Edward Feser's Blog, page 83

Anscombe Society event

On April 11, I’ll be giving the Princeton Anscombe Society 10th Anniversary Lecture, on the subject “Natural Law and the Foundations of Sexual Ethics.”  Prof. Robert George will be the moderator.  Details here.

Capital punishment should not end (UPDATED)

Four prominent Catholic publications from across the theological spectrum -- Americamagazine, the National Catholic Register, the National Catholic Reporter and Our Sunday Visitor -- this week issued a joint statement declaring that “capital punishment must end.”  One might suppose from the statement that all faithful Catholics agree.  But that is not the case.  As then-Cardinal Ratzinger famously affirmed in 2004, a Catholic may be “at odds with the Holy Father” on the subject of capital punishment and “there may be a legitimate diversity of opinion even among Catholics about… applying the death penalty.”  Catholic theologian Steven A. Long has issued a vigorous response to the joint statement at the blog Thomistica.net.  (See also Steve’s recent response to an essay by “new natural law” theorist and capital punishment opponent Christopher Tollefsen on whether God ever intends a human being’s death.) 
Apart from registering my own profound disagreement with the joint statement, I will for the moment refrain from commenting on the issue, because I will before long be commenting on it at length.  My friend Joseph Bessette is a professor of government at Claremont McKenna College.  Joe and I have for some time been working together on a book on Catholicism and capital punishment, and we will complete it soon.  It will be, to our knowledge, the most detailed and systematic philosophical, theological, and social scientific defense of capital punishment yet written from a Catholic perspective, and it will provide a thorough critique of the standard Catholic arguments against capital punishment.More on that before long.  In the meantime, interested readers are directed to my previous writings on capital punishment.  In 2005, at the old Right Reason group blog, I engaged in an exchange with Tollefsen on the subject of capital punishment, natural law, and Catholicism.  My contribution to the exchange can be found here:

Catholicism, conservatism, and capital punishment
In a 2011 post I commented on the failure of some churchmen to present the entirety of Catholic teaching on the subject of capital punishment, and their resulting tendency to convey thereby the false impression that the Church’s attitude on this issue is “liberal”:
Deadly unserious
In 2011 I also engaged in a longer exchange with Tollefsen on the subject of capital punishment, both at Public Discourseand here at the blog.  My side of the debate can be found at the following links:
In Defense of Capital Punishment
On rehabilitation and execution
Punishment, Proportionality, and the Death Penalty: A Reply to Chris Tollefsen
Tollefsen channels Rawls
Finally, in a 2012 post I addressed some common confusions about retributive justice and its relationship to revenge:
Justice or revenge?
Joe Bessette is also currently completing his own, separate book on capital punishment: Murder Most Foul: a Study and Defense of the Death Penalty in the United States.  Some of his previous writings on capital punishment and criminal justice more generally are linked here:
Why the Death Penalty is Fair (with Walter Berns)
Shameless Injustice
In Pursuit of Criminal Justice

UPDATE 3/10: Canon lawyer Edward Peters, Carl Olson at Catholic World Report, and Matt Briggs have now also responded to the joint statement.

Capital punishment should not end

Four prominent Catholic publications from across the theological spectrum -- Americamagazine, the National Catholic Register, the National Catholic Reporter and Our Sunday Visitor -- this week issued a joint statement declaring that “capital punishment must end.”  One might suppose from the statement that all faithful Catholics agree.  But that is not the case.  As then-Cardinal Ratzinger famously affirmed in 2004, a Catholic may be “at odds with the Holy Father” on the subject of capital punishment and “there may be a legitimate diversity of opinion even among Catholics about… applying the death penalty.”  Catholic theologian Steven A. Long has issued a vigorous response to the joint statement at the blog Thomistica.net.  (See also Steve’s recent response to an essay by “new natural law” theorist and capital punishment opponent Christopher Tollefsen on whether God ever intends a human being’s death.) 
Apart from registering my own profound disagreement with the joint statement, I will for the moment refrain from commenting on the issue, because I will before long be commenting on it at length.  My friend Joseph Bessette is a professor of government at Claremont McKenna College.  Joe and I have for some time been working together on a book on Catholicism and capital punishment, and we will complete it soon.  It will be, to our knowledge, the most detailed and systematic philosophical, theological, and social scientific defense of capital punishment yet written from a Catholic perspective, and it will provide a thorough critique of the standard Catholic arguments against capital punishment.More on that before long.  In the meantime, interested readers are directed to my previous writings on capital punishment.  In 2005, at the old Right Reason group blog, I engaged in an exchange with Tollefsen on the subject of capital punishment, natural law, and Catholicism.  My contribution to the exchange can be found here:

Catholicism, conservatism, and capital punishment
In a 2011 post I commented on the failure of some churchmen to present the entirety of Catholic teaching on the subject of capital punishment, and their resulting tendency to convey thereby the false impression that the Church’s attitude on this issue is “liberal”:
Deadly unserious
In 2011 I also engaged in a longer exchange with Tollefsen on the subject of capital punishment, both at Public Discourseand here at the blog.  My side of the debate can be found at the following links:
In Defense of Capital Punishment
On rehabilitation and execution
Punishment, Proportionality, and the Death Penalty: A Reply to Chris Tollefsen
Tollefsen channels Rawls
Finally, in a 2012 post I addressed some common confusions about retributive justice and its relationship to revenge:
Justice or revenge?
Joe Bessette is also currently completing his own, separate book on capital punishment: Murder Most Foul: a Study and Defense of the Death Penalty in the United States.  Some of his previous writings on capital punishment and criminal justice more generally are linked here:
Why the Death Penalty is Fair (with Walter Berns)
Shameless Injustice
In Pursuit of Criminal Justice

William Wallace, OP (1918-2015)

Fr. William A. Wallace has died.  Wallace was a major figure in Aristotelian-Thomistic philosophy of nature and philosophy of science, and the author of many important books and academic articles.  Still in print are his books The Modeling of Nature: Philosophy of Science and Philosophy of Nature in Synthesis (a review of which can be found here), and The Elements of Philosophy: A Compendium for Philosophers and Theologians .  Among his many other works are his two-volume historical study Causality and Scientific Explanation, the classic paper “Newtonian Antinomies Against the Prima Via” which appeared in The Thomist in 1956 (and is, unfortunately, difficult to get hold of if you don’t have access to a good academic library), and a collection of some of his essays titled From a Realist Point of View.  An interview with Wallace can be found here, and curriculum vitae here.  Here is the text of a series of lectures by Wallace on philosophy of nature, and here is a YouTube lecture.  Some of Wallace’s articles are among those linked to here.  RIP.

Nyāya arguments for a First Cause

As I noted in an earlier post, arguments for a divine First Cause can be found in Indian philosophy, particularly within the Nyāya-Vaiśeșika tradition.  They are defended by such thinkers as Jayanta Bhatta (9th century A.D.), Udayana (11th century A.D.), Gangesa (13th century A.D.), and Annambhatta (17th century A.D.).  Translations of the key original texts and some of the most important studies in English are not easy to find, but useful discussions are readily available in books like Kisor Kumar Chakrabarti’s Classical Indian Philosophy of Mind: The Nyāya Dualist Tradition , Ben-Ami Scharfstein, A Comparative History of World Philosophy , and Parimal G. Patil’s Against a Hindu God: Buddhist Philosophy of Religion in India .As with Aristotelian and Leibinizian versions of the cosmological argument, the Nyāya arguments are not arguments for a temporalFirst Cause.  On the contrary, the material universe is regarded as having always existed.  To be sure, the world is thought of as being cyclically created, destroyed, and recreated, but the material substrate underlying it persists throughout.  This substrate is conceived of in atomist terms.  The objects we perceive are wholes composed of parts.  The smallest perceivable parts are called triads, each of which is composed of three dyads, which are imperceptible.  Dyads in turn are each composed of two atoms, which, naturally, are also imperceptible.  The atoms, unlike the composites made out of them, neither come into being nor pass away.  They are the basic furniture of the material universe, indivisible and indestructible.  For the Nyāya atomist, there must be some such level of parts because otherwise things would be infinitely divisible, and thus have an infinite number of parts.  And in that case we would not be able to account for the different sizes of things, since if everything had an infinite number of parts they should all be of the same size.  (Compare Zeno’s paradox of large and small, from which he draws a very different lesson!)  The Nyāya view is also that a material effect is always made out of preexisting matter, so that the fundamental, atomic level of matter is not a kind of effect.

So, what Nyāya arguments for a First Cause purport to explain is neither the beginning of the universe (for it had no beginning) nor the existence of the atoms (for they are regarded, not as a kind of material effect, but rather as the basic preconditions of there being any material effects).  What such arguments purport to explain is rather the most fundamental sort of material effect, the kind that underlies every other, viz. the existence of dyads.  The reasoning is not that if we trace effects backward in time we’ll get to a temporally first effect, such as the Big Bang, and have to ask what caused that.  It is rather that if we trace effects downward here and now we’ll get to a metaphysically most fundamental sort of effect, the existence of dyads, and need to explain that.
Nyāya arguments also deploy a distinctive version of the principle of causality, according to which any effect requires a causal agent that is aware of the material stuff out of which the effect is made, desires to bring that effect about, and wills to do so.  The stock example is that of a pot, whose maker is aware of the clay out of which it is made, desires to make that clay into a pot, specifically, and wills to do so.  Why suppose that every effect has such a cause?  The Nyāya answer is that artifacts (pots, etc.) provide many confirming instances of this general principle, and that atoms are not counterexamples because they are not effects in the first place.  Moreover, though the atheist would claim that composite material things that are not artifacts (stones, etc.) are counterexamples, this charge (so the argument goes) begs the question.  For whether or not such objects are at least in part the effect of a causal agent with awareness, desire, and will -- namely God, as cause of the dyads out of which the objects are composed -- is precisely what is at issue.
No doubt the atheist will balk at this move, but Chakrabarti not implausibly suggests that it is really no different from the sort of move materialists commonly make in response to objections raised by dualists.  To take just one example (mine rather than Chakrabarti’s), if a dualist claims that material phenomena are all directly knowable from the “third-person” point of view whereas mental states are directly knowable only from the “first-person” point of view, the materialist will typically respond that by itself this claim begs the question and is thus no refutation of materialism.  For the materialist might argue that whether mental states really can be directly known only from the “first-person” point of view is precisely part of what is in question.  If the materialist regards this as a legitimate way of disarming a seemingly obvious counterexample to his position, why can’t the Nyāya theist similarly disarm the purported counterexamples atheists would raise against his version of the principle of causality?
With this background in place, I suggest that we might summarize the basic thrust of Nyāya arguments for a First Cause as follows:
1. Dyads are the fundamental sort of effect.
2. Any effect is the product of a causal agent which has awareness, desire, and will.
3. So dyads are the product of a causal agent which has awareness, desire, and will.
But why suppose there is a unique causal agent of this sort, and why attribute the divine attributes to such an agent?  The Nyāya approach to answering such questions might (roughly following Chakrabarti) be summarized as follows.  For the reasons already given, the causal agent in question must have awareness, desire, and will.  But it nevertheless cannot be comparable to a human causal agent.  For one thing, since human beings are composed of dyads, their existence presupposes dyads and thus cannot be the explanation of dyads.  For another thing, being imperceptible, the atoms out of which dyads are composed are not the sort of thing of which human beings can be aware, and a causal agent of the sort the argument posits must be aware of the materials out of which it makes the dyads.  So, the causal agent in question must, unlike human beings, be incorporeal.  Since it exists before the fundamental effect does, it must be without beginning.  If it is without beginning it must also be simple or non-composite, otherwise it would itself have parts and would exist only after those parts are combined.  If it is simple and thus without parts to be broken down into, it must be everlasting.  And considerations of parsimony (what in Western philosophy is called the principle of Ockham’s razor) tell against there being more than one such causal agent. 
Naturally, the Thomist is bound to find the overall project of such arguments congenial.  But he is also bound to take issue with the details.  Even if we were to accept atomism or some variant on atomism -- in the traditional philosophical sense of “atomism,” that is (naturally I do not deny the existence of atoms in the modern sense in which the term is used in physics) -- atoms would, for the Thomist, still have a cause.  For they would be composites of substantial form and prime matter and of essence and existence, and (as the Nyāya argument itself emphasizes) what is composite requires a cause.  (See pp. 177-84 of Scholastic Metaphysics for exposition and defense of the Aristotelian-Thomistic critique of atomism.)  Thus, the Nyāya argument is, from a Thomistic point of view, not radical enough in its attempt to trace the world to a divine cause.  Still, we cannot be too hard on it on that account.  That what is composite has a causeis an absolutely crucial insight in natural theology, and it is key to the Nyāya approach.
So, the Thomist would disagree with the claim of premise 1 that dyads are the fundamental sort of effect, but he would certainly agree with the deeper point that whatever the most fundamental composites turn out to be would require an efficient cause.  There are also problems with premise 2.  Here I think the atheist would be right to complain that we can’t draw general conclusions about efficient causality from the example of artifacts, because artifacts are rarer (indeed much rarer) than effects where no cause having awareness, desire, and will is evident.  So, while we are certainly justified in holding that composites, including non-artifacts, must have an efficient cause, getting to a cause that has awareness, desire, and will would require much further argumentation. 
Still, there is something to what the Nyāya approach is saying.  For the Thomist, we must attribute to any causal agent active potencyor power; potencies or powers are always directed toward the generation of a certain effect or range of effects; and what is in an effect is always first in its total efficient cause in some way, whether formally, virtually or eminently -- this last point being the Scholastic “principle of proportionate causality.”  (See chapters 1 and 2 of Scholastic Metaphysics for exposition and defense of the Aristotelian-Thomistic approach to efficient causality.)  These features are arguably analogous to those which the Nyāya premise 2 attributes to efficient causes.  In particular, active potency or power is analogous to “will,” the directedness of a cause toward its effects is analogous to “desire,” and a total efficient cause’s having what is in the effect before the effect is generated is analogous to “awareness.” 
But of course, non-human natural causes do not really have “will,” and non-animal natural causes do not really have “desire” or “awareness.”  For the Thomist, most of the efficient causes operative in the natural order are completely devoid of sentience, intellect and will (even if they ultimately derive their causal power, at every moment at which they operate, from a divine First Cause).  The Nyāya approach, tying efficient causality as it does directly to awareness and will, seems to threaten to lead to occasionalism.

Descartes’ “indivisibility” argument

In the sixth of his Meditations on First Philosophy , Descartes writes:
[T]here is a vast difference between mind and body, in respect that body, from its nature, is always divisible, and that mind is entirely indivisible.  For in truth, when I consider the mind, that is, when I consider myself in so far only as I am a thinking thing, I can distinguish in myself no parts, but I very clearly discern that I am somewhat absolutely one and entire; and although the whole mind seems to be united to the whole body, yet, when a foot, an arm, or any other part is cut off, I am conscious that nothing has been taken from my mind; nor can the faculties of willing, perceiving, conceiving, etc., properly be called its parts, for it is the same mind that is exercised [all entire] in willing, in perceiving, and in conceiving, etc.  But quite the opposite holds in corporeal or extended things; for I cannot imagine any one of them [how small soever it may be], which I cannot easily sunder in thought, and which, therefore, I do not know to be divisible.  This would be sufficient to teach me that the mind or soul of man is entirely different from the body, if I had not already been apprised of it on other grounds.This is Descartes’ “indivisibility argument” for dualism.  As with many of Descartes’ other arguments, I think both that it is not compelling as it stands, but also that it is much more interesting than it is often given credit for.  I devoted a few pages to the argument in Philosophy of Mind .  I won’t repeat here everything I said there. 

As Dale Jacquette interprets Descartes in his own book Philosophy of Mind , the argument can be summarized as follows:
1. My body is divisible into like parts (bodies)
2. My mind is not divisible into like parts (minds)
3. My body ≠ my mind
Jacquette’s reason for speaking of divisibility “into like parts” is that Descartes does not deny that we can distinguish different faculties within the mind, such as willing, perceiving, and conceiving.  What Descartes denies (on Jacquette’s reading) is that the mind can be divided into parts which are themselves minds.  The idea would be that you cannot divide a mind into parts that are like what you started out with (two or more minds), whereas you can divide a material object into parts that are like what you started out with (two or more material objects).  So, material things have a property that minds lack, viz. divisibility into like parts.  And thus, by Leibniz’s Law, the mind cannot be identified with a material thing.
Suppose we accept Jacquette’s reading.  What should we think of the argument?  It might seem at first glance that the argument fails with the first premise.  For isn’t it simply false to say of material things in general that they are divisible into like parts?  To be sure, if you divide a stone in half, you get two stones, and if you divide a piece of wood you get two pieces of wood.  But if you divide a human body in half, you do not get two human bodies; if you divide a car, you don’t get two cars; if you divide a circular object, you don’t get two circles; and so forth.  Indeed, even with stone and wood, if you keep dividing them you’ll eventually get to something that isn’t stone or wood.
But this objection is too quick.  Since Descartes was obviously aware of these facts, he cannot have meant that if you divide a human body you’ll get two human bodies, etc.  So what does he mean?  Recall that for Descartes, the essence of matter is to be extended in space.  Matter just is extension, and nothing but extension.  Thus when he says that body is divisible into like parts, what he means, no doubt, is that if you divide an extended thing the result will be two or more things that are also extended.  They may not be human bodies, specifically, or cars, or what have you, but they will be extended.  So, given Descartes’ conception of matter, it is certainly understandable why he would take the first premise to be true.
We’ll come back to that, but let’s turn for the moment to the second premise.  If for Descartes the essence of matter is extension, the mind is, on his view, essentially that which thinks to itself: I think, therefore I am.  It is the “I,” the ego, the self which remains in Meditation II after everything else has been doubted away by the end of Meditation I.  When Descartes (as Jacquette interprets him) says that the mind cannot be divided into like parts, I would suggest that what he means is that you can’t break an “I” or ego down into two or more “I’s” or egos, the way you can break an extended thing down into two or more extended things.
Why does Descartes think that the self or ego is indivisible in this way?  Note first that Descartes says that “when a foot, an arm, or any other part is cut off, I am conscious that nothing has been taken from my mind.”  He seems to be alluding here to the argument of Meditation I to the effect that it could in principle turn out that none of his “hands, eyes, flesh, blood [and] senses” are real, insofar as his belief that his body exists could be a delusion foisted upon him by an evil spirit.  The point, I take it, is not that his mind might in principle exist even if his body did not; that would be the thrust of his “clear and distinct perception” argument for dualism, and the “indivisibility” argument is presumably supposed to be an independent argument for dualism.  The point in the present context seems rather to be to give an example of something that might at first glance appear to be a part of the self which on reflection is not really part of the self at all.  An arm might seem to be a part of the “I” or ego, yet the “I” or ego can conceive of a situation in which it turns out that the arm does not exist, and perhaps never existed but was always only ever a hallucination, and yet where the “I” or ego nevertheless exists all the same.  Hence the arm isn’t really a part of the “I” or ego, but at best just something contingently attached to it.  And of course, if separated an arm certainly wouldn’t constitute another “I” or self all on its own.
But couldn’t there be a case of a mental (as opposed to bodily) part of the self which, if it were to be lost, would constitute another “I” or self that has split off?  In particular, don’t the phenomena associated with “dissociative identity disorder” and “split brain” patients provide evidence that this can happen?  As I noted in Philosophy of Mind, the significance of such phenomena has been greatly exaggerated.  How to interpret these cases is a matter of controversy, and in my view there is nothing going on in them that amounts to a single mind splitting into two, but merely a single mind becoming severely addled.  But suppose for the sake of argument that in some of these cases there really are two or more utterly distinct minds where previously there seemed to be only one.  Would Descartes have regarded this as a refutation of his thesis?
I think not.  Suppose you found yourself in a situation in which another mind suddenly seemed to be sharing control of your body.  Perhaps it would invade your thoughts and you would consciously struggle with it for control, like Steve Martin does with Lily Tomlin in the movie All of Me .  Or perhaps it would completely take over control for extended periods of time without your realizing what is going on, as in (too-late spoiler alert!) Fight Club .  Either way, I imagine Descartes would argue as follows: You could easily conceive of being rid of this second mind or self and carrying on “one and entire” without it, just as you can conceive of your “I” or ego carrying on “one and entire” in the absence of your arm or foot.  And in that case this other mind or self was never really a part of the “I” or ego at all, any more than the arm or foot was, but only something contingently associated with it.  Even if it seemed that it had “split off” from you, this would be an illusion.  It could only ever have been something contingently attached to you which you had belatedly become aware of, like a barnacle on a ship that has been attached to it for weeks before it is detected and scraped off.  For if this second self had ever really been a part of you, then you could not conceive of continuing “one and entire” without it.  You would instead be conceiving of a case where you persist in a diminished or incomplete way in the absence of this other mind or self.  But in fact what you are conceiving of is continuing in a complete way in the absence of something alien which had for whatever reason come to be attached to you.  A purported second “I” or ego which splits off from my “I” or ego is thus like the body: I can conceive of existing without it, and thus it is not really a part of the original “I” or ego at all.
If this is correct, then Descartes’ argument might seem to go through.  If the “I” or ego were a material (i.e. extended) thing, then since from any material thing you can split off a part that is itself a material thing, it should also be the case that you can split off from the “I” or ego a part that is itself an “I” or ego.  But that is not the case.  So the “I” or ego is not a material thing.
But not so fast.  The argument is still problematic, and, it seems to me, more because of what Descartes says about matter than because of what he says about the “I” or ego.  For one thing, the argument seems to presuppose that matter is infinitelydivisible, that no matter how far down you go in dividing a material thing you will always be able to divide the resulting parts further.  And indeed, that is precisely what Descartes thinks.  But that is, needless to say, a highly controversial assumption.  Suppose a critic opted instead for an atomist account of matter on which there is a bottommost level of material bits which cannot be divided further, or a corpuscularian theory on which there is a bottommost level that might in principle be divided further but in fact is not so divided.  Would that sink Descartes’ argument?
The Cartesian might respond as follows: Even if there is such a level, it would not help the materialist.  For the materialist wants to identify the self with some material object at the macro level -- in particular, with the brain.  And macro level objects like the brain are in the relevant sense divisible into like parts.  Hence the “I” or ego could not be identified with any of them.
The trouble with this reply, though, is that a materialist willing to think outside the box could decide to identify the “I” or self with an atom or corpuscle.  He could say: “I’m happy to think of the ego or self, as Descartes does, as akin to a Leibnizian monad -- as simple, undivided, or non-composite.  But unlike Descartes and Leibniz, I think it should nevertheless be identified with a material thing that is simple, undivided or non-composite.  It’s comparable to what Leibniz would call the ‘dominant monad’ of a system.  It’s the one atom or corpuscle in the human body that is associated with thought, and governs all the other, unthinking atoms or corpuscles that make up the body.” 
Needless to say, this materialist move would itself be problematic in several ways.  Why would some atoms or corpuscles be associated with thought while others are not?  How exactly does this one purportedly thinking material particle govern the rest? How could there be any material thing, however minute, that is in principle indivisible or non-composite?
But to address such questions would be to go well beyond what Descartes has to say in the indivisibility argument itself.  So, because such questions would need to be addressed -- and because I think Descartes’ own conception of matter is just wrong -- I think the “indivisibility” argument as it stands is not compelling.  But that doesn’t mean that there aren’t insights in it that couldn’t be developed into a better argument.  Indeed, we Aristotelian-Thomists would certainly hold that there is a sense in which any material substance can be decomposed into component parts (insofar as even the simplest or bottommost material substances are still going to be composed of substantial form and prime matter).  And Thomists also hold that there is a sense in which the soul is simple or non-composite (though of course it does not have the absolute simplicity that is unique to God). 
But spelling all this out would take us far from anything distinctively Cartesian.  And that is no surprise.  As I have noted in earlier posts (here, here, and here) what is of abiding value in Descartes’ arguments typically turns out to be the elements he borrowed from the Scholastic tradition that preceded him rather than the novelties he introduces.

Braving the web

The 10thAnnual Thomistic Seminar for graduate students in philosophy and related disciplines, sponsored by The Witherspoon Institute, will be held from August 2 - 8, 2015 in Princeton, NJ.  The theme is “Aquinas and Contemporary Ethics,” and faculty include John Haldane, Sarah Broadie, and Candace Vogler.  Applications are due March 16.  More details here.
Does academic freedom still exist at Marquette University?  The case of political science professor John McAdams, as reported by The Atlantic , Crisis magazine , and Slate . 
The late Fr. Richard John Neuhaus is the subject of a new biography by Randy Boyagoda.  Review at National Review , and podcast of an interview with Boyagoda at Ricochet.At Aeon magazine, Philip Ball comments on physics, philosophy, and “half-baked” ideas like the “many worlds interpretation” of quantum mechanics.

If “Bush lied, people died,” then why didn’t the Bush administration play up the WMDs it did find, so as to make the “lie” more plausible?  Don’t ask Jon Stewart.
New books in philosophy of religion: Gaven Kerr’s Aquinas’s Way to God , Paul O’Grady’s Aquinas’s Philosophy of Religion , and Fiona Ellis’s God, Value, and Nature .
Christopher Blum on how Aristotle invented science.
Philosopher Tom V. Morris has written high powered academic philosophy books and many popular works.  He also has a blog.
Philosopher Dennis Bonnette asks: Does Richard Dawkins exist?
But the New Atheism is old hat.  Here’s philosopher Philip Kitcher’s “soft atheism.”
Thomas Ward’s new book John Duns Scotus on Parts, Wholes, and Hylomorphism is reviewed by Robert Pasnau at Notre Dame Philosophical Reviews. 
Asimov’s Foundation is reviewed at Omni Reboot.  Better late than never.

Augustine and Heraclitus on the present moment

On the subject of time and our awareness of it, Augustine says the following in The Confessions:
But how does this future, which does not yet exist, diminish or become consumed?  Or how does the past, which now has no being, grow, unless there are three processes in the mind which in this is the active agent?  For the mind expects and attends and remembers, so that what it expects passes through what has its attention to what it remembers…
Suppose I am about to recite a psalm which I know.  Before I begin, my expectation is directed towards the whole.  But when I have begun, the verses from it which I take into the past become the object of my memory.  The life of this act of mine is stretched two ways, into my memory because of the words I have already said and into my expectation because of those which I am about to say.  But my attention is on what is present: by that the future is transferred to become the past. (Confessions11.28.37-38, Chadwick translation; an older translation is available online here)So, it seems that for Augustine, for conscious awareness to “attend” to the present moment presupposes also both its “remembering” the immediate past and its “expectation” of the immediate future.  For example, when reciting the twenty third Psalm, my present awareness of speaking the words “…my shepherd…” has the significance and phenomenal feel that it does only because I simultaneously remember just having said “The Lord is…” and also simultaneously expect to follow the words I am speaking with “…I shall not want.”  Awareness of the present moment has intentionality in two directions: it “points” or is “directed” backwards toward the moment that preceded it, and forwards toward the moment that will succeed it. 

Augustine makes a similar point elsewhere, when he says that we cannot hear even a single syllable
unless memory helps us so that, at the moment when not the beginning but the end of the syllable sounds, that motion remains in the mind which was produced when the beginning sounded (De musica 6.5.10, quoted in Roland Teske, “Augustine’s Philosophy of Memory” in Stump and Kretzmann, The Cambridge Companion to Augustine, First edition )
This two-directional intentionality appears to be the key to our sense of the unity of the self over time.  Note that I say, not that it is the key to the self’s unity, but that it is the key to our sense of the self’s unity.  As I’ve said elsewhere, I think the self would in fact persist even if its memory of its past were obliterated.  What would be lost in that case is not its identity, but merely its knowledgeof its identity.  The Lockean idea that “who I am” is defined by my memories of the past and plans for the future is bad metaphysics, but it is good epistemology.  Such memories and expectations don’t constitute the self’s identity, but in normal cases (i.e. when one is not suffering from brain damage, mental illness, or the like) they will follow from and manifest its identity.  (They are, to use the Scholastic metaphysical jargon a little loosely, something like “proper accidents” of identity.)  The self’s remembrance of its distant past history and expectation of the carrying out of its long-range future plans is an extension of the memory of the immediate past and expectation of the immediate future of which Augustine speaks.
This two-directional intentionality in the subjective realm of the mind has a parallel in the objective world.  For the Scholastic metaphysician, the natural world is governed by the principle of finality and the principle of proportionate causality.  According to the principle of finality, efficient causes are “directed toward” or “point” forward to their characteristic effects, as toward a final cause.  And according to the principle of proportionate causality, effects “point” backwards, toward their efficient causes.  These principles are, to use Hume’s language (though not his principles), the “cement of the universe” that keeps things and events from being “loose and separate.” 
As I have argued many times, it was the early moderns’ abandonment of immanent final causality -- final causality as an inherent feature (as opposed to an observer-relative feature) of natural phenomena -- that paved the way for Humean skepticism about efficient causality.  As Aquinas argued, if efficient causes were not “pointed” or “directed toward” their characteristic effects, there would be no way to explain why those effects are in fact the ones which characteristically follow.  Things really would objectively be “loose and separate.”  (As usual, see Scholastic Metaphysics for detailed defense of all this Scholastic metaphysics.) 
If “directedness” did not exist even in the mind -- that is to say, if intentionality were an illusion, as eliminative materialism holds -- then the self’s sense of its own unity over time would also be undermined.  Just as the objective world breaks apart into innumerable disconnected distinct existences in the absence of final causality, so too does the subjective world break apart into innumerable disconnected distinct moments of awareness in the absence of intentionality.  Present awareness would not “point” backward to the immediate past or forward to the immediate future.  Its entire content would be limited to the present instant, and there would be no sense of a self that extended beyond that instant.
These implications of Humeanism and eliminativism are, of course, foreshadowed in Heraclitus’s philosophy, at least as traditionally interpreted.  For the Heraclitean, all is flux, and there are no abiding entities.  That includes the self.  There is no “I” that persists over time; there is only an awareness of the present instant followed by an awareness of the next instant followed by an awareness of the next, with no one abiding thing that has all of these awarenesses. 
Now, part of the significance of Augustine’s observation is that it indicates how the Heraclitean account is not true to the phenomenology of the sense of self.  We simply don’t perceiveourselves as existing merely in the present instant, for as Augustine points out, awareness of the present instant also involves in the normal case a remembrance of the past and an expectation of the future.  This two-directional intentionality is built into awareness of the present, and can be absent only when our cognitive faculties are malfunctioning. 
But there is a deeper lesson.  Augustine’s observation also helps us to see why the Heraclitean position cannot really be coherently formulated.  For suppose I try to think the thought that there is no abiding self.  As Augustine would point out, the words “…no abiding…,” as uttered inwardly to oneself, have their significance only insofar as I remember that they were preceded by an utterance of “There is…” and expect that they will be followed by an utterance of “…self.”  Now, these different utterances occur at different times, and are thus the objects of distinct acts of awareness.  But if the Heraclitean position is correct, there is no single abiding self that underlies these acts of awareness.  Thus there would be no one self that could have the thought that there is no abiding self.  The self that begins the thought would not be the same as the self which continues the thought, and neither would be the same as the self that completes the thought.  There would be nothing that actually has that particular thought.  Hence if Heraclitus’s position were correct, no one could so much as formulate it, for no one could last long enough to do so.  And yet we do formulate the position, as is evidenced by the fact that we can entertain it, argue about it, accept or reject it.  The very act of formulating Heraclitus’s position thereby refutes it.
So, Heraclitus was wrong.  How appropriate, then, that in the little montage above, Augustine seems to be hearing Heraclitus’s confession!

Accept no imitations

Given that he’s just become a movie star, Alan Turing’s classic paper “Computing Machinery and Intelligence” seems an apt topic for a blog post.  It is in this paper that Turing sets out his famous “Imitation Game,” which has since come to be known as the Turing Test.  The basic idea is as follows: Suppose a human interrogator converses via a keyboard and monitor with two participants, one a human being and one a machine, each of whom is in a different room.  The interrogator’s job is to figure out which is which.  Could the machine be programmed in such a way that the interrogator could not determine from the conversation which is the human being and which the machine?  Turing proposed this as a useful stand-in for the question “Can machines think?”  And in his view, a “Yes” answer to the former question is as good as a “Yes” answer to the latter.This way of putting things is significant.  Turing doesn’t exactly assert flatly in the paper that machines can think, or that conversational behavior of the sort imagined entails intelligence, though he certainly gives the impression that that is what he believes.  (As Jack Copeland notes in his recent book on Turing (at p. 209), Turing’s various statements on this subject are not entirely consistent.  In some places he explicitly declines to offer any definition of thinking, while at other times he speaks as if studying what machines do can help us to discover what thinking is.)  What Turing says in the paper is that the question “Can machines think?” is “too meaningless to deserve discussion,” that to consider instead whether a machine could pass the Turing Test is to entertain a “more accurate form of the question,” and that if machines develop to the point where they can pass the test, then “the use of words and general educated opinion will have altered so much that one will be able to speak of machines thinking without expecting to be contradicted.”

This is very curious.  Suppose you asked me whether gold and pyrite are the same, and I responded by saying that the question is “too meaningless to deserve discussion,” that it would be “more accurate” to ask whether we could process pyrite in such a way that someone examining it would be unable to tell it apart from gold, and that if we can so process it, then “the use of words and general educated opinion will have altered so much that one will be able to speak of pyrite as gold without expecting to be contradicted.”  Obviously this would be a bizarre response.  Whether pyrite might be taken by someone to be gold and whether pyrite is in fact gold are just two different questions, and what I would be doing is simply changing the subject rather than in any way answering the original question.  How is Turing’s procedure any different?  And how exactly is “Can machines think?” any more “meaningless” than “Is pyrite gold?”
It’s no good, by the way, to object that the cases are not parallel insofar as an expert could distinguish gold and pyrite.  The cases are parallel in this respect, as Turing himself implicitly admitted.  Copeland points out (p. 211) that Turing elsewhere acknowledged that in a Turing Test situation, someone with expertise about machines might well be able to figure out from subtle clues which is the machine.  Turing thus stipulated that the interrogator should be someone who does not have such expertise.  He thought that what mattered was whether the ordinary person could figure out which is the machine.  So, whether an expert (as opposed to an ordinary observer) could figure out whether or not something is pyrite does not keep my example from being relevantly analogous to Turing’s.
So, why might Turing or anyone else think that his proposed test casts any light on the question about whether machines can think?  There are at least three possible answers, and none of them is any good.  I’ll call them the Scholastic answer, the verificationist answer, and the scientistic answer.  Let’s consider each in turn.
What I call the “Scholastic answer” is definitely notwhat Turing himself had in mind, though in fact it would be the most promising (if ultimately unsuccessful) way to try to defend Turing’s procedure.  The idea is this.  Recall that it is a basic principle of Scholastic metaphysics that agere sequitur esse (“action follows being” or “activity follows existence”).  That is to say, the way a thing acts or behaves reflects what it is.  A defender of the Turing Test could argue that if a machine acts like an intelligent thing, then it must be an intelligent thing.  But competent language use is a paradigmatically intelligent activity (especially for a Scholastic, who would define intellect in terms of the grasp of abstract concepts of the sort expressed by general terms).  Hence (so the argument might go) the Turing Test is a surefire way to test for intelligence.
But not so fast.  For a Scholastic, the principle agere sequitur esse must, of course, be applied in conjunction with other basic metaphysical principles.  And one of the other relevant ones is the distinction between substantial form and accidental form, a mark of which is the presence or absence of irreducible causal powers.  A plant carries out photosynthesis and a pocket watch displays the time of day, but these causal powers are not in the two objects in the same way.  That a plant carries out photosynthesis is an observer-independent fact about the plant, whereas that a watch displays the time of day is not an observer-independent fact about the watch.  For the metal bits that make up the watch have no inherenttendency to display the time.  That is a function we have imposed on them, from outside as it were.  The plant, by contrast, does have an inherent tendency to carry out photosynthesis.  That reflects the fact that to be a plant is to have a substantial form and thus to be a true substance, whereas to be a pocket watch is to have a mere accidental form and not to be a true substance.  The true substances in that case are the metal bits that make up the watch, and the form of a pocket watch is just an accidental form we have imposed on them.  (I have discussed the difference between substantial and accidental form in many places, such as here, here, and here.  For the full story, see chapter 3 of Scholastic Metaphysics .) 
Now, a computing machine is like a pocket watch rather than like a plant.  It runs the programs it does, engages in conversation, etc. in just the same way that the watch displays the time.  That is to say, it has no inherenttendency to do these things, but does them only insofar as we impose these functions on the parts that make up the machine.  (This is why, as Saul Kripke points out, there is no observer-independent fact of the matter about what program a computer is running, and why, as Karl Popper and John Searle point out, there is no observer-independent fact of the matter about whether something even counts as a computer in the first place.)  To be a computer is to have a mere accidental form rather than a substantial form.
In applying the principle agere sequitur esse, then, we need to determine whether the thing we’re applying it to is a true substance or not, or in other words whether it has a substantial form or merely an accidental form.  If we’re examining bits of metal and find that they display the time, it would silly to conclude “Well, since agere sequitur esse, it follows that metal bits have the power to tell time!”  For the bits are “telling time” only because we have made them do so, and they wouldn’t be doing it otherwise.  Similarly, if I throw a stone in the air, it would be ridiculous to conclude “Since agere sequitur esse, it follows that stones can fly!”  The stone is “flying” only because and insofar as I throw it.  Flying is, you might say, merely an accidental form of the stone.  What matters when applying the principle agere sequitur esse is to see what a thing does naturally, on its own, when left to its own devices-- that is to say, to see what properties flow or follow from its substantial form, as opposed to the accidental forms that are imposed upon it.
Now, seen in this light the Turing Test is just a non-starter.  To determine whether a machine can think, it simply isn’t relevant to find out whether it passes the Turing Test, if it passes the test only because it has been programmed to do so.  Left to themselves, metal bits don’t display time, and stones don’t fly.  And left to themselves, machines don’t converse.  So, that we can make them converse no more shows that they are intelligent than throwing stones or making watches shows that stones have the power of flight or that bits of metal qua metal can tell time.
So, while the Scholastic answer would (in my view, since I’m a Scholastic) be Turing’s best bet, at the end of the day it doesn’t really work.  But of course, Turing was no Scholastic.  Did he have in mind instead what I call the “Verificationist answer”?  The idea here would be this: The meaning of a statement is, according to verificationism, determined by its method of verification.  Now, we can’t peer into anyone else’s mind, in the case of human beings any more than in the case of machines.  So (the argument might continue), the only way to verify whether something is intelligent is to determine whether it behavesin an intelligent way, and intelligent conversation is the gold standard of intelligent behavior.  Hence the only way the question “Can machines think?” can be given a meaningful construal is to interpret it as asking whether machines can behave in an intelligent way.  Since that is precisely what the Turing Test seeks to determine, if a machine passes it, then there is nothing more that could in principle be asked for as evidence that it is genuinely intelligent.  Indeed (so the argument would go), there is nothing more for intelligence to be than the capacity to pass the Turing Test.
Now, verificationism was certainly in the air at the time Turing was writing.  It underlay the “philosophical behaviorist” view that having a mind is “nothing but” manifesting certain patterns of behavior or dispositions for behavior.  But there are serious problems with verificationism, not the least of which is that it is self-defeating.  For the principle of verification is not itself verifiable, which entails that it is, by its own standards, strictly meaningless.  If it were true, then it wouldn’t even rise to the level of being false.  Unsurprisingly, no one defends it any more, at least not in its most straightforward form.
But Turing does not in any case appeal to verificationism in the paper, and I don’t think that’s really what’s going on.  What I think he was at least tacitly committed to is what I call the “Scientistic answer” to the question of why anyone should think the Turing Test casts light on the question whether machines can think.  Turing’s view, I suspect, was essentially that there is no way to study intelligence scientificallyother than by asking what a system would have to be like in order to pass the Turing Test.  Hence that is, in his view, the question we should focus on.  Notice that this is not (or need not) be the same position as that of the verificationist.  His talk about “meaninglessness” notwithstanding, Turing need not say that it is strictlymeaningless to ask whether something could pass the Turing Test and yet not truly be thinking.  He could say merely that since there is no scientific way to investigate that particular question, there is no point in bothering with it, and we should just focus instead on what the methods of the empirical scientist might shed light on.
If this is what Turing is up to, then he is essentially doing the same thing Lawrence Krauss does when he pretends to answer the famous question why there is anything at all rather than nothing.  And what Krauss does, as I have discussed several times (here, here, here, and here), is to pull a bait-and-switch.  He pretends at first that he is going to explain why there is something rather than nothing, but then changes the subject and discusses instead the question of how the universe in its current state arose from empty space together with the laws of physics -- which, of course, are very far from being nothing.  His justification for this farcical procedure is essentially that physics has something to tell us about the latter question, whereas it has nothing to tell us about why there is anything at all (including the fundamental laws of physics themselves) rather than nothing.  What we should focus on, in Krauss’s view, is the question he thinks he can answer rather than the question we originally asked.
Now this is exactly the same fallacy as that of the drunk who insists on looking for his lost car keys under the lamp post, on the grounds that that is the only place where there is enough light by which to see them.  The fact that that is where the light is simply doesn’t entail that the keys are there, and neither does it entail that there is any point in continuing to look for the keys under the lamp post after repeated investigation fails to turn them up, or that there is no point in trying to find ways to look for the keys elsewhere, or that we should look for something else under the lamp post rather than the keys.  Similarly, the fact that the methods of physics are powerful methods doesn’t entail that those methods can answer the question why there is anything at all rather than nothing, or that we should replace that question with some other question that the methods of physics can handle, or that there is no point in looking for other methods by which to investigate the question.  To assume, as Krauss does, that the question simply must be one susceptible of investigation by physics if it is to be rationally investigated at all is to commit what E. A. Burtt identified as the fallacy of “mak[ing] a metaphysics out of [one’s] method” -- that is, of trying to force reality to conform to one’s favored method of studying it rather than conforming one’s method to reality. 
Turing seems to be guilty of the same thing.  Rather than first determining what thought isand then asking what methods might be suitable for studying something of that nature, he instead starts by asking what sorts of thought-related phenomena might be susceptible of study via the methods of empirical science, and then decides that those are the only phenomena worth studying.  The fallaciousness of this procedure should be obvious.  Characterizing “thought” as the kind of thing that a machine would exhibit by virtue of passing the Turing Test is like characterizing “keys” as the sort of thing apt to be found under such-and-such a particular lamp post.
In general, there is (as I have argued many times) simply no good reason to accept scientism and decisive reason to reject it.  There are at least five problems with it: First, formulations of scientism are typically either self-defeating or only trivially true; second, science cannot in principle offer a complete description even of the physical world; third, science cannot even in principle offer a complete explanation of the phenomena it describes; fourth, the chief argument for scientism -- the argument from the predictive and technological successes of science -- is fallacious; and fifth, the widespread assumption that the only alternative to natural science is a dubious method of doing “conceptual analysis” is false.  (See chapter 0 of Scholastic Metaphysics for detailed exposition of each of these points.)  So, the “Scientistic answer” also fails.
Needless to say, Turing was a brilliant scientist, and all of us who use and love computers are in his debt.  But his foray into philosophy resulted, I think, not in any positive contribution but only in an interesting and instructive mistake.

What’s the deal with sex? Part II

In a previous post I identified three aspects of sex which manifestly give it a special moral significance: It is the means by which new human beings are made; it is the means by which we are physiologically and psychologically completed qua men and women; and it is that area of human life in which the animal side of our nature most relentlessly fights against the rational side of our nature.  When natural law theorists and moral theologians talk about the procreative and unitive functions of sex, what they have in mind are the first two of these aspects.  The basic idea of traditional natural law theory where sex is concerned is that since the good for us is determined by the natural ends of our faculties, it cannot be good for us to use our sexual faculties in a way that positively frustrates its procreative and unitive ends.  The third morally significant aspect of sex, which is that the unique intensity of sexual pleasure can lead us to act irrationally, is perhaps less often discussed these days.  So let’s talk about that.Aquinas provides illuminating guidance on our subject in his discussion in the Summa Theologiae of the eight “daughters” or effects of lust.  Keep in mind that “lust,” when used pejoratively by Aquinas and other natural law theorists and moral theologians, does not mean “sexual arousal.”  There is nothing wrong with sexual arousal, even intense sexual arousal, in itself.  Rather, “lust” is used in natural law theory and moral theology as a technical term for sexual desire that is in some way disordered.  In what sense might it be “disordered”?  Aquinas writes:

A sin, in human acts, is that which is against the order of reason.  Now the order of reason consists in its ordering everything to its end in a fitting manner.  (Summa Theologiae II-II.153.2)
So, reasonable or well-ordered sexual desire is sexual desire that is “order[ed]… to its end” and “in a fitting manner.”  Thus, sexual desire is unreasonable or disordered if it is indulged in a way that frustrates its natural ends, or if it is indulged in an unfitting manner.
Disorder of the kind that involves frustration of the natural ends of sexual desire would in Aquinas’s view exist when, for example, such desire is directed at something other than a human being of the opposite sex, or when the sexual act is prevented from reaching its natural climax in insemination.  An example of sexual desire that is disordered in its manner would be adulterous sexual desire.  Suppose you find some person of the opposite sex other than your spouse attractive.  So far there is no sin.  Suppose that sexual thoughts and images about this person enter unbidden into your consciousness.  So far, still no sin.  But now suppose that instead of pushing these thoughts and images out of your mind and turning your attention to something else, you willingly and actively entertain them.  Now there is a sin of lust.  Finding this other person attractive is of itself perfectly natural, and in the right circumstances (being married to the person) there would be nothing wrong with letting this attraction draw you into sexual fantasy and intense arousal.  But because you are not married to the person and are married to someone else, circumstances make such fantasy and arousal disordered and sinful. 
For present purposes, though, I will put to one side questions about what sorts of desire and behavior, specifically, count as lustful or disordered.  Controversies over the natural law position on extra-marital sex, homosexuality, contraception, etc. are not to the present point.  (I have addressed those matters in other places, such as here.)  For our topic here is primarily not lust itself but rather the “daughters” or effectsof lust -- the way in which sexual desire that is disordered tends to bring further moral disorders in its wake.
One more preliminary note: To say that some further moral disorder is an effect of lust is not to say that it invariably and fully follows from lust.  We are talking here about tendencies.  The longer and more thoroughly someone’s sexual desires are disordered, the more likely he is to fall into the other moral disorders Aquinas speaks of.  But if sexual desire is less thoroughly disordered, or if the disorder is counteracted by efforts to correct it, then naturally the secondary disorders are less likely to follow, or will not be as great as they otherwise would be.
The daughters of lust
Of the eight “daughters of lust,” the first four concern the intellect and the last four the will.  The first “daughter” or effect is what Aquinas calls “blindness of mind,” whereby the “simple [act of] understanding, which apprehends some end as good… is hindered by lust.”  What Aquinas has in mind here can be understood as follows.  The intellect has as its natural end or final cause the grasp of truth.  Truth, however, is a “transcendental,” as is goodness, and the transcendentals are convertible with one another.  That is to say, truth and goodness are really the same thing looked at from different points of view.  Hence the intellect is no less naturally directed toward the grasp of the good as it is toward the grasp of truth.  (See pp. 31-36 of Aquinas for discussion of the transcendentals.) 
Now, when, for whatever reason, we take pleasure in some thing or activity, we are strongly inclined to want to think that it is good, even if it is not good; and when, for whatever reason, we find some idea attractive, we are strongly inclined to want to think that it is true and reasonable, even if it is neither.  Everyone knows this; you don’t have to be a Thomist to see that much.  The habitual binge drinker or cocaine snorter takes such pleasure in his vice that he refuses to listen to those who warn him that he is setting himself up for serious trouble.  The ideologue is so in love with a pet idea that he will search out any evidence that seems to confirm it while refusing to consider all the glaring evidence against it.  The talentless would-be actor or writer is so enamored of the prospect of wealth and fame that he refuses to see that he’d be better advised to pursue some other career.  And so forth.  That taking pleasure in what is in fact bad or false can impair the intellect’s capacity to see what is good and true is a familiar fact of everyday life.
Now, there is no reason whatsoever why things should be any different where sex is concerned.  Indeed -- and this is part of Aquinas’s point -- precisely because sexual pleasure is unusually intense, it is even more likely than other pleasures are to impair our ability to perceive what is true and good when what we take pleasure in is something that is in fact bad.  In particular, habitually indulging one’s desire to carry out sexual acts that are disordered will tend to make it harder and harder for one to see that they are disordered.  For one thing, the pleasure a person repeatedly takes in those acts will give the acts the false appearance of goodness; for another, the person will be inclined to look for reasons to regard the acts as good or at least harmless, and disinclined to look for, or give a dispassionate hearing to, reasons to think them bad.  Hence indulgence in disordered sexual behavior has a tendency to impair one’s ability to perceive the true and the good, particularly in matters of sexual morality.  In short, sexual vice makes you stupid.
Even here you don’t need to be a Thomist to see that much.  Everyone knows that overindulgence in sexual pleasure can blind someone to the likely bad effects of such indulgence.  In particular, everyone is familiar with examples like that of the lecherous boss or teacher who sexually pursues subordinates or students despite the risks to his family or career, the woman who deludes herself into thinking that the married man she is having an affair with will leave his wife and marry her, the pornography user who refuses to admit that he is addicted, and so on. 
Of course, there are lots of things the Thomist regards as sexually disordered which many people these days do not regard as disordered.  In part this is, from a Thomist point of view, a consequence of widespread intellectual error.  For when the general metaphysical framework underlying traditional natural law theory -- essentialism, teleological realism, and so forth -- is properly understood, it is pretty obvious that the general natural law approach to sexual morality is perfectly reasonable, and indeed pretty hard to avoid, given that metaphysical framework.  Moreover, the framework itself is not only perfectly defensible, but also (as I have argued at length) pretty hard to avoid when properly understood.  The trouble is that in contemporary intellectual life most people know nothing of, or at best know only crude caricatures of, that metaphysics and of the traditional natural law theory that rests on it.  Hence they fail to understand the rational foundations of traditional sexual morality.
But the Thomist is bound to judge that mereintellectual error is not the only problem.  For it’s not just that people in contemporary Western society commonly disagree, at an intellectual level, with the natural law theorist’s judgments about what is disordered.  It’s that they commonly act in ways that natural law theory says are disordered.  And if such behavior has a tendency to impair one’s capacity to perceive what is true and good, especially where sex is concerned, then it follows that widespread rejection of traditional sexual morality is bound to have as much to do with the sort of cognitive corruption that Aquinas calls “blindness of mind” as it does with the making of honest intellectual mistakes.  That people who don’t behave in accordance with traditional sexual moral norms also don’t believethat these norms have any solid intellectual foundation is thus in no way surprising.  On the contrary, that’s exactly what natural law theory itself predicts will happen.
It is in light of this fact that we need to evaluate the refusal of some contemporary academic philosophers even to consider arguments in defense of traditional sexual morality.  Those who take this attitude claim that such arguments need not be taken seriously because they are mere expressions of “bigotry.”  Now, one problem with this position is that it is manifestly fallacious.  It either begs the question, since whether traditional sexual morality really is “bigoted” rather than rationally justifiable is precisely what is at issue; or it is a fallacious ad hominem, an attempt to dismiss the arguments on the basis of the purportedly disreputable motivations of those who put them forward. 
Another problem, though, is that this strategy of dismissing the arguments for traditional sexual morality as mere rationalizations of “bigotry” can be stalemated by the counter-accusation that those who reject traditional sexual morality suffer from what Aquinas calls “blindness of mind.”  The traditional moralist might respond: “Of course you would dismiss the arguments as mere bigotry!  That’s because your intellect has been so clouded by sexual vice that you cannot even see what is good and true where sex is concerned, and don’t even want to try to see it!”
Of course, if the Thomist left it at that and merelyaccused the other side of blindness of mind, he too would be guilty of begging the question or of a fallacious ad hominem.  What that shows, though, is that there is simply no rational way to avoid engaging in debate with those with whom you disagree on the subject of sexual morality.  If the defender of traditional sexual morality is to avoid resorting to a mere question-begging ad hominem, then he has to give arguments for his position and to answer the arguments of the other side.  And if the critic of traditional sexual morality is to avoid resorting to a mere question-begging ad hominem, then he too has to give arguments for his position and to answer the arguments of the other side.  It is the side that merely flings abuse at its opponents and refuses to engage in debate that is the truly bigoted side. 
But I digress.  The other three “daughters of lust” that concern the intellect follow straightforwardly from blindness of mind.  The second is what Aquinas calls “rashness,” which concerns the way disordered sexual desire hinders “counsel about what is to be done for the sake of the end.”  What Aquinas means here is that just as pleasure in what is disordered can blind us to the true ends of our sexual faculties, so too can it blind us to the means to achieving those ends. 
The third daughter of lust is what Aquinas calls “thoughtlessness,” and what he appears to have in mind is a failure of the intellect even to attend to ends and means in the first place.  In other words, whereas “blindness of mind” involves the intellect’s attending to the question of the ends of sex but getting them wrong, and “rashness” involves the intellect’s attending to the question of the means of achieving those ends and getting those wrong too, “thoughtlessness” involves the intellect’s not even bothering with the question of what ends and means are proper.  The “thoughtless” man simply pursues the disordered pleasures to which he has become addicted in something like a sub-rational way, “mindlessly” as it were.  His intellectual activity vis-à-vis sex no longer rises even to the level of rationalization.
The fourth daughter of lust is “inconstancy.”  Here the idea seems to be that even when the lustful person is not utterly sunk in “blindness of mind,” “rashness,” and “thoughtlessness” and thus still has some grasp of the proper ends and means vis-à-vis sex, that grasp is nevertheless tenuous.  The pleasure of disordered sexual behavior constantly diverts the intellect’s attention, so that what is truly good is not consistently perceived or pursued.
Now, for Aquinas, will follows upon intellect, and thus, unsurprisingly, the daughters of lust include four disorders of the will in addition to the four disorders of the intellect.  Aquinas describes the fifth and sixth daughters of lust as follows:
One is the desire for the end, to which we refer "self-love," which regards the pleasure which a man desires inordinately, while on the other hand there is "hatred of God," by reason of His forbidding the desired pleasure.
“Self-love,” it seems to me, can be understood as follows.  The “thoughtless” person is entirely sunk in his disordered sexual pleasures.  The person manifesting “blindness of mind” and “rashness” is also sunk in disordered sexual pleasure, but has managed to cobble together a network of rationalizations for his pursuit of these disordered pleasures.   Either way, though, the lustful person’s focus has turned inward, on the self and its own pleasures and intellectual constructions, rather than outward, toward what is actually good and true.  The mind corrupted by lust wants to make reality conform to itself, rather than to make itself conform to reality.  Hence the very idea that there is such a thing as a natural, objective moral order, especially where sex is concerned, becomes unbearable to the lustful person. 
The sequel, naturally, is what Aquinas calls “hatred of God.”  For God is Being Itself, and since being, like truth and goodness, is a transcendental, it follows that God is also Truth Itself and Goodness Itself.  These are all just different ways of conceptualizing the same one divine reality.  Thus, to hate what is in fact true and good is ipso facto to hate what is in fact God.  Of course, the person lost in disordered sexual desire might claim to love God.  If such a person knows he is lost in disordered desire and seeks to be freed from it, this love is sincere.  He still has some perception of what is truly good and wants to strengthen his grasp of it and his ability to pursue it.  But suppose the person loves his disordered desires, hates those who would call him away from indulging those desires, and refuses to take seriously the suggestion that such indulgence is contrary to the divine will.  Then his purported love of God is bogus.  It is not really God that he loves at all, but rather an idol of his own construction. 
The last two daughters of lust are what Aquinas calls “love of this world” and “despair of a future world.”  Now, for Aquinas a human being qua rational animal has both corporeal powers (namely our animal powers of nutrition, growth, reproduction, sensation, appetite, and locomotion) and the incorporeal powers of intellect and will.  It is the latter, higher powers that make our souls immortal and destined for a life beyond the present one.  Since our animal powers, and the pleasure associated with their exercise, are natural to us, there is nothing wrong with our loving these things.  But by “love of this world” what Aquinas has in mind is an excessivelove of these things.  Disordered sexual pleasure, by virtue of its intensity, has a tendency to turn us away from the goods of the intellect.  In part this is because such pleasure blinds us to what the intellect would otherwise see to be true and good, but also in part because even where the lustful person can still perceive truth and goodness, its pursuit is difficult since the pleasure he might take in it is so much less intense than the disordered sexual pleasure to which he is in thrall.
Naturally, then, the lustful person is bound to be uninterested in the next life, and disinclined to do what is needed to secure his future well-being within it.  It will seem cold, abstract, and dull compared to what he has set his heart on in this life.  And thus it is no surprise that Christian theologians have traditionally emphasized the dangers sexual sins pose to one’s immortal soul.  This is not because such sins are the worst sins -- they are not -- but rather because the pleasure associated with them makes them very easy to fall into and, if they become habitual, very difficult to get out of.  (Churchmen who want to downplay the significance of sexual sins in the name of compassion are thus acting in a way that is in fact anything but compassionate.)
The opposite extreme
So far we have been talking about sins of excess where sexual pleasure is concerned.  But it is very important to keep in mind that here as in other areas of human life, there are disorders of deficiency as well as disorders of excess.  Speaking of pleasure in general, Aquinas writes:
Whatever is contrary to the natural order is vicious.  Now nature has introduced pleasure into the operations that are necessary for man's life.  Wherefore the natural order requires that man should make use of these pleasures, in so far as they are necessary for man's well-being, as regards the preservation either of the individual or of the species.  Accordingly, if anyone were to reject pleasure to the extent of omitting things that are necessary for nature's preservation, he would sin, as acting counter to the order of nature.  And this pertains to the vice of insensibility. (Summa Theologiae II-II.142.1)
Aquinas immediately goes on to note that it is possible to forsake pleasure in a way that is not vicious, as when one chooses celibacy for the sake of the priesthood or religious life.  There are also unusual cases where even spouses might agree to abstain from sex for spiritual reasons.  But these are not (or should not be) cases where sexual pleasure is rejected as bad, but rather cases where it is regarded it as good but nevertheless forsaken for the sake of something even better.  And the normal course of human affairs is for people to marry, and when they marry to have sexual relations.  That means that sexual pleasure is simply a normal part of ordinary human life.  That is inevitable given that we are, by nature, as much corporeal and animal creatures as rational ones.  A “vice of insensibility” vis-à-vis sexual pleasure would, accordingly, plausibly be manifest in a marriage where one spouse refuses to make love, or does so only grudgingly, or does so willingly but with complete lack of interest, the way one might without protest agree to do the dishes or take out the trash.  (Of course, spouses are sometimes ill, or tired, or stressed out, or otherwise just not in the mood and thus would rather not have sex.  There’s nothing necessarily wrong with that.  The problem is when one spouse exhibits a habitual aversion to or disinterest in sex.) 
Just as the will might be insufficiently drawn toward sexual pleasure, so too can the intellect take too negative a view of it.  For example, some Christian theologians of earlier centuries were suspicious of sexual pleasure, and erroneously regarded it as something that attends sexual intercourse only as a result of original sin.  Aquinas rejected this view, and in the centuries since his time, natural law theorists, moral theologians, and the Magisterium of the Catholic Church took an increasingly more positive view of sexual pleasure as nature’s way of facilitating the procreative and unitive ends of sex.
So just what is the deal with sex, anyway?  Why are we so prone to extremes where it is concerned?  The reason, I would say, has to do with our highly unusual place in the order of things.  Angels are incorporeal and asexual, creatures of pure intellect.  Non-human animals are entirely bodily, never rising above sensation and appetite, and our closest animal relatives reproduce sexually.  Human beings, as rational animals, straddle this divide, having as it were one foot in the angelic realm and the other in the animal realm.  And that is, metaphysically, simply a veryodd position to be in.  It is just barely stable, and sex makes it especially difficult to maintain.  The unique intensity of sexual pleasure and desire, and our bodily incompleteness qua men and women, continually remind us of our corporeal and animal nature, pulling us “downward” as it were.  Meanwhile our rationality continually seeks to assert its control and pull us back “upward,” and naturally resents the unruliness of such intense desire.  This conflict is so exhausting that we tend to try to get out of it by jumping either to one side of the divide or the other.  But this is an impossible task and the result is that we are continually frustrated.  And the supernatural divine assistance that would have remedied this weakness in our nature and allowed us to maintain an easy harmony between rationality and animality was lost in original sin. 
So, behaviorally, we have a tendency to fall either into prudery or into sexual excess.  And intellectually, we have a tendency to fall either into the error of Platonism -- treating man as essentially incorporeal, a soul trapped in the prison of the body -- or into the opposite error of materialism, treating human nature as entirely reducible to the corporeal.  The dominance of Platonism in early Christian thought is perhaps the main reason for its sometimes excessively negative attitude toward sexual pleasure, and the dominance of materialism in modern times is one reason for its excessive laxity in matters of sex.  The right balance is, of course, the Aristotelian-Thomistic position -- specifically, Aristotelian-Thomistic philosophical anthropology, which affirms that man is a single substance with both corporeal and incorporeal activities; and Aristotelian-Thomistic natural law theory, which upholds traditional sexual morality while affirming the essential goodness of sex and sexual pleasure.