.
And then I hear a talk from a biologist. I am reminded that I’m a fighting, fleeing, feeding, and reproducing machine. The lump of stuff in my head was produced by causes that “see” survival and reproduction. My brain is the control centre of a biological organism, and there seems to be precious little overlap between survival, reproduction and astrophysical ability. (Unless my astrophysical brain has made me so attractive to the ladies that it significantly increases my chances of reproduction. I’ll ask my wife.) An accurate mental picture of the world, formed using mostly reliable senses and the ability to reason logically, creatively and flexibly, seems useful to survival. But to use a brain to do cosmology? Really? (If you haven’t read Terry Bisson’s wonderful short essay “They’re made out of meat“, then do it now: “Thinking meat! You’re asking me to believe in thinking meat!”.)
A parable. Suppose I call Toyota customer services.
Me: Hi there. I own a 1993 Toyota Camry. I have a question.
Toyota: Certainly, sir. Is the car running well, getting you from A to B in comfort?
Me: Sure. It’s doing all that nicely. I was thinking about using it to drive to the moon.
Toyota: … Right … Wouldn’t recommend that, Mr Barnes. No … uh … not really in the user manual, I’m afraid. Not what it’s made for.
Suppose I find a customer support label on the back of my brain.
Me: Hi there. I own and operate one of your brains. I have a question.
Support: Certainly, sir. Is it operating your body, correctly? Are you getting enough food? Have you found a mate?
Me: Sure. It’s doing all that nicely. I was thinking about using it to do theoretical physics, discover the fundamental laws of the universe and use them to understand the structure and evolution of the universe and all its contents.
Support: … Right … Wouldn’t recommend that, Mr Barnes. No … uh … not really in the user manual, I’m afraid. Not what it’s made for.
Let’s be clear about the point I’m making here. I don’t doubt that physicists in general and cosmologists in particular have discovered true facts about the universe. It’s just a tad amazing that we can do that sort of things with our brains. (We use computers and telescopes as well, of course, but they too are the products of human brains). To extend the analogy, it’s as if I find myself standing on the moon, wondering how I got there. And as I look around, all I can see is a 1993 Toyota Camry. It’s not that I doubt where I am; I’m wondering how I got here in that! I’m not asking: how do I know that our investigation of the universe is successful? I’m asking: why is our investigation of the universe successful? How does fighting/fleeing/feeding/reproducing machine manage to do theoretical physics?
Perhaps the boring answer is the right one: we do it bit by bit. If we view science as extended and refined common sense, then maybe we can understand how a brain “made for” understanding local terrestrial environments is able to understand the universe. We don’t directly grasp the universe, of course. We rely on mental pictures and analogies. Mathematical models of the universe are perhaps analogies with equations. Having a mental picture of the world is useful. Just add curiosity and get practicing.
It seems like the same problem arises for mathematics – how does a brain manage to investigate such abstract ideas as those of pure mathematics? The same answer suggests itself: abstract thinking is useful. Just add curiosity and get practicing.
The universe is easy
We seem to need another ingredient in this explanation. That a brain can do theoretical physics and cosmology suggests not only that it is a remarkably adaptable, programmable thing, but also that the universe is an easier problem than we might have expected. A great example of this is the so-called cosmological principle. (I discuss this in more detail in my Australian Physics article here.)
That the universe is rationally analysable at all, that there is order and reason waiting for us in the mathematical structure of the universe, is a remarkable fact. The intellectual problem we are presented with in nature is, in a very real and precise sense, solvable. It is one thing that the universe exemplifies such beautiful mathematics as Lagrangian dynamics; it is another, a fortiori, that the Lagrangians that describe our universe display numerous and deep symmetries. The universe is a complicated place, and the mathematics that describes it must be complicated at some level. The remarkable thing is that the complication is on top; there is simplicity underneath. To be more precise, the laws of nature are simple, their solutions can be complicated. Newton’s law of gravitation is simple, but for even three bodies, its solution cannot be written down analytically.
In physics’s search for the ultimate laws of nature, many physicists wouldn’t accept a proposed fundamental theory unless it were simple, elegant, and beautiful. Paul Dirac went so far as to say that “it is more important to have beauty in one’s equations than to have them fit experiment”. It follows that physics cannot explain why the laws of nature are simple, elegant, and beautiful. Now there’s a thought for the weekend.
Letters to Nature 
Well, I’m just a little less amazed at all this than you are. For one thing, only a small fraction of all people are capable of investigating abstract ideas. For another, even those people are actually pretty bad at it. After all, there have been people for two million years, but it’s only the last 300 or so that we’ve made any significant progress about understanding the universe. A little historical perspective is useful.
Also, your puzzlement with the “simple” and “elegant” laws of nature seems a little misplaced. After all, there are many aspects of mathematics, chemistry, and physics that are neither simple nor elegant. Maybe we’ve found the simple and elegant aspects *first* because they’re, well, simple and elegant. But if some aspects were complicated and inelegant, we might not find them so quickly.
“small fraction of all people” … I don’t see the relevance. That any brain can do cosmology, given that they are all reproducing-machine-operators, is at least noteworthy.
“People for two million years” – but the brain is still a biological organ. Two million years of practice at feeding and reproducing won’t necessarily make a theoretical physicist.
“many aspects of mathematics, chemistry, and physics that are neither simple nor elegant.” Let me quote … myself on this one: “The universe is a complicated place, and the mathematics that describes it must be complicated at some level. The remarkable thing is that the complication is on top; there is simplicity underneath.”
Nice. Only then we have to explain the missing ingredient: “curiosity”. I mean the kind of curiosity that compels us to venture beyond what seems useful (maybe rightfully so) – this *could* actually have evolutionary benefits, but also could be a dangerous characteristic. On a population-wide scale, having a few curious scouts benefits the whole tribe, but sometimes those scouts decide to go to the moon.
“Why do humans do science? Why do they do art? The things that are the least important for our survival, are the very things that make us human.” – Savas Dimopoulos, Particle Fever
John Keating: We don’t read and write poetry because it’s cute. We read and write poetry because we are members of the human race. And the human race is filled with passion. And medicine, law, business, engineering, these are noble pursuits and necessary to sustain life. But poetry, beauty, romance, love, these are what we stay alive for. To quote from Whitman, “O me! O life!… of the questions of these recurring; of the endless trains of the faithless… of cities filled with the foolish; what good amid these, O me, O life?” Answer. That you are here – that life exists, and identity; that the powerful play goes on and you may contribute a verse. That the powerful play *goes on* and you may contribute a verse. What will your verse be?
Thought-provoking – I like your Toyota analogy. Your blog reminds me of these well known quotes by Nobel prize winners:
Albert Einstein: “The most incomprehensible thing about the world is that it is comprehensible.”
Eugene Wigner: “The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve.”
Hello Dr Barnes
In regards to the physical laws which govern them, is it true that anything described by them can be in a state different from what it currently is in or what it was once in such as a quantum vacumm which gave rise to our universe? If this is true would;nt that make it impossible for there to be a fundamental theory for physics as if the above is true everything we know in physics could have or have had intrinsic properties different from what it currently has or had? If so would the laws really be as simple and elegant as we think?
“Meat machine?” Neurons are not muscle cells. Neurons share a trillion different connections with other neurons in the brian, and electricity passes between them. They also have memories and learning capabilities. Rat neurons taken from rat brains trained themselves to drive an electric car to ensure it avoids hitting walls. The rat neurons were in a Petri dish, but hooked up wirelessly to a small car with wall sensors and drive capabilities, and the neurons were rewarded with a little extra jolt of electricity whenever the car avoided walls. Soon the neurons in the Petri dish were avoiding walls more and more often. Neurons are adaptable as to what they can learn.
Discoverability is no great mystery once you consider that we did not come into the cosmos, we came out of it, so it is kind of like the cosmos has evolved a teensy bit of self refelction. Also all maps, like all words and mathematical models do not equal reality. Our brains model reality, and no single human mind contains the cosmos. Whatever knowledge we have could vanish tomorrow with the fall of civilization or extinction or devolution of our species, or even the replacement of our species with a newer model tha looks back at ours as we look at apes, or with the development of AI that can learn to upgrade itself faster than human programmers can.
It is true that many species do not require large brains to survive, and in fact very few species require the kind of extra large brains found only in such mammals as elephants, great apes (including our species, which looks like it will soon be the last great ape standing), or the Cetacea (whales, dolphins).
But once the earliest brains and sensory organs began to appear in nature one can see the possibilities of at least a few species developing in the direction of more intense feedback, and one can also see that trunks in the case of elephants, and fins in the case of the Cetacea might not lead further, ah, but the great apes with free and nimble fingers, could go further still via the benefit of writing down lessons learned by previous generations.
Of course the price paid by the countless other species who evolved in differing directions over time just so at least one great ape might be left standing in the end was quite a lot of misses when it comes to aiming specifically at extra large brains. That is, if that WAS the aim.
Looking at the book, WTF EVOLUTION, I am uncertain there was such a specific aim, since this cosmos resembles an experiment in perpetual variety rather than a focused attempt at hitting a specific bull’s eye. looking at the countless stars and wandering worlds out there, and energies flowing to and fro, and atoms fused inside distant stars to form increasingly more different kinds of atoms, and them molecules continually bumping into one another, throughout the cosmos, it looks like e large experiment just to see what may happen. Nor can we be sure the experiment has been completed with our current model of the last great ape standing. since the stars can continue to shine for billions more years, and in some places they are still arising en masse.
I have two pieces online that address questions of cosmic and cerebral complexity, as well as the brain-mind’s ability to think logically and mathematically. Both of these pieces, after some preliminary discussion, wind up focusing on the lattermost question:
http://edward-t-babinski.blogspot.com/2011/01/prior-prejudices-and-argument-from.html
http://edward-t-babinski.blogspot.ae/2015/06/complexity-is-how-cosmos-flows.html
A third piece discusses the odds of you becoming you in particular, and of our species arising in particular, even of this cosmos arising in particular, and why the evidence appears to point to a Divine Tinkerer at best, not e most straightforward kind of Designer. A Divine Tinkerer seems a completely sufficient explanation for the evidence from nature that I share in that post. But if a Divine Tinkerer explains the cosmos and living things, then maybe trial and error and natural selection are also sufficient explanations. You pays your money, you takes your choice:
http://edward-t-babinski.blogspot.com/2015/07/can-fine-tuner-admit-that-their.html
Cosmology is an aspect of culture. I have a stab at “What is culture for?” in http://grampsgrumps.blogspot.com.au/2015/02/what-is-culture-for.html. Not, unfortunately, quite what one might like to hear.