Tuesday, July 19, 2016

Reply to Bonnie on Evolutionary Explanations

Bonnie’s recent comment involved more than the topic of the last post.  To provide the context for the rest of the comment, my friend Ron posted this:
The problem with all teleological explanations is that many natural phenomena pursue multiple purposes. Although the "purpose" of the human eye is to see... we all look at each other's eyes to form judgments about personality... especially reproductive judgments. The Roman Catholic Church is especially intent on assigning reproductive purpose to monogamous marriage while ignoring friendship as a goal. THUS the question of whether one purpose is more "ultimate" than another purpose is often contingent upon contextual considerations.
This was in response to my recent post explanation and teleology2. I replied as follows:
If by ultimate we have in mind the proximate/ultimate distinction, it seems easy to sort out in case of eyes. Their ultimate function is clearly vision. This is powerfully reinforced by the observation that eyes are temporally and genetically prior to human eyes. Our ancestors had eyes long before the human species emerged.

That we have large whites around our corneas may be an adaptation. It allows us to tell when we are looking into one another's eyes and so facilitates communication. Since chimpanzees don't have such eyes, it is very probably a recent adaptation as runaway selection for intelligence and cooperation shaped our species. At any rate, it seems quite easy to assign these various features to primary and secondary functions.

I won't speak for the Catholics, but Aristotle (who has some purchase with them) also recognized reproduction as the primary function of marriage. This seems to me to be obviously true. It doesn't obviate (in fact it may comprehend) the function of friendship.
Bonnie in turn as this:
On eyes the ultimate (why) final cause of eye as vision could include seeing material objects and forms in the world. If one has an affinity with the poetic understanding of eyes as windows to the soul there are other questions. The ultimate evolutionary purpose of the white of eyes as an adaptive mechanism is purely speculative theory unless tested by scientific method. The science that studies sight at the most refined level is neuroscience.
I reply that the final cause of eyes as vision devices obviously includes seeing material objects and forms in the world.  Cats are looking for prey and prey are looking about for cats.  To test this, I need merely observe the cats and rabbits in my back yard.  The cat moves very slowly, because sudden movement is more visible to rabbits.  The rabbit responds to the cat by freezing, because movement is more visible to cats.  I am sure that the eyes of cats and rabbits are windows to their souls.  Most of what their souls are about is eating and not being eaten. 
What happens in human beings is a lot more poetic, I suspect; but then I am not a rabbit.  When I look at a painting by Joseph Turner, I am not trying to survive or mate.  I am pursuing beauty, which my evolutionary heritage has allowed me to pursue because all the necessary things have been provided.  My agenda is not the same as the agenda of my genes.  Much the same thing is happening when I watch the rabbits play with one another.  They leap at each other and seem to dance.  This may have some adaptive function, but it looks like simple fun.  A cat toying with a mouse is another example.  Good training for hunting, most likely; but a lot more fun for the one than the other. 
Yes, it is speculative that the large whites of human eyes may function to facilitate communication.  It is much easier to tell if a human being is looking at me because I can see the direction of her gaze.  Evolutionary explanations can rarely be tested in the same way that water can be tested for bacteria.  Mostly we have to make do with reverse engineering.  Why the large whites of the eyes?  It might be an accident of eye evolution.  Even if it is, that doesn’t mean that it wasn’t adaptive for another purpose once it was in place.  It might be adaptive for another reason, but the same holds.  All we can say for sure is that it doesn’t look like a complete accident that a species that benefits from interpersonal cooperation has eyes that allow one individual to tell when another is paying attention to her. 
Finally, there is this comment:
If the Greek translation of Aristotle’s ultimate theory carries any weight one might leap to conclusions about the composition of genes. In this era of biotechnology that is a big deal. The courts have wrestled with the question AMP v. Myriad 2013 and have settled upon a kind of genes are like chemistry analogy. It serves Occam’s Razor to simplify its work in resolving disputes between corporate and others interests. According to this analogy the simplest explanation is that genetic information is linear and their coded information is deterministic. Research scientists whose motives exclude the allure of profit and fame as primary incentives, increasingly theorize that a better analogy for the behavior of genes is more quantum physics. Their actions are less predictable than the simplified linear understanding that applies to chemistry. If I am correct, this fits Ron’s remarks about contextual influences.
I have been aware of this for a long time.  Since the discovery of genes, it has been tempting to believe that genes are legible: each codes for one trait and the code can be deciphered.  Once we decipher it, we can edit the code to produce the traits we desire.  I don’t think that anyone in the relevant fields believes that there is a simple, deterministic relation between genes and traits.  A single gene may code for many traits in the body, from the brain to the brawn.  Moreover, many genes depend on environmental inputs for their operation. 

Our genes code for flexibility.  When a cat decides whether to chase a rabbit or a fisherman whether to cast his line, each is making choices.  As I have argued in these posts, evolution works through animals by allowing each to pursue its own agenda.  A bull elk in a rut is not trying to produce the next generation of elk.  He is trying to beat the snot out of other bulls.  When I make dinner for my wife, I am not trying to get my genes into the next generation.  I am trying to make her happy.  That is how the beautiful emerges from the merely necessary.  

Reply to Bonnie on the Aristotelian Soul

Dear friend and frequent interlocutor, Bonnie, posted a long comment connected with this blog at the International Political Science Association Research Committee 12 Facebook page.  I am replying here. 
Others whose scholarship has focused on Aristotle propose that the Latin version of Aristotle differs from the Greek in ways that are significant for biology. For instance the concept of soul (psyche) about which Aristotle wrote in De Anima in Greek means breath (or life). The Latin Aquinas proposed that soul is autonomous and independent of the body. Thus a shift of that kind implies dualism in Aquinas translation of Aristotle that was not included in the Greek. Ken you know far more than me so correct any misunderstanding…
John Herman Randall, a great scholar of Aristotle who taught at Columbia where another friend of mine studied philosophy, taught that the Greek version of Aristotle is a kind of process philosophy. One small example of a translational conundrum is that the concept of soul (psyche) in Greek means breath (or life). The Latin Aquinas understood soul as autonomous and independent of the body. Thus, Aquinas’ translation of Aristotle leads to a dualism that, according to Randall, does not appear in the Greek Aristotle.
I cut and pasted out of order to focus on this central point.  I am marginally competent in classical Greek.  I have no Latin.  For a number of reasons however I do not think that the translation of Aristotle’s word for the soul‑ψυχή‑into the Latin anima was responsible for a more dualistic concept of soul. 
All words for soul are grounded in the distinction between the external, visible aspects of beings and the internal, invisible dimensions of those beings.  The soul explains two basic phenomena: why some things are alive rather than dead and how human beings and animals (and perhaps even trees or fresh springs) can have an internal consciousness and intention.  That these phenomena are real in the case of human beings we know firsthand.  That they are real in animals we know from analogy.  As for plants and sacred mountains, I remain agnostic. 
As soon as a culture becomes aware of this distinction between the visible and invisible aspects of the human being, it is almost inevitable that someone will imagine that they can exist apart from one another.  What, after all, is a corpse but a body from which the soul has departed?  If the soul departs, where does it go?  Perhaps it is as the Buddha suggested with his powerful question: where does the candle flame go when it is blown out?  The Greeks and the Romans certainly imagined that there were realms where souls exist without bodies.  I seem to recall Achilles complaining about the lodging in Hades.  Moreover, ghosts are ubiquitous in all cultures that are aware of the body/soul distinction. 
Philosophical accounts of dualism are another thing.  To my knowledge, the closest one comes to dualism in classical philosophy is Lucretius’ reading of Epicurus.  Lucretius is one of the rare examples of a genuine materialist.  All aspects of real beings are the consequence of their atomic components.  The soul, he supposed, was fine, invisible cloud of particles that escapes from the body at death like air from a balloon.  I suppose you will find more in the Neoplatonists; however, whatever they were, they weren’t Platonists. 
Aristotle’s account of ψυχή is not at all dualistic.  He says that the soul is the actuality of a body with potential for life.  To unpack this, ask yourself “what is a church?”  It’s not the bricks and boards, for these could have easily been assembled into a bank or a brothel.  It’s not the completed building, for a church has to have people and the building could be just as easily used by the bankers or the working girls.  The church is a group of human beings gathering together to do something, in this case, to worship.  Likewise, an Aristotelian animal is a specific kind of matter, organized in a certain way, and actually doing certain kinds of activity: breathing, metabolizing, sensing, etc. 
Aristotle’s soul is quite complex.  It encompasses three distinct explanatory causes: the species form (it’s a cat and not a catfish), efficient causation (the form is constantly pushing it to grow, feed, etc.), and final causation (the form directs the growth and activities of the organism towards certain ends).  It is very difficult to imagine how this kind of soul could exist apart from a material body.  To deploy a simpler analogy, a bowl has to have a convex shape; that means, however, that something must exist to be shaped into a bowl.  You can’t pour milk over cereal contained in an abstract geometrical form. 
I have read enough Aquinas to be astounded at the power of his thought.  I don’t know him nearly well enough to comment on his view of this matter.  I do know the New Testament and I read in the wee books at the end that Jesus was come in the flesh.  This was the result of a long struggle between the early church and the Gnostics.  The latter believed that all material was vulgar and bad; what was spiritual and good could exist only in the spirit.  So if Christ was the son of God, then he must have existed in spiritual form alone.  To this 1st John 4:3 says:
κα πν πνεμα  μ μολογε τν ησον Χριστν ν σαρκὶ ἐληλυθτα, κ το Θεο οκ στιν κα τοτ στιν τ το ντιχρστου, ὃ ἀκηκατε τι ρχεται, κα νν ν τ κσμ στν δη
And every spirit that confesseth not that Jesus Christ is come in the flesh is not of God: and this is that spirit of antichrist, whereof ye have heard that it should come; and even now already is it in the world.
I find it fascinating that the early church was fighting explicitly against the dualism of the Gnostics.  Furthermore, to my knowledge, all major Christian churches confess the resurrection of the body.  Our souls don’t float off to heaven.  When we gain resurrection, we get our bodies back.  I am hoping for two things.  One is that the standard of admission, when it comes to opinions about these things, is lax.  The other is that I will be a bit taller and that I can sing. 
I don’t know what the nature of life after death might be but I agree with Aristotle’s model of the soul and I think that it is incoherent to imagine a human being without a human body.  The notion that the soul is a vaporous self that can float away from the body after death (or maybe from time to time during life) is probably what most contemporary Christians believe; however, that owes more to Descartes and his dualism than to the history of the Church or its doctrines.  The soul as milky, transparent self is what I like to think of as the Gospel according to Walt Disney.  It is easy to imagine a dog soul with tiny wings and a halo just as it is easy to imagine a centaur.  Both are logically incoherent. 

Nor am I convinced that all dogs go to heaven.  My mother-in-law had a dog that came straight from Hell and, gracefully, went back.  I am pretty sure that most dogs go to heaven.  

Friday, July 15, 2016

Explanation and Teleology 2

Teleological explanations are appropriate when some process can be understood only by the end at which it aims.  Such a process necessarily involves the possibilities of success or failure: the end may be achieved or not.  The most obvious examples are those of human production.  A farmer plants seeds in order to produce a crop.  It may rain just enough, or too little or too much. 
Yet much the same thing seems to be true of the seed itself.  It sprouts and the sapling breaks the soil.  It is obviously trying to do something, to reach the sun.  If it is strong and conditions are favorable, it will flourish; if not, it will wither and die. 
The great philosopher of biology, Ernst Mayr drew a distinction between teleomatic and teleonomic processes.  As an example of the former, drop a stone into a well.  The beginning predetermines the end.  The stone will end up on the bottom.  That doesn’t mean that the stone is trying to get there.  Its irregular course is entirely determined by its weight and shape and the accidents of the water.  That is a teleomatic process. 
The growth of a plant is very different.  Consider a vine growing up a wall.  If you watched it in stop motion you would see that it is very deliberately climbing.  It twists around this way and that looking for a purchase.  When it finds one, it takes hold and climbs again.  The vine has a program that determines its action.  The program directs it toward something: the sun, perhaps.  That is a teleonomic process. 
Is it possible that we are only anthropomorphizing?  Perhaps we are only projecting our own purpose driven actions back onto nature, as when people think that the volcano blew its top because the gods are angry.  Here is a counter example: years ago when I walked up to campus I noticed snowflakes falling on my arm.  They were perfect little six point stars made of two intersecting triangles.  I paused to wonder if God were telling me something.  The Jews are right! 
Maybe they are.  About a lot of things.  I think, though, that the “program” that determined the form of the snowflake was nothing other than the structure of the water molecules behaving according to the circumstances.  That is a teleomatic process, nothing more.  How then does the climbing vine differ?  It too takes form according to the complex molecules that it inherited. 
Here evolutionary theory kicks in.  Snowflakes do not give birth to other snowflakes.  The production of a six pointed star on a winter day does not result in a lineage of six pointed crystal stars with parents and grandparents.  By contrast, the vine has parents and will, if it is successful, have offspring.  Without understanding that, you cannot understand what a vine is. 
I suspect that the lineage is an essential element in the definition of life.  If this were all there were to it, teleological explanations would be reduced to the successful extension of biological lineages.  That may indeed be true of most of the organisms on our world.  However…
At some point evolution produced sentient organisms.  This kind of creature can respond to its environment in a much more flexible way than vines.  It has a robust kind of freedom: it can move this way or that, snatch or flee.  Natural selection favored those creatures that acted in ways that promoted successful reproduction.  Since they had an element of freedom, it had to work by bribing them with pleasure and punishing them with pain.  These existential elements function to select behaviors that promote successful reproduction without paying the cost of death. 
Now we have a telos that is distinct from the simple evolutionary telos.  A plant either flourishes or withers.  Its only rewards are saplings; its only punishment, no saplings.  An animal can flourish and yet be miserable.  Animals act for the sake of what pleases them and to avoid what displeases them.  They have an existential stake in their lives. 
Human beings represent the most advanced stage of this evolutionary trajectory.  Whereas all the other animals can tell the difference between what they like and what they do not like, human beings alone can distinguish between what they like and what is really good for them.  This capacity is amazing, but not without robust biological roots.  It arises out of a capacity for building internal, mental models of the external world.  This feature of animal life is ubiquitous. 
There is a species of spider that makes its living by feeding on other spiders.  To hunt it climbs high by spider standards among leaves, or at least high by spider standards, and looks out for prey.  In order to attack its prey safely, it has to come up behind it.  To do that, it has to climb back down to the floor and climb up again in a route that will allow it to come up in a strategically favorable position.  To do that, it has to build a map of the general route. 
Internal mapping of the external environment is a very profitable strategy.  Very simple organisms have to try the same trick every time and live or die depending on whether it works this time.  More complex organisms can try different tricks, but only find out what works by testing it in perilous conditions.  Creatures capable of internal mapping can try it first in the safe environment of the map, thus avoiding a lot of dangers and saving precious energy. 
Anthropoi are, if nothing else, very sophisticated internal mappers.  It is one reason that we spend some much of our time living in our own imaginations.  It allows us to build pyramids and send probes to see whether the planet Jupiter has a solid core or not.  It also allows us to choose not to eat a big bag of pork rinds even though we would really enjoy that.  The moral dimension emerges when we began to distinguish between what we want to do and what we ought to do.  That, almost certainly, was a product of our evolution as political animals.  We became very effective cooperators because we were able to resist the temptation to cheat one another, more or less, enough for government work.  Our mapping software includes a lot of prepackaged apps for getting along with other people, for demonstrating that we are good partners, for detecting when someone else is not. 
Teleological explanations applied to human technology and those directed toward biological phenomena are in one sense the same and in another different.  They are the same in the sense that they emerge in evolutionary history due to the same dynamics.  We learned how to build dwellings for the same reason that ants and bees did: to survive.  They are not the same in the sense that we are pursuing ends that are not reducible to mere biological lineages.  Like any other animal, we pursue comfort and satisfaction directly and serve our Darwinian interests only indirectly.  Unlike any other animal, we are capable of genuine happiness.  We can achieve a life that is consciously satisfying, in a broad awareness of who we are and what we want. 

It was long assumed that Aristotle was illegitimately anthropomorphizing when he introduced teleological explanations to his science of nature.  Darwinian biology shows that he was legitimately anthropomorphizing.  Because human powers of thought are the products of evolutionary history, they are the best information we have about evolutionary history.  

Wednesday, July 13, 2016

Explanation and Teleolgy 1

I have been reading Mariska Leunissen’s Explanation and Teleology in Aristotle’s Science of Nature.  I am just getting into it, but it looks to be the best book on the Philosopher I have read in years. 
What got me thinking tonight is Leunissen’s discussion of the analogy between teleological explanations applied to natural and artificial production.  An example of the former would be the production of an oak tree out of an acorn.  An example of the latter, the production of a table out of oak boards.  Leunissen points out three aspects of this analogy:
First, in both cases the means or intermediate steps are complementary and adjusted for the sake of producing the end product.  The sprouting of the sapling and the planning of the wood are both guided by the end that the processes is aiming at. 
Second, both are cases of specialization.  Acorns produce oaks and not oats; wood wrights, acting in that capacity, may produce tables but not tablet computers. 
Third, production is reliable in both cases.  When supplied with all the necessary conditions (there is plenty of room for failure and accident), both the acorn and the wood wright will achieve their purposes. 
What is most interesting to me in this is the second point, for it connects Aristotle’s understanding with the evolutionary account of the history of life.  The diversity of life is largely a result of specialization of function.  Indeed specialization is a synonym for adaptation in this case.  Some creatures are very specialized.  They can exist in only very specific environments and perhaps eat only one kind of food.  Other creatures are extraordinarily flexible, able to respond in distinct and adaptive ways to a wide range of environments.  Human beings are, very probably, on the extreme end of this scale. 
It is probably the case that the earliest forms of life were very specialized.  Each reproductive act resulted in an almost identical organism adapted to a very local environment.  Such organisms could respond to changes in the environment or migrate to different environments only when their lineages diverged into new forms by means of mutation and natural selection.  Organism A for environment A; organism B for environment B, etc.  All organisms must be responsive to their environments; however, the only means such organisms as these had to test their forms was by life and death. 
At some point organisms emerged that could alter their behavior and even their forms in more significant ways in response to changes in the environment.  Such organisms could find the successful behavior by trial and error, rather than simply perishing or not.  That means that they became capable of multiple specializations.  I see the result of this in my backyard.  When I walk out, a rabbit will respond first by freezing.  That’s one specialization.  If that doesn’t seem to work, she will run like Hell.  That’s another. 
I think that this allows us to place human arts within (or at one extreme of) the spectrum of evolutionary history.  A wood wright specializes in wood work; however, he specializes in a lot of other things as well.  He specializes in communication with other human beings, in living in a particular climate, etc.  He may specialize in physical fitness if he spends a little time in the gym.  We are generally good at specializing. 
Natural reproduction is much more restricted.  Human couples specialize in producing human infants more or less like themselves.  To be sure, environmental factors will affect the offspring, even in the womb.  Some of these responses may be adaptive, though most that we know of are not.  For the most part, with respect to natural production, we are in the same boat as the Ur organisms: our offspring survive or they don’t. 

The value of joining Aristotle’s approach with that of modern biology is that it breaks down the barrier between the arts and sciences and the flowering of natural organisms without reducing the one to the other.  Culture and nature are not two distinct realms.  Culture is a product of the human capacity for multiple specializations and that is the most remarkable result of the evolutionary expansion of organismal forms into the design space that was available for them.  Aristotle’s analogy shows why we need not draw a wall of protection between the human things and nature.  

Friday, July 8, 2016

Aristotle Saves Biology

I confess that I did not know, until tonight, that Aristotle understood precisely what a lunar eclipse is.  This is rather significant, because I had generally assumed that Aristotle’s physics was entirely indefensible.  While I am now on solid ground in holding that is biology is mostly solid ground, what of his view that a pitched falls back to earth because its earthy nature compels it to return to its natural place?  Aristotle did not have a reliable theory of momentum.  But then I came across this passage in the Posterior Analytics
τί ἐστιν ἔκλειψις; στέρησις φωτὸς ἀπὸ σελήνης ὐπὸ γῆς ἀντιφραξεως
Pretty straight forward, no?  Here it is in English.
What is an eclipse?  A deprivation of light against the moon due to the obstruction of the earth.
That is dead spot on, which is astonishing for his time.  He even goes on to say that this explanation, which relies on speculation, would be directly apparent if we were standing on the moon.  We would see the earth moving across the sun.  I am not going to try to rehabilitate Aristotle’s astronomy; however, I can’t help pointing out that, in considering the same event from two different points in space, he is perilously close here not only to Newton but to Einstein. 
I was reading the PA because I read a very fine paper by Lucas Mix: “Nested explanations in Aristotle and Mayr,” in Synthese (2016) 193: 1817-1832, and Mariska Leunissen’s book Explanation and Teleology in Aristotle’s Science of Nature.  Leunissen points out that Aristotle’s explanatory strategies may help us resolve certain fundamental problems in the modern philosophy of biology.  This is what Mix tries to do in joining Aristotle with Ernst Mayr, two of my favorite philosophers of biology. 
Modern biology involves a host of evolutionary and organismal explanations that cannot be generated by physics and chemistry alone.  Chemistry can tell you a lot about the DNA molecules but it cannot explain what a gene is, let alone make sense of organisms, adaptation, end-directed processes, etc.  At the same time, all biological phenomena depend on the mechanical laws of physics.  All organic activities, from metabolism to mental gymnastics require the expenditure of energy and fail when the energy runs out; yet only organisms can succeed or fail at anything.  How are we to understand the relationship between these two domains of science?
Here is how Mix puts it:
Nested explanations provide the most utility for biology. Good evolutionary explanations involve natural selection acting on replicating physical systems; therefore, the fullest biological knowledge will appeal to an evolutionary explanation nested within a mechanical explanation (or series of explanations). The evolutionary explanation is etiologically prior; it defines the categories in question (functions, organisms, genes). The mechanical explanation is temporally prior; it includes the material from which they are made and the rules by which they interact.
To say that evolutionary explanations are nested with mechanical explanations is to say they are a very special case of mechanical explanations.  Some physical systems have nothing to do with the former, as in the case of volcanoes.  Other physical systems like redwood trees cannot be understood without the former.  To say that the evolutionary explanation is etiologically prior to the mechanical explanation is to say that one must approach the study of living organisms with a basic understanding of what they are and that this is something that mechanical explanations cannot provide. 
Here is my take, for which Mix bears no responsibility.  The relationship between the mechanistic sciences, which ask only how something happened or is what it is, and the life sciences, which ask why something happened or why it is as it is, is analogous to the relationship between the Oxford English dictionary and a good English grammar, on the one hand, and Shakespeare’s Richard the Third on the other hand. 
Ignoring poetic license for the moment, Shakespeare was limited to a specific number of letters, a large but finite vocabulary, a large but finite number of grammatical rules, as well as a brevity dictated by the realities of the stage.  Given those restraints, an astronomically vast but finite number of plays was possible.  If you don’t believe me, read Jorge Luis Borges’ famous story, “The Library of Babel.”  It’s a good but sad joke to say that all one needs is a dictionary because all the other books are in it.  To get Dickey Three out of the OED, among the vast alternative populations, you need Shakespeare. 
To get William Shakespeare out of the vast possibilities that the physical kosmos offers, you need what?  It is hardly clear.  We have no good idea how life arose out of the chemical soups, sunlight, and lightening scoured landscapes that the earth offered just before it began to fruit.  Fruit it did, and the playwright known as natural selection has been scribbling furiously ever since. 
Just as an interpreter of Shakespeare must begin with the play and not the dictionary, so a biologist must begin with living organisms and not with the periodic table of elements.  Organic chemistry is organic first and chemical second.  Of course here the analogy breaks down.  The dictionary doesn’t tell you much about the play.  Chemistry and physics tell you a lot about living organisms.  Why are there a lot of animals here and not so many there?  Sunlight and temperature tell you a lot about why there are trees with certain kinds of leaves and that tells you why there are a lot of creates that eat the leaves and predators that eat the leaf eaters. 
I like the notion of nested explanations because it seems to reflect the most basic human reality.  We are nested within the biosphere on the surface of this planet.  We thrive on certain geographies and not so much or at all on others.  The biosphere is also nested in a larger range, but still only a sliver of the world.  Outside, there is the too cold or too hot and the empty silence. 
As Mix observes, Aristotle was good at nesting one kind of explanation within another.  He saw no contradiction between material and mechanistic causation, on the one hand, and the power of organic forms and teleological processes on the other.  He might have been the last great philosopher to be altogether comfortable with all the ways that science could offer for understand the physical and existential realities of our life on this world.  I must admit that I am a little uncomfortable with that. 

Discomfort drives the history of philosophy and science.  Still, both must continue to pursue the final view that will integrate and resolve all the problems.  Just right now, I am feeling some of Aristotle’s confidence.