Hybridization, not Darwin’s natural selection, explains why butterflies mimic each other?

May 17, 2012

Here’s an open access paper, just published in Nature online (May 16, 2012) , about whose abstract a friend writes to say, “You could request a full paragraph of explanation for each sentence.”

Well-known examples of South American butterflies mimicking each other’s wing patterns may be due – not to wing panel by wing panel natural selection – but to hybridization.

That would make more sense. Never mind the famous question “What good is five percent of an eye?” Well, some good.

A more important question for many life forms is, what good is looking only five percent less like lunch? Five percent of an eye may be useful; looking only five percent less like lunch is not likely to be. And it is typical of a Darwin-crazed culture that so many people accept the Darwinists’ sales job and so few notice the critical difference.

Paper:

Butterfly genome reveals promiscuous exchange of mimicry adaptations among species

The evolutionary importance of hybridization and Introgression has long been debated. Hybrids are usually rare and unfit, But even infrequent hybridization can aid adaptation by transferring Beneficial traits between species. Here we use genomic tools to investigate introgression in heliconius, a rapidly radiating genus of neotropical butterflies widely used in studies of ecology, behaviour. we sequenced the genome of heliconius Melpomene and compared it with other taxa to investigate chromosomal evolution in lepidoptera and gene flow among multiple heliconius species and races. Among 12,669 predicted genes, biologically important expansions of families of chemosensory and hox genes are particularly noteworthy. Chromosomal organization has remained broadly conserved since the cretaceous period, when butterflies split from the _bombyx_(Silkmoth) lineage. Using genomic resequencing, we show hybrid exchange of genes between three co-mimics, heliconius melpomene, heliconius Timareta and heliconius elevatus, especially at two genomic regions that control mimicry pattern. We infer that closely related heliconius species exchange protective colour-pattern genes promiscuously, implying that hybridization has an important role in adaptive radiation.

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Insane or Simply Wrong?

May 17, 2012

David W. Gibson asks some interesting questions in a comment to johnnyb’s last post. First, he writes concerning Darwinism: “How could it ever have come to pass that tens of thousands of the most intelligent humans in the world, after decades of detailed study, could STILL fall victim to the ‘transparently ludicrous’?”

In the second century Ptolemy devised his system of cosmology. In this system each planet moves along a “deferent” and an “epicycle.” The planet’s movement along these two paths cause it to move closer to and further away from the earth. For the system to work, the planets sometimes had to slow down, stop, and even move backwards.

Tens of thousands of the most intelligent humans in the world ascribed to Ptolemy’s cosmology from the publication of Almagest around 150 until well after the publication of De revolutionibus orbium coelestium in 1543.

But this system of deferents and epicycles is “transparently ludicrous” you say. And so it is in retrospect. Nevertheless it reigned nearly unchallenged for well over 1,000 years.

Here’s another example. Humorism. “This theory holds that the human body was filled with four basic substances, called humors, which are in balance when a person is healthy, and all diseases and disabilities result from an excess or deficit of one of these four humors. These deficits could be caused by vapors that were inhaled or absorbed by the body. The four humors were black bile, yellow bile, phlegm, and blood.” Wikipedia.

Humorism was the prevailing medical orthodoxy from the time of Galen (circa 150 AD). It was not definitively displaced until 1858 when Rudolf Virchow published his work on cellular pathology.

Your phrase “transparently ludicrous” comes readily to mind when we think about humorism now. Yet it was the prevailing orthodoxy among tens of thousands of brilliant medical practitioners for nearly 2,000 years.

At the end of your post you ask another question: “Centuries of scientific progress can only be explained by mass insanity. Does that work for you?”

Suppose one of Copernicus’ critics (and he had many; his theory was not accepted immediately) had said, “Hey Copernicus, “how could it ever have come to pass that tens of thousands of the most intelligent humans in the world, after 1,393 years of detailed study, could still fall victim to a theory of cosmology that, if you are correct, is transparently ludicrous?”

Or suppose one of Virchow’s critics had said, “Hey wait a minute! How could it ever have come to pass that tens of thousands of the most intelligent humans in the world, after nearly 2,000 years of detailed study, could still fall victim to a theory of medicine that, if you are correct, is transparently ludicrous?”

I will put it to you David. How should Copernicus or Virchow have answered those questions?

Finally you write: “Centuries of scientific progress can only be explained by mass insanity. Does that work for you?”

First, I don’t know where you get “centuries.” Origin was published in 1859. That’s 153 years ago by my count.

Second, “mass insanity” is a nice strawman. No one has suggested that someone who believes in Darwinism is insane. They are simply wrong.

Were all cosmologists from Ptolemy to Copernicus insane? No, they were simply wrong.

Were all doctors from Galen to Virchow insane? No, they were simply wrong.

The essence of your argument for Darwinism is: “All the smart people believe it; it must be true.” I hope you understand now that that argument is not as airtight as you seem to think it is.

Uncommon Descent

Epigenetics, game changer

May 17, 2012

In “Methylating Your Muscle DNA” ( Scientific American blogs, May 14, 2012), “Scicurious” reports,

We know that increases in methylation in muscle cells are associated with things like insulin resistance, so it’s possible that decreases in methylation could explain some of the protective effects of exercise. And it’s very interesting to see that the authors got changes in methylation after a single exercise exposure. Of course, it would interesting to see if these changes persist with chronic exercise, and whether caffeine ingestion in humans in normal amounts produces similar changes, but I imagine maybe the humans in these studies weren’t up for the biopsies. But it’s an interesting study, helping us begin to see how changes in the epigenome, caused by changes in our own behaviors, might begin to impact our health in the long term. It makes me want to go for a workout./blockquote> Uds too, and the workout might include dismantling tenured Darwinism.

The world of life just isn’t like what they say.

Uncommon Descent

From The Best Schools: Mad Scientists Then and Now

May 17, 2012

James Barham, here.

People are too big. If we want to save the planet, we must shrink ourselves.

That’s the message of a recent Atlantic article entitled “How Engineering the Human Body Could Combat Climate Change.”

The piece reports on a proposal—to be published soon in an environmental ethics journal(1)—to meet the challenge of climate change (if such it be), not by transforming the earth and its climate, as some have suggested, but rather by reengineering human beings themselves.

More. Yeah right. How many human beings have ever actually wanted to be shorter? Those of us who need tall hats and six-inch heels to get by socially are far more common.

Uncommon Descent

You can tell it’s an election year when…

May 17, 2012

Here: (Mercatornet, May 16, 2012)

Whether reproducible—on its own terms—or not, what makes this stuff bunk is: Voters’ reasonable interpretation of their own experience is dismissed as irrelevant.

(compared to stuff about evolution, neurons, or genes)

Does it matter? The main problem isn’t that this partisan nonsense is hurtful to conservatives, but that its emphasis on supposed hard wiring and emotion over context and reason is unlikely to be compatible in the long run with representative government.

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Uncommon Descent

Here is Evolution’s Version of the Multiverse

May 17, 2012

Physicists have come up with the idea that there could be an astronomical number of universes in addition to our own. They call it the multiverse it can explain very improbable events, such as the origin of life, because no matter how improbable an event, it becomes a virtual certainty when you have so many universes in which it might happen. This idea of separated worlds is now emerging in genetics as well, as some evolutionists are contemplating the idea of different DNA worlds. The evolutionary tree model doesn’t work very well, and so evolutionists are experimenting with other models. One is a network model and using it evolutionists have found that DNA sequences in nature tend to separate into different worlds. But unlike the different universes in the multiverse, these DNA worlds can have some limited interaction. This means that, as usual, evolutionary theory has gained a great many new degrees of freedom. Here is how the evolutionistssummarize their findings: Read more

Uncommon Descent

How to Talk to Your Professors About Your Darwin Doubts

May 17, 2012

There are two regular tragedies in the Intelligent Design movement. The first tragedy is the student who airs his or her doubts about Darwin, and a faculty member then makes it their life mission to block that student from a degree, or, if they get a degree, prevent them from getting any further. This sometimes happens via a bad letter of recommendation or a notice in their file or sometimes even calling other programs to tell them not to include the student.

The second tragedy is the student who plays it safe, presuming that some day in the future they will have the position, stature, or whatever to present their doubts about Darwin. Many people counsel this procedure – keep your head low, and don’t say anything until you have tenure. The problem with this course, however, is that we do what we practice. It takes 10 years of schooling at least to get all the way through. If you have spent ten years practicing cowering in the corner, that is exactly what you will do when the time comes for you to speak out. You will not come out as Zorro prancing from the shadows with you blade. You will instead do what you have always done – find one more thing that you have to do first.

“I have to graduate.”
“I have to finish my postdoc.”
“I have to get tenure.”
“I’m working on a grant for a big project.”
“I’ll come out when I retire.”

I don’t mean to offend – I realize just how high the stakes are – but I don’t know of any other way to say this. When you follow this path, what you’ve done is practice being a coward. So, when the epic moment comes for you to say the right thing, do the right thing, or even help out some other person who believes the same way you do, you will instead do exactly what you’ve practiced doing for ten years – run and hide. Even if you did manage a Zorro moment – what use is it? Your colleagues will feel betrayed, and rightly so. They will feel (rightly so) that you’ve been lying to them the whole time – because you have. People will criticize you because your new work, rather than building on your old work to this time, seems to have a sudden break with it – and they would be right.

So what is one to do? Well, thankfully, our friends the evolutionists have given us a way out. In their zeal to claim consensus on the “fact of evolution,” they have had to steamroll together such a large diversity of opinion into the single term “evolution”, that the word “evolution” no longer has the grand meaning it used to. The only real meaning everyone can agree on is “change in allele frequency over time” – and that is a definition that literally everyone can agree with.

In other words, even if you are a young earth creationist, if your professor asks if you believe in evolution, the legitimate answer is “yes”. Given the common definition of “evolution,” the only thing they are really asking with that question is, “do you believe in genetics?”

Therefore, here is how you can, and, I say, should frame yourself – you believe in evolution. However, there are a few parts of the theory that you disagree with. Don’t be obnoxious, but don’t be overly shy either. Just be frank. Do you believe in evolution? “Yes, but I disagree that common ancestry is universal.” Do you believe in evolution? “Yes, but I don’t think that natural selection alone as a mechanism sufficiently explains life’s diversity.” You don’t even have to put the “yes” and the objection in the same sentence. What do you think about evolution? “The study of evolution is fascinating!” How do you think multicellularity evolved? “I think that multicellularity is a fundamental property of certain organisms, and can’t be evolved piecemeal from the presumed single-celled ancestors.” But you do believe in evolution? “Yes, of course.” Do you think multi-cellular organisms evolved? “Certainly!” From what? “Other multi-cellular organisms.”

If someone challenges you on the definition of evolution, simply challenge them back. What definition of evolution are you using? “I’m using the standard population genetics definition of evolution as the change in gene frequencies over time.” That’s not what evolution is. “What is your definition of evolution?” Evolution means natural selection and common ancestry! “Well, that’s a pretty narrow view of evolution in modern biology. So, while I agree with evolution in general, I don’t agree with your specific view of it.” What’s your specific view? “I’m still learning! But I do find it interesting that….[put your favorite evolutionary or non-evolutionary feature of biology here]”

As you can see, if you are well-studied enough, you can state your mind honestly without tying your own noose. Will this work every time? Obviously not. There are in fact people whose inner, personal hostility is beyond any reason. But you will probably run into those people anyway, and better to meet them openly than have them against you behind your back.

Now, in addition to all this, you must remember that, especially when you are in school, you are there to be the student, not the teacher. It is good as a student to learn – and there is much you can learn from people even though they are Darwinists. Some of them have been doing biology for longer than you’ve been alive, and they deserve your respect and attention for that. And so do their ideas. Spend most of your time listening and learning, but don’t be afraid to speak your mind when it is appropriate. Just remember that when you do, speak it wisely. And, given the modern definition of evolution, there is no reason to paint yourself as being an “anti-evolutionist”.

Uncommon Descent

So what happened when that kiddie surgeon Ben Carson gave the speech at Emory graduation?

May 17, 2012

Here (Evolution News & Views, May 16, 2012 )

In the end, President Wagner introduced Dr. Carson gracefully. Carson gave a beautiful speech (no notes or text either), funny and inspiring and eloquent. I got choked up when he talked about Francis Scott Key composing the words that became the lyrics of the “Star Spangled Banner” as he observed the British bombardment of Fort McHenry in 1814. Key saw how the American troops, defending Baltimore Harbor, would not let the flag fall despite being showered by upwards of 1500 cannonballs along with rockets and mortar shells, a lesson in persistence. But I’m not doing justice to the way he tells it. Watch for yourself.

Yes, he addressed the evolution flap and gently but firmly put his critics in their place:

I know there was some controversy about my views on creation and somebody thought that I said that evolutionists are not ethical people. Of course I would never say such a thing and would never believe such a thing nor would anybody with any common sense. So that’s pretty ridiculous.

How could the four professors who drew up the petition of complaint seriously think he meant to say Darwin believers are morally defective, as opposed to acknowledging what’s obviously true — that Darwinian evolution undercuts any coherent defense of moral principles?

Better still, later in the speech and without referencing the Emory dustup, he made an unapologetic pitch for reasoned debate over enforced dogma. “Political correctness,” he said, “threatens the prosperity and the vitality of our nation.”

But the critical thing to see is that it does NOT threaten the Darwinbots who batten off US taxpayers, claiming to know the history of life when they don’t.

Realize: Kid surgeon Ben Carson may be the last guy to ever give a speech at that U who doesn’t conform to their stupid political correctness. No matter useful he might be to you and yours.

While we are here: UD News, whatever you may imagine it is worth (or isn’t) to you, is written by someone who survived a kiddie op in a frontier outpost in Canada in 1958. Seeing the doctor’s terrified face, while going under, … that doc hadn’t done any operations before and, well, he wasn’t Ben Carson, but … hey, Ben would have cheered him on.

The alternative was, kid dies tonight. So the kid’s parents were told. And would never have signed for it otherwise

The kid was unsteady for some weeks, but discovered that feet still exist.

Look, finally, reality must triumph over useless Darwinism, coddling faculty tea parties.

Uncommon Descent

The physicist and the princess

May 16, 2012

Physicist Sean Carroll, an outspoken but ever-courteous defender of the New Atheism, has recently written a post entitled, The Case for Naturalism, at the end of which he kindly encloses a 10-minute video summary of the reasons which have led most scientists to reject the supernatural and accept that the natural world is all there is. The video, which is well worth watching, is excerpted from a two-hour debate held at Caltech on 27 March 2012, on the topic, Has Science Refuted Religion?. Sean Carroll and Michael Shermer argued for the affirmative, while Dinesh D’Souza and Ian Hutchinson argued for the negative.

In the course of his video presentation, Professor Carroll makes reference to a most remarkable woman from the seventeenth century: Princess Elisabeth of Bohemia (1618-1680), who corresponded with the philosopher Rene Descartes on various philosophical matters. Princess Elisabeth was a very learned woman who spoke six languages, was talented at mathematics and was also a gifted painter.

What, you might wonder, does a 17th century princess have to do with the case for naturalism? As Sean Carroll explains in his video, Princess Elisabeth‘s gentle probing of Descartes’ dualism exposed a key weakness in his philosophy – namely, that he was unable to explain how the mind and body interact:

“It’s very natural, very commonsensical to think that a living person possesses something that a corpse does not – some sort of spirit, some sort of animating soul of life force, But this idea, as it turns out, does not stand up to closer scrutiny. And a big step towards realizing this was made back in the 1600s by a remarkable woman named Princess Elisabeth of Bohemia. They named princesses differently back in the 17th century! Elisabeth carried on a years-long correspondence with Rene Descartes who famously tried to develop a theory of mind-body dualism. And Elisabeth said, “I don’t understand what you’re saying, because if you really believe that the mind is in a separate realm from the body, my mind makes a choice to lift my arm, but it’s my body that does it. How does the immaterial mind, which as you say doesn’t exist at a location in space, how does it act causally on the body? How does it interact with the stuff out of which you were made?” And Descartes never came up with a reliable, believable response to this objection. Of course these days the objection is enormously stronger. We’d say: “You are made of atoms. You’re made of cells which are made of molecules which are made of atoms, and as physicists, we know how atoms behave. The laws of physics governing the behavior of atoms are completely understood. You put an atom in a certain set of circumstances, and you tell me what those circumstances are, as a physicist I will tell you what those atoms will do. If you believe that the atoms which are inside your body act differently than they would if they were inside a rock or a crystal, then what you’re saying is that the laws of physics are wrong, that they need to be altered because of the influence of a spirit or soul. That may be true, science can’t disprove that, but there is no evidence for it.”

Professor Carroll’s historical narrative is correct so far as it goes, but there is a lot that he leaves out. To begin with, Princess Elisabeth wasn’t a religious skeptic. Professor Carroll never says she was, of course, but a casual viewer of his video might walk away with that impression. In fact, Princess Elisabeth was a devout Protestant, who (in 1667) became abbess of a Lutheran Abbey at Herford, Saxony, where (according to her Wikipedia biography ) “she distinguished herself by faithfulness in the performance of her duties, by her modesty and philanthropy, and especially by her kind hospitality to all who were oppressed for the sake of conscience.” For his part, Rene Descartes was a Catholic, whose philosophical views were highly unconventional for his day, but whose deep religious faith prompted the Lutheran Queen Christina of Sweden to renounce her throne in order to convert to the religion of her personal tutor, after Descartes’ death in 1650.

The key point here is that in their philosophical correspondence, both Princess Elisabeth and the philosopher Rene Descartes shared a firm belief in the reality of the soul, which Professor Carroll derides as an idea which “does not stand up to closer scrutiny.” What, then, was the source of their disagreement?

Philosopher Deborah Tollefsen addresses this question in an article in Hypatia (14.3, 1999, pp. 59-77), entitled, Princess Elisabeth and the Problem of Mind-Body Interaction. As Tollefsen explains, the disagreement between Princess Elisabeth and Descartes boiled down to the fact that Descartes was a very radical, thoroughgoing dualist who defined the soul in terms of a single property – thought – while defining bodies in terms of another fundamental property: extension. As Princess Elisabeth sensibly pointed out, the total disparity in the properties of the body and the soul makes it impossible to conceive of how the two might interact. (Other critics of Descartes’ had also highlighted this glaring weakness in his radical version of dualism, as Tollefsen mentions in her article.) So what was Princess Elisabeth’s solution? She suggested that in addition to the property of thought, the soul might also have spatial properties, making it physically extended in some fashion. As she put it in a letter to Descartes:

I too find that the senses show me that the soul moves the body; but they fail to teach me (any more than the understanding and the imagination) the manner in which she does it. And, in regard to that, I think there are unknown properties in the soul that might suffice to reverse what your metaphysical meditations, with such good reasons, persuaded me concerning her inextension. And this doubt seems founded upon the rule you lay down there in speaking of the true and the false–namely, that all our errors occur from forming judgements about what we do not sufficiently perceive. Although extension is not necessary to thought, yet not being contradictory to it, it will be able to belong to some other function of the soul (no) less essential to her.
(Blom, John. 1978. Descartes, his moral philosophy and psychology. New York: New York University Press, p. 117; Descartes 1972. Oeuvres de Descartes. Vol. 4. Ed. Charles Adams and Paul Tannery. Paris: Librarie Philosophique J. VRIN, 4:2.)

Tollefsen helpfully elucidates the Princess’s thinking on this issue:

Elisabeth is unhappy with Descartes’s definition of the soul; she pushes him to consider its other attributes because she is convinced that to explain the interaction between mind and body the soul must have an extended element…

Recall that in Elisabeth’s first letter to Descartes she asks him to consider the other attributes of the soul. Here she has returned to this idea. There may be an attribute of the soul, no less essential, which is extended and this extension explains how the soul can move the body and how the body can move the soul. Descartes does not respond to this suggestion. Given his view that the soul has only one essential attribute, he probably found Elisabeth’s suggestion unacceptable. The correspondence shifts at this point from the topic of mind-body interaction to Elisabeth’s health and from there to discussions of moral goodness, the passions, and free will. No mention of Elisabeth’s suggestion occurs in the rest of the correspondence. Although the suggestion that the soul is extended is not one which Descartes’s metaphysics could embrace, it should be noted that this was a common view at the time. (pp. 73, 72.)

The Achilles’ heel of Descartes’ radical version of dualism was he defined soul and body in such a way as to make them so disparate in their properties that they could never conceivably interact. Why, then, does Professor Carroll overlook alternative versions of dualism which are far more sensible, and not vulnerable to the same difficulties? At this point, Carroll might reply that Descartes, for all his faults, was at least perfectly clear about what he was proposing, while Princess Elisabeth’s proposed alternative is somewhat vague. It is no use saying that the soul has spatial properties unless you tie them in with its other properties, in a coherent fashion. Besides, the notion of an immaterial thing having spatial properties sounds very mysterious.

Another solution: hylemorphic dualism

It would have been helpful if Professor Carroll had examined a far older dualistic philosophy that claimed to be able to explain the interaction of soul and body in a smooth, seamless fashion: hylemorphic dualism, which was also espoused by Aquinas and other medieval Scholastic philosophers. Unfortunately, in the 17th century, it had fallen out of vogue in many quarters, but it still has its doughty defenders, to this day. One of the most lucid and articulate of these is Edward Feser, Assistant Professor of Philosophy at Pasadena City College, California. It so happens that Professor Feser has addressed the very problem that plagued Descartes in a blog post entitled, The interaction problem. As Feser sees it, the key problem with Descartes’ dualism was that he conceived of the union of soul and body in purely mechanical terms:

Aristotle and the Scholastic tradition influenced by him famously held that to understand a thing required knowing each of its four causes: its material cause, the stuff out of which it is made; its formal cause, the specific form or essence that stuff has taken on, and which makes it the kind of thing it is; its efficient cause, that which brought it into existence; and its final cause, the end or purpose toward which it is directed. Modern thought is largely defined by its rejection of two of Aristotle’s four causes. For the moderns, there are no such things as substantial forms or fixed essences, and there are no ends or purposes in nature. There are just brute material elements related by purposeless, meaningless, mechanical chains of cause and effect.

As I have emphasized in my series of posts on dualism, this “mechanical” conception of nature, insofar as it stripped matter of anything smacking of either goal-directedness or sensible qualities as common sense understands them, and relocated these features into the mind, more or less automatically entailed a Cartesian form of dualism on which intentionality and qualia are immaterial as a matter of conceptual necessity. But it also automatically entailed that this form of dualism would suffer from the notorious “interaction problem.”

One problem with Descartes’ version of dualism, then, is that he was working with an emaciated concept of matter. Matter, as he envisaged it, had no built-in dispositions or tendencies: its essence consisted in the simple property of extension. Causal interactions between material objects were regarded in mechanical terms. In Feser’s words:

For the moderns, all causation gets reduced to what the Aristotelians called efficient causation; that is to say, for A to have a causal influence on B is for A either to bring B into being or at least in some way to bring into existence some modification of B. Final causality is ruled out; hence there is no place in modern thought for the idea that B might play an explanatory role relative to A insofar as generating B is the end or goal toward which A is directed.

The notion of form, which was so central to Scholastic philosophy, was also shunted to one side:

Formal causality is also ruled out; there is no question for the moderns of a material object’s being (partially) explained by reference to the substantial form it instantiates. We are supposed instead to make reference only to patterns of efficient causal relations holding between basic material elements (atoms, or corpuscles, or quarks, or whatever).

Thus, if the mind considered as immaterial is to have any explanatory role with respect to bodily behavior, this can only be by way of some pattern of efficient causal relations – to put it crudely, in terms of a Cartesian immaterial substance (or perhaps various immaterial properties) “banging” into the material substance (or material properties) of the brain like the proverbial billiard ball. How exactly this is supposed to work is notoriously difficult to explain.

How, then, does hylemorphic dualism solve the interaction? Professor Feser argues that the interaction problem disappears when we treat the soul as the form of the body and not as a separate thing. On this model, the problem of how the soul can interact with the body simply never arises:

But from an Aristotelian-Scholastic point of view, this whole [Cartesian] picture of the mind-body relationship is hopelessly wrongheaded from start to finish. It is wrong to think of the soul (of which the intellect is for Aristotelians but a part, not the whole) and the body as independent objects in the first place. The soul is rather a form that informs the matter of the body and the body is the matter which is informed. As with the form and matter of a stone, tree, or earthworm, what we have here are not two substances interacting via efficient causation, but rather two metaphysical components of one substance related by formal causation. As the form of the stone is to the matter making up the stone, the form of the tree to the matter making up the tree, and the form of the earthworm to the matter that makes up the earthworm, so too is the human soul to the human body. There is in principle no such thing as the matter of a stone, tree, or earthworm apart from the form of a stone, tree, or earthworm respectively, and no such thing as the form of any of these things existing apart from their matter. The form and matter don’t “interact” as if they were two distinct objects; rather, the form constitutes the matter as the (one) kind of object it is in the first place.

My soul, then, is what makes my body a human body, and not the body of a chimp or some other organism, or a pile of dust. Feser contends that whenever I act, my actions have a final cause (the end I’m trying to achieve), a formal cause (the pattern or structure of the action itself), a material cause (the matter in my body that actually carries out the action) and an efficient cause (whatever it is that makes my body move when I act). Feser contends that when I perform a bodily action such as writing a blog, the movement of neurons in my brain and arm and the attendant flexing of muscles constitute the material cause of my action, and also the efficient cause, presumably because these neurons are the parts of my body whose movements cause my hands to move when I press the keys on my computer. My thoughts and intentions, on the other hand, comprise the formal cause and the final cause of my action: my thoughts give the blog post the “form” or structure that it has as an essay, while my intentions define my purpose for writing the post. In Feser’s own words:

As I move my fingers across the keyboard, then, what is occurring is not the transfer of energy (or whatever) from some Cartesian immaterial substance to a material one (my brain), which sets up a series of neural events that are from that point on “on their own” as it were, with no further action required of the soul. There is just one substance, namely me, though a substance the understanding of which requires taking note of each of its formal-, material-, final- and efficient-causal aspects. To be sure, my action counts as writing a blog post rather than (say) undergoing a muscular spasm in part because of the specific pattern of neural events, muscular contractions, and so forth underlying it. But only in part. Yet that does not mean that there is an entirely separate set of events occurring in a separate substance that somehow influences, from outside as it were, the goings on in the body. Rather, the neuromuscular processes are by themselves only the material-cum-efficient causal aspect of a single event of which my thoughts and intentions are the formal-cum-final causal aspect.

Here, then, we have a version of dualism which claims to be immune to the problems that beset Descartes. It is this older version of dualism that was propounded by the medieval Church, and that continued to be promulgated (albeit in a somewhat watered-down form) by many Christian philosophers, even in the 17th century. Professor Carroll’s picture of religion as retreating before the relentless march of scientific naturalism is simply at odds with the facts. It is a great pity that he never attempted to critique this version of dualism in his opening statement at the “Great Debate” held at Caltech on March 27, 2012.

Problem solved? Not quite

It would be tempting at this point to declare the case closed. But an outstanding problem remains. The problem, as I see it, is that Professor Feser does not address the question: what is the efficient cause of the movement of neurons in my brain, when I am writing a blog? What makes these neurons move? What pushes them? An obvious answer would be “the soul,” but Feser expressly rules this out:

The soul doesn’t “interact” with the body considered as an independently existing object, but rather constitutes the matter of the human body as a human body in the first place, as its formal (as opposed to efficient) cause.

There are two comments that I would like to make here. The first is that Feser’s remarks address only a crude Cartesian form of dualism, according to which the soul is the efficient cause of movement in the body (which is ontologically distinct from it). However, they overlook the possibility that the soul, which is the form of the body, is also able to act independently of the body’s matter, and cause certain parts of the body (e.g. neurons in the brain) to move. Here, the soul would be acting as an efficient cause as well as a formal cause.

Second, Feser’s solution to the interaction problem ignores the question of whether the cause of the movement of neurons in my brain is a deterministic cause or not. For instance, if outside stimuli impinging on my body cause the neurons in my brain to move, then it seems there is no room for human freedom, as the action of these stimuli can be described in a deterministic fashion on a molecular level. Throwing in a bit of indeterminism at the subatomic level doesn’t seem to help matters, either; it just creates an element of randomness, which is not the same thing as freedom.

So how is libertarian freedom possible? The answer, I believe, lies in the notion of in top-down causation. To see how this might work, suppose that my brain performs the high-level act of making a choice, and that this act imposes a constraint on the quantum micro-states of tiny particles in my brain. This doesn’t violate quantum randomness, because a selection can be non-random at the macro level, but random at the micro level. The following two rows of digits will serve to illustrate my point.

1 0 0 0 1 1 1 1 0 0 0 1 0 1 0 0 1 1
0 0 1 0 0 0 0 1 1 0 1 1 0 1 1 1 0 1

The above two rows of digits were created by a random number generator. The digits in some of these columns add up to 0; some add up to 1; and some add up to 2.

Now suppose that I impose the non-random macro requirement: keep the columns whose sum equals 1, and discard the rest. I now have:

1 0 1 1 1 0 0 0 0 0 1
0 1 0 0 0 1 1 0 1 1 0

Each row is still random (at the micro level), but I have now imposed a non-random macro-level constraint on the system as a whole (at the macro level). That, I would suggest, is what happens when I make a choice.

Top-down causation and free will

What I am proposing, in brief, is that top-down (macro->micro) causation is real and fundamental (i.e. irreducible to lower-level acts). For if causation is always bottom-up (micro->macro) and never top-down, or alternatively, if top-down causation is real, but only happens because it has already been determined by some preceding occurrence of bottom-up causation, then our actions are simply the product of our body chemistry – in which case they are not free, since they are determined by external circumstances which lie beyond our control. But if top-down causation is real and fundamental, then a person’s free choices, which are macroscopic events that occur in the brain at the highest level, can constrain events in the brain occurring at a lower, sub-microscopic level, and these constraints then can give rise to neuro-muscular movements, which occur in accordance with that person’s will. (For instance, in the case I discussed above, relating to rows of ones and zeroes, the requirement that the columns must add up to 1 might result in to the neuro-muscular act of raising my left arm, while the requirement that they add up to 2 might result in to the act of raising my right arm.)

Thus we can mount a good defense of human freedom by hypothesizing that human choices (which are holistic acts that are properly ascribed to persons) are capable of influencing lower-level events in the human body, such as activities taking place in nerve cells when they process incoming signals. Additionally, we may hypothesize that the operation of nerve cells is not always deterministic, or even deterministic most of the time with occasional random disturbances, but that fundamental, higher-level actions occurring in the brain (i.e. human choices) can constrain the microscopic behavior of nerve cells, and that these constraints, when aggregated over a large number of nerve cells, can result in neuro-muscular movements.

It seems to me, then, that in order to restore human freedom, we have to affirm at least two things: we have to say that people can influence their brains, and we have to say that top-down (macro->micro) causation is real and fundamental. For if causation is always bottom-up (micro->macro) and never top-down, or alternatively, if top-down causation is real, but only happens because it has already been determined by some preceding occurrence of bottom-up causation, then our actions are simply the product of our body chemistry – in which case they are not free, as they are determined by external circumstances which lie beyond our control. But if top-down causation is real and fundamental, then events occurring at a holistic level – including a person’s choices – can determine events at a microscopic level, such as their neuro-muscular movements.

The position we have now reached, then, is that if we want to defend human freedom, we have to believe that human acts (i.e. actions which are properly ascribed to persons and not to their body parts) can and do influence lower-level actions, which occur at various locations in the human body, such as activities taking place in human cells when they process incoming signals. We also have to say that the operation of cells is not always deterministic, or even generally deterministic with occasional random disturbances, but that fundamental, higher-level actions can shape the behavior of cells.

What might these higher-level actions be? It might seem tempting to say that higher-level bodily actions can bring about lower-level bodily actions. That’s fine, so far as it goes. However, if we are to have genuine freedom, then these higher-level bodily actions must be just as ontologically fundamental as the lower-level bodily actions that they determine. For if these higher-level actions are determined by lower-level bodily actions occurring at a previous time, then we are back at square one again: we are once more the prisoners of our body chemistry, and bottom-up causation rules.

Freedom and Immateriality

Could a bodily action, even a higher-level one, be free? I would argue that it cannot, for several reasons. I’ll mention just two; Professor Feser has provided many more (see here, here, here, here and here). First, free choices presuppose a capacity for abstract thinking; but a process taking place at a particular point (or set of points) in my body is (by definition) not abstract but concrete; hence a bodily action is incapable of embodying an abstract concept. Second, free choices and the thoughts that accompany them have an inherent meaning, but bodily processes such as neuronal firings are not inherently meaningful; hence a bodily action is incapable of embodying a free choice. I have discussed these arguments elsewhere, so I won’t elaborate on them here.

The position we have now reached is that if we are to defend human freedom, we have to make a third affirmation; we have to affirm that some human actions (thoughts and choices) are non-bodily actions, and that by performing these actions, human beings are capable of influencing events occurring in the cells of their bodies. And since motor movements begin in the brain, we seem to be committed to the proposition that human beings can, by thinking and choosing, influence events in their brains.

This may sound odd. After all, not everyone knows that they even have a brain: many children don’t, and I imagine many people in times past didn’t know, either. How, it might be asked, can I possibly influence my brain simply by deciding to raise my arm, if I am not thinking about my brain as such, or if I don’t even know I have a brain?

My answer is that we just have to take it as a basic fact of human nature that whenever I perform the non-bodily action of deciding to move my right arm, region “X” of the motor homunculus in my brain (i.e. the area in my brain which governs right arm movements) is activated, and whenever I decide to move my right leg instead, region “Y” of the motor homunculus in my brain (which governs right leg movements) is activated. “How convenient!” you might say. And it is. Indeed, it’s more than convenient – it’s absolutely extraordinary. If we were not made that way, voluntary action would be impossible. Since the soul is the form of the body only, I cannot will other objects to move; telekinesis is impossible. I can only move my body parts.

So my solution to the interaction problem is simply to say that God has made human beings with certain built-in psycho-physical correspondences between their (immaterial) mental acts of choosing to move different body parts, and the resulting movements of the various regions of the brain which govern these different body parts.

I am of course well aware that the foregoing account of the mechanics of voluntary movement is grossly oversimplified, as it overlooks such things as feedback, forward modeling, fine motor-tuning and proprioception. Many of these features are found even in insects, which are responsive to stimuli and capable of associative learning, but lack sentience. Now if people can voluntarily fine-tune their actions, then of course they need to be aware at a conscious level of what’s happening to their bodies when they move. However, I don’t think that we need to postulate any extra psycho-physical correspondences on that account. At the very most, we might need further correspondences between people’s mental acts of choosing and other parts of their nervous system, besides the motor homunculus in the brain.

I would like to conclude by saying that the problem of the relation between mind and body is a difficult one, no matter what your philosophical perspective. A modified version of hylemorphic dualism remains philosophically tenable and compatible with the scientific facts. Descartes’ dualism is a straw man. As for materialism, it’s an option that I would describe as “not even wrong,” as it fails to address the simple question of how our thoughts come to have a meaning – which they cannot do if they are simply neural processes.

Uncommon Descent

Has biology suddenly discovered ecology?

May 16, 2012

Not as long as Darwin reigns. Darwin’s trolls can work big magic.

From “Mixed Bacterial Communities Evolve to Share Resources, Not Compete” (ScienceDaily, May 15, 2012), we learn

Predicting how species and ecosystems will respond to new environments is an important task for biology. However, most studies of evolutionary adaptation have considered single species in isolation, despite the fact that all species live in diverse communities alongside many other species. Recent theories have suggested that interactions between species might have a profound effect on how each species evolves, but there has been little experimental support for these ideas.

There would be way more if Darwinism wasn’t the local profbot’s iron rice bowl. Anyway this:

The research team, from Imperial College London, found that bacteria that evolved in a mixed community with other species altered their feeding habits to share resources more effectively amongst themselves and to make use of each other’s waste products in a cooperative manner. In contrast, when grown alone, the same species evolved to use the same resources as each other, thereby competing and impairing each other’s growth.

Uncommon Descent