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10 December 2012


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Helen De Cruz

Here are some of my disconnected thoughts on this discussion (Cautionary preface: I have still not gotten round to reading Nagel's book).
I've noticed that authors like Plantinga, and also more popularizing authors like Timothy Keller (Reason for God, 2008), relish in the fact that Nagel is not a theist AND YET rejects materialism in favor of at least some aspects of intelligent design. They seem to be saying this: See, in Nagel you've got an atheist who rejects Darwinian materialism, and he's such an intelligent and influential philosopher (Nagel is usually given full credentials as a leading philosopher of our days etc in such apologetic Christian writings). The assumption here seems to be that, since it's not just theists who reject materialism, there must surely be rational, worldview-independent grounds for doing so. I find this form of seeking nontheist partisans a questionable way of making arguments against physicalism, so I hope Nagel (and others of his ilk) finally make their minds up and become full-blown theists...
The reason why Nagel hasn't done this so far is indeed fascinating: he doesn't so much weigh the evidence (or philosophical reasons or whatever) for God's existence against God's existence, but seems to be mainly concerned with pragmatic questions (is it a good thing if God exists, the "reassuring explanations" or not, the fear of a loss of privacy?) Plantinga muses that this fear of a constant, Big Brother like monitoring presence is quite common. It has been discussed more in detail in this paper by Guy Kahane (Should we want God to exist, in PPR):
Kahane argues that there is an important downside to theism: " [If theism is true then] everything about us is known and fully understood by another, a world where even our innermost thoughts and feelings are not entirely private. It is a world in which we are never truly alone, away from the presence and attention of another. And if the true nature of God is beyond human comprehension, it would also be a world that we can never hope to fully understand."

Eric Schliesser

In fairness to Nagel, throughout his book he also offers philosophical arguments to explain why he does not accept Theism. I have not studied these very carefully, but some involve non-pragmatic reasons including an appeal to intelligibility (that Theism involves the wrong sort of intelligibility and has the wrong kind of relationship to brute facts), see p. 25). I think the most principled response given Nagel's own philosophy is that Theism involves the wrong kind of point of view, external to the one sought (pp. 21-32).

J Kepler

Helen: "I find this form of seeking nontheist partisans a questionable way of making arguments against physicalism, so I hope Nagel (and others of his ilk) finally make their minds up and become full-blown theists..."

I don't quite follow you here. What frustrates me in this type of debate is the seeming poverty of options. If theism is understood to mean belief in a personal, anthropomorphic deity more or less as described in Semitic religious texts, them a lot of thinking people will check atheism. But of those a significant subset (I suspect) are not convinced that random, meaningless collisions of particles can ultimately account for self-conscious human beings (among other things). So if Nagel or anyone else could help map the conceptual space outside of such limiting options, maybe that would be a good thing?

Eric Schliesser

If Nagel actually carefully mapped the conceptual space outside the options you find un-promising that would have been very helpful. But I think the Hawthorne and Nolan piece is much better than anything else found in Nagel's book.

P. Stovall

Hi Eric,

Thanks for this; it was very thought-provoking. Here are a couple of reflections.

"Given that Nagel explicitly wishes to steer a path in between brute facts and God's agency, his adoption of the Hawthorne and Nolan framework is opportunistic. Moreover, while I am not claiming that the PSR and probabilistic laws must always be in conflict with each other, it is striking that Nagel must embrace as a brute fact that some futures are "more eligible" than others. (Once granted, teleology takes over.) From the point of view of any PSR worth having this is all just extremely arbitrary."

I haven't read the book, and I don't have a dog in the fight. But I would have thought the reasoning went something like this:

First, there's a conception of the principle of sufficient reason. Something like an update-rule when pulling together a diverse body of information: when faced with something unexpected, take the simplest route to integrate it into a new view. In particular, make the least amount of change in one's view when accomodating an unexpected event. That the categories with which we interpret the event are themselves subject to this revision is part of what makes an understanding of the significance of any particular event such a many-headed creature, ever subject to reappraisal as we update our view.

But with this principle in hand, one then looks to nature and our understanding of the organic world, and comes to reason as follows (qualified, as needed, with "as best as we currently understand"):

1. The universe at this stage of its existence, on earth in particular, contains a wide range of biological diversity with deep trenches of complex organization.

2. (some argument for the conclusion that the amount of time that has elapsed hasn't been sufficient to warrant the expectation that there would be anything near this wide or deep a degree of organisation on Earth)

3. PSR: But the observation encoded in the first premise would be sufficiently explained, given what we know in the 2nd, if we posited that the forces governing everything from inert middle-sized dry goods to the ebb and flow of stellar nebulae are the result of stochastic processes that operate to set up feedback patterns across time so that, when conditions are right, the emergence of kinds of thing which would exhibit this degree of organization would be realized.

Thus, the argument runs, given the wide range of development we see across the biosphere, the best explanation is to posit an inherent teleology in a set of fundamentally stochastic laws of nature. I don't know anything about what sorts of grounds one might have for believing that the earth exhibits more complexity than can be accounted for according to our best estimates about the age of the universe, the amount of time that life has been evolving here, the degree of contingency in the processes of evolution, etc. But it strikes me as a perfectly reasonable view, and one that accords the PSR a proper role.

This is, incidentally, a view that would have been at home in the U.S. a century ago, and it is surprising to see the degree of condemnation that views in this vicinity receive today (I don't mean to be implying that you were yourself engaged in this). The generalized use of organicist thinking, transposing the categories of natural selection onto other domains, was a project that occupied American philosophers for generations. Darwin's work hit the academic community here like a tidal wave, and it had the effect of lifting up the nascent idealism, fostered by folks like Emerson and the New England transcendentalists, together with American versions of the Scottish common-sense philosophy then in the air, into wide-ranging speculation (some better researched than others) about social development, the processes of scientific inquiry, the nature of mind vis a vis our neurophysiology, and the character of American society in general (the second edition of Herbert Scheider's _A History of American Philosophy_ details some of this development). The naturalized teleologies that Nagel and Plantinga seem to be raising are the sort of thing that call to mind the views of such diverse thinkers as James and Royce, and it suggests the kind of metaphysics that Peirce's tychism and agapism could have been founded on. But today, in many quarters, these views will make one a pariah.

(At the risk of becoming a pariah, I want to reiterate that I do not have a dog in this fight; but in the interest of authenticity I want to note that from a certain perspective the supernova death of a star looks like nothing so much as a flower seeding the cosmos with the stuff that will be life.)

"Worse, Nagel has an entirely arbitrary distinction between the fundamental non-teleological and the required- for-consciousness-non-fundamental teleological laws. We are not offered an account of the relationship between the two kinds of laws, nor an explanation why the non-fundamental-teleological laws occur in Hilbert spaces (and how the entities inhabiting these connect to consciousness and points of view)."

To ask for an explanation of relation here seems to me to miss the point. Surely the idea is that the laws that specify teleological progression are not ones that govern different kinds of thing from those that govern mechanical causality, such that there is now a new range of entities we are supposing ourselves to have posited. Instead, the mechanical laws of nature are themselves supposed to leave room for a degree of freedom that is, in its temporal unfolding, a developmental process.

For what it's worth, my own view is that teological description constitutes the condition for a certain kind of understanding, one that appertains to organic kinds in particular. Even though we can understand every organic thing as physically constituted by chemical and mechanical processes, to understand those processes as the workings of a living thing one must think them in terms of their role in affording the organic thing its identity, in appropriating and warding off the causal forces of the world around it as means toward its ends. Which is to say that non-agentive teleology is a modality, not a causality. This is not to deny that purposive explanation will coincide with a mechanical/causal one; indeed, it is meant to underwrite that possibility. In characterizing something as non-agentively purposive I make a claim about the mode under which we understand its activity, I do not thereby make a claim about the causal etiology of that activity. Thus, purposive explanation and the attribution of mechanical causation are consistent.

Kent Staley

I haven't read Nagel's book, Eric, but from your description of his view on what teleology requires, I am left a bit puzzled. First, the laws of physics must be indeterministic, yielding at time t only a probability distribution over possible states at a later time t'. Second, the probability of some of those states must be "significantly higher than is entailed by the laws of physics alone." Given the second condition, why bother with the first? If the effect of teleology is to just cross out whatever distribution you get from physics, and replace it with some different distribution, why is any particular constraint on the first distribution (the one "entailed by the laws of physics") even required?

I know it's HIS book, not yours, but I am just wondering if maybe there is something obvious that I'm missing!

Eric Schliesser

No, Kent, I do not think you are missing anything obvious (maybe I am). I think (but it is HIS book) the explanation is that Nagel wants to accept fundamental physics, but not what he calls "neo-Darwinism," so he wants to introduce principles that do not violate fundamental physics.

Eric Schliesser

Thank you for your thoughtful reflections.
First, the varieties of the PSR worth having are considerably more demanding than simple updating rules. They put constraints on what counts as a genuine explanation, and how things hang together. They are very tough on brute facts and arbitrary relations.
Second, it is *Nagel* that demands an "internal relation" (52) between what he calls "physical history" and "mental history." (52) Throughout the book, he is berating competing approaches for lack of intelligibility (and lack of sufficient reason), yet he is positing arbitrary degrees of freedom.
Third,I like your move to focus on modality and not causality when thinking about non-agentive teleoloy that seems a fertile route; it has affinities with dual-aspect theories, but seems fresh and I would be curious to learn more. (But it is not Nagel's approach.)
Fourth, for the record: I think there are HUGE differences between Peirce and James and the ideas promoted by Nagel. (Plantinga is I think a very beast altogether; I doubt Peirce or James would have had much patience with his approach.) I don't feel confident talking about Royce (haven't read enough). Of course, if Nagel had made an effort he could have explained to his readers which anticipations of his views he would like to revive and the way he differs from them.
Finally, there were a lot of converging pressures on the (perhaps temporary) demise of organicist views, a lot of them unrelated to developments in physics, chemistry and biology (and related to unsavory social/political consequences)--but they always remain a live option in some cultural circles so if you are attracted to them I wouldn't despair (you may end up philosopher-king somewhere).

David Wallace

I think what's problematic about Nagel's reasoning, and what leads to (in my view) an entirely appropriate level of condemnation, is that there is no actual argument at step 2 - just an appeal to common sense. Here's the analogous argument structure for gravity:

1. The universe, and Earth in particular, contains lots of things that are falling towards the ground.

2. (Some argument for the conclusion that the degree of curvature of spacetime in our vicinity hasn't been sufficient to warrant the amount of falling we observe.)

3. But the observation in the first premise would be adequately explained, given what we know in the 2nd, if we posited that objects have a teleological inclination to fall.

As an argument form, that's completely worthless unless the IOU in step 2 can be cashed; likewise with Nagel.

You say, "I don't know anything about what sorts of grounds one might have for believing that the earth exhibits more complexity than can be accounted for according to our best estimates about the age of the universe, the amount of time that life has been evolving here, the degree of contingency in the processes of evolution, etc." Indeed; neither does Nagel. You say "it sounds like a perfectly reasonable view"; many things do. Prima facie reasonableness is just terrible as grounds for advancing a criticism of a scientific program.

To be blunt, Nagel's argument reminds me a little of South Park:
Step 1: Demonstrated that the world contains a large amount of biological complexity.
Step 2: ?????

None of which is to deny that it's abstractly interesting to ask how fundamental teleology would be represented in the laws of physics. (Actually, I think certain aspects of the formalism of quantum theory make it possible to do what Hawthorne and Nolan want very elegantly.)

P. Stovall

1. I'm not sure what you mean by the PSR's constraints being tough on brute facts and arbitrary relations (if I'm reading you right). I was thinking that the inference, from the observed complexity of the world to the supposition of teleology, was the basic unit. In that context, the PSR looked to me like little more than an update rule. I didn't mean that to exclude other roles it might play, but for the purpose of underwriting that inference I think the fairly minimal constraints of the kind I suggested by the update rule look to be enough. But I worry that I'm running together the PSR and an inference to the best explanation.

2. Ah, so Nagel himself looks to an interface between physical and mental histories. But as you say he speaks of this as an internal relation--one might hope this was preparatory for an aufheben. And what's wrong with positing 'arbitrary degrees of freedom'?

3. I would be interested to know more about the differences between Nagel's views and those of Peirce and James. Perhaps a new post at some point? And I don't know how quickly I'd say that James or Peirce wouldn't have 'patience' with Plantinga. Plantinga has done some very good work in modal logic, epistemology, and the philosophy of religion. These three philosophers would have had much to talk about, I think. But then, I don't really know what sort of patience you're talking about here, and it comes off as a snipe more than anything else.

4. Not having read Nagel, I can't comment on his appropriation and engagement with the tradition in which he is writing. But I agree that any philosopher worth her salt must anticipate how she will be received and telegraph her commitments accordingly.

5. What was the bit about unsavory social/political consequences in the demise of organicism? At any rate, I don't contest that the forces overturning the kind of speculation that gripped American philosophers at the turn of the last century were many and varied. The character of conventional academic sentiment has come a long way since the Harvard of Royce and James. If the left has taught us anything, we cannot understand that shift unless we understand it in the context of the sources of power, ideologies, and privileges that sustain the academy as an institution. I suspect there's a critique of the 'left' to be had by looking at the changes in academia over the last century that underwrite the unabashed scorn one sometimes sees cast against religious sentiment today. But then I imagine that one could point out all sorts of blindspots in our various efforts to make thing better for those around us. And as I say, I really don't have a stake either way.

Personally I'm of the mind that the left/right distinction needs to be seriously reworked before it can be put to any substantive use. Sometimes I suspect the urge to line things up along that dichotomy positively suppresses awareness of issues that would otherwise be salient, and blocks off avenues for pursuing certain kinds of development.

P. Stovall

Thanks; this is helpful. I'll pick up the Hawthorne and Nolan piece.

If the argument comes down to an appeal to common sense then I'm pretty underwhelmed. You're right to point out that reasonableness is not warrant; we might also note that the inclination to draw an inference is not an entitlement to do so. But I guess if one is gripped by a conviction there will be an urge to articulate it, and to show that it is warranted. That sort of practice needs to be undertaken with care, though, and we ought to be suspicious of warrants underwritten by little more than the conviction of those who offer them to us. The appeal to common sense is a step up from that, I suppose.

Eric Schliesser

1. Yes, I think you are running together IBE and PSR. (I provided a link to the SEP article on the PSR and that provides a useful introduction.)
2. Nothing wrong with arbitrary degrees of freedom, but it is odd if that is being promoted by somebody embracing PSR and intelligibility requirements.
3. It's not high my agenda, but some posts on Peirce (more Jeff Bell's interest) and James would be fun.
4. Organicism got intermingled with social Darwinist idea and various ways that promoted social hierarchy.

Not sure we really ought to wish the return of organicist views (which are still fairly common in Europe).

We agree that standard dichotomies often prevent alternative views from being seen or stated.

I find it sad that a form of moral and political pluralism that existed in American pre-analytic philosophy got displaced
by more technocratic approaches that favor varieties of moral/political monism. But, we have to play the
cards we are dealt.

Kent Staley

That is what I suspected, Eric. It seems to me that he violates fundamental physics either way. If the teleology-induced probability distribution disagrees with the physics-induced distribution, it is a contradiction, whether the latter is all concentrated on one possibility with probability one or not!

Torin Doppelt

I'm not sure why there would be a connection between teleology and the PSR. In Spinoza's case, the effect seems to be the opposite (to divest nature of the whimsical teleology of freely-willing (freewheeling?) supernatural power).

I also think Michael Della Rocca has written a very interesting paper in support of the PSR that may be of interest here:

One lesson that could be drawn from this, in support of part of what Eric said above, is that the invoking of a demand for "explicability" at one stage in an argument generates a demand (on grounds of consistency, if not logic) that this not be violated later in the same argument. Unless, of course, some sufficient reason could be given for treating some later premise as non-arbitrarily not subject to the demands of explicability. But isn't this absurd?

Eric Schliesser

I think the idea is, Kent, that the teleology-induced probability does not disagree with the physics-induced probability.
But it is underdeveloped how it is supposed to work. 

Eric Schliesser 

Eric Schliesser

Just to be clear: I did not mean to cast aspersions on the PSR, Torin. I have been reflecting on Della Rocca's work on the PSR for quite some time and learned a lot from it. But I also think that without the history surveyed by Lovejoy (and there is a lot more intricate detail missing from that), we are also reinventing wheels and miss the wider issues.
On teleology and the PSR; here I am agnostic about the nature of their relationship.
But, yes, once one opens the door to the PSR it is like a universal acid in the way you put your finger on.

Chris Rawls

Just a brief note. Eric, thanks for this very informative post. In having the wonderful experience of hearing Della Rocca give a Spinoza paper at the Spinoza Society in Rijnsburg once, knowing that he has many good points to make about Spinoza and the PSR, I also heard an equally good critique of his position as circular by another Spinoza scholar. What strikes me as additional interesting questions about Spinoza and the PSR (I realize that this post was about Nagel so I digress a bit) is our reliance on only E1p11 to make this argument out of the entire work. In my reading of his Ethics, the Epicurean tendency to combine physics with ethics and metaphysics applies quite often. One difficulty here is that Spinoza defines language as inadequate knowledge. I wonder, in other words, if we are required by the development of reason to verbally explain what we recognize when having insights which are common notions? In other words, I am sometimes curious if verbal explanations are absolutely required to prove to ourselves that we have clear and distinct, certain knowledge? The latter is adequate, but language is always inadequate and partially constructed. This linguistic measure is an entirely different question though, I realize.

In Leibniz I have found that there may be two versions of the PSR. When I think of Spinoza's system as one substance in which there are infinite ways in which it can express itself, and in which all things are connected through causal chains, when reflecting on E1p11, which cause do we decide is the most important? If this question does pose an important problem, then I wonder if the critique of Della Rocca's position is correct? In other words, to say that we understand adequately that every effect has a cause is not to also assume that we can locate that cause or describe it perfectly in isolation. I personally feel this is an important distinction to make. I understand that it does nothing for the modern day scientific world view (although Spinoza was an advocate of experimentation coupled with theory) to draw this distinction because it relies so heavily, rightfully so, on empirical evidence to demonstrate causes of effects etc., but perhaps positing the PSR in Spinoza in total as his underlying method and proof of his system appears to me to be a problem of infinite regress (possibly) due to his insistence on such foundational notions as that which is self-caused and self-causing, as well as that which is both one substance, eternal, absolutely non-teleological. As well, I would be interested in looking more here at the difference between his notion that every effect "involves" its cause, which varies in interpretation, and E1p11... I find it possible to show that in some contexts we are discussing causes, but in other contexts those same causes can be reasonably and logically demonstrated or defined as effects. This creates further complications for the theory that Spinoza relies so heavily on the PSR. I think...

Eric Schliesser

Chris, there is a lot in your comment (and I am not sure I understand it all). I think Spinoza has a few versions of the PSR, too. I suspect quite a few people think that Della Rocca's position is pushed too far, but there is not much out there. Daniel Schneider has a very interesting forthcoming paper that criticizes aspects of Della Rocca's few. I tend to think that the version of the PSR that I quote above fundamentally applies to eternal truths not to finite modes (for the reasons you hint at). There is some textual problems with my view, but philosophy I think it makes a lot of sense of quite a bit of what Spinoza is doing.

Chris Rawls

Eric, I'll try to be more clear next time, but overall, I agree with you on the many versions of the PSR that we often confuse or rely on etc. Do you happen to know how I can find the Schneider paper or where it will be published? It also sounds like I better get to work trying to publish that part of my dissertation that currently critiques Della Rocca's reading of Spinoza as well.

Eric Schliesser

Schneider is a PhD student at Madison.

Richard Wein

Kent, judging by the account here (I haven't read the book) Nagel's view seems to be in keeping with the common idea that supernatural causes can "override" the laws of physics. But, if the laws of physics are models of how things behave, and if this behaviour can be influenced by supernatural causes, then any laws that don't allow for the effect of supernatural causes are incomplete.

People who talk about supernatural causes overriding the laws of physics seem to see the laws of physics as counterfactual or limited models of how things would behave in the absence of supernatural causes.

Nagel might avoid using any word like "override", but if his teleological cause makes an event "significantly [more likely] than is entailed by the laws of physics alone," he seems to be saying something of the same sort.

Eric Schliesser

Nagel repeatedly insists that his view is far removed from supernatural causation.

Richard Wein

I don't doubt that. But I'm pointing to an apparent similarity.

Eric Schliesser

Yes, it echoes the closing lines of my post above.

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