A review of Sean Carroll's The Big Picture: Part III

Let us continue our review of physicist Sean Carroll's book The Big Picture. In this installment of the review I will be focusing mostly on the section of the book labeled Essence, however, let it be noted that I will also be surveying material from other sections as they seem to fit with many of the topics under discussion presently -- also some material from this section in the book will be held-over and reviewed in the subsequent installment -- mostly that which deals with the philosophy of mind.

In this section of the book Carroll delves into how he believes the world works according to Core Theory and quantum mechanics. He uses these determinations as a springboard into discussing why the universe exists, and how God fits into this picture, or doesn't, as well as the discussion regarding whether there is a soul, and whether or not life will continue after death.

Abducting or deducting God?
Carroll begins to consider worldviews that would oppose his "poetic naturalism" -- one such worldview being that of theism. And what happens when we are confronted with two opposing ontologies that are situated on the same domain? Well, for Carroll it's the method of Bayesian reasoning and abductive logic all the way:

[F]or purposes of this discussion let's imagine that the prior credences for theism and atheism are about equal. Then all the heavy lifting will be done by the likelihoods -- how well the two ideas do in accounting for the world we actually see. (p. 146)

So Carroll's plan is to look at the world and attempt to determine which ontology provides the best explanation for what we see, or don't see. We see evil in the world, then that scores points for atheism. We see consciousness in the world, chalk up a point for theism. Etc.

This might seem a good way to go about inferring which worldview is most reasonable to assume, but I maintain that's it's completely wrongheaded in this instance. First, as I mentioned in one of the previous reviews, abductive (Bayesian) reasoning is not the only kind of reasoning, and more importantly it's not the best kind of reasoning that should be utilized in this discussion. In everyday life and scientific reasoning, abduction is your best friend. If you're a scientist and you find that the liquid in a test tube has changed color, you use inference to the best explanation, plain and simple. But if you're attempting to determine whether the square root of two is a rational or an irrational number, abduction is the wrong tool to use -- you need deduction.

So, why then, should we use deduction when determining whether theism or atheism is true, and not pure abduction, as Carroll would have us do? Well, it comes down to who has the burden of proof: the theist. The theist is saying that there is in fact some positive reality that exists, and it is their burden to prove this. And how do they usually go about attempting to prove it? Through (mostly)logical deduction -- at least that's how the classical theists did it before Paley. [1] Thus, when weighing theism vs atheism, one needs to take the arguments that are being given by theists, which are deductive in nature, and determine whether they hold any merit. Appealing purely to abduction won't do any good, just like appealing to abduction to argue that the square root of two is rational will not be entertained by any mathematician. Contrary to Carroll, the heavy lifting is not done by likelihoods, but by deduction.

The point is that if theistic deductions are valid and sound then no amount of abductive inference will call this into question. And thus what needs to be determined is precisely the matter of if theistic deductions are indeed valid and sound or not -- which, again, is a job of deductive inference.

The more important point is that there are simply some beliefs that are so fundamental and metaphysical that a pragmatic method simply cannot comment on. Like it or not, abduction won't solve the realism/skepticism debate. It won't solve the free will/determinism debate. And it certainly will not solve the theism/atheism debate. Carroll wants to use a screwdriver for every job, when some jobs require a sledgehammer.

Whence the universe?
Carroll commits a whole chapter to exploring the question of why the universe exists, and why there is something rather than nothing. He begins by contemplating the answer of a necessary being in that of God but quickly casts it aside:

Poetic naturalists don't like to talk about necessities when it comes to the universe. They prefer to lay all the options out on the table, then try to figure out what our credences should be in each of them. (p. 196)

First, it's irrelevant that poetic naturalists like Carroll "don't like" to talk about necessities when it comes to the universe. The relevant question is whether talk of necessity is appropriate when it comes to questions of fundamental metaphysics -- of which existential questions like "why is there something rather than nothing?" are a subset -- and surely it is. So, the fact that Carroll is allergic to necessity/contingency talk is not sufficient to cast that talk aside as if it were irrelevant -- and neither has Carroll given any warrant for doing so.

Second, and more importantly, the question being dealt with here is, again, of a significant metaphysical stature, and I don't see that abduction is the right tool to use here. When asking why there is something rather than nothing, what's really being asked is why existence should ontologically precede a complete lack of existence, and this is a deeply metaphysical question in nature, which most likely will have to yield to some type of existential necessity or brute fact -- if you believe in such nonsense. And the fact of the matter is that delving into the nature of existence is commonly a deductive, and not an abductive, endeavor. Thus, the poetic naturalist way of going about answering this detective story is already wrong-headed to begin with.

Nevertheless, let's see the blueprints that Carroll lays out to proceed in answering this question:

Let's start with the relatively straightforward, science-oriented question: could the universe exist all by itself, or does it need something to bring it into existence? [...] All we want to know is "Is the existence of the universe compatible with unbroken laws of nature, or do we need to look beyond those laws in order to account for it?" (p. 196-197)

These are very relevant and important questions to our current inquiry. Carroll attempts to answer these questions by turning to science to settle the debate regarding whether or not the universe had a beginning -- his answer eventually terminating in a modest "we don't know."

The problem here, though, again stems from the fact that Carroll is ignorant to the fact that these are simply not the questions that science can answer in the first place -- "these" questions being the original questions he posed. For even if we could mathematically describe our universe as self-sustaining or existing by itself, this wouldn't actually make any progress in answering the existential question. For science only describes the behavior of that which already naturally exists, and it cannot tell you why the universe behaves in that way in the first place, or why it behaves this way as opposed to another way. To put it in a different vein, in order to have a behavior to describe you first need something which exists and does the behaving, and this means that existence is ontologically prior to behavior. Therefore, no description of behavior (which is all that science is) is sufficient to explain the existence of what does the behaving, and thus, science cannot in principle answer the question of why there is something rather than nothing. Sorry Carroll.

What this also entails, once again, is that Carroll is looking for an answer to the existential question utilizing the wrong tools. Since science cannot aid us in determining why something exists rather than nothing then it is irrelevant, to say the least, when it comes to this particular question -- sorry Lawrence Krauss.

However, Carroll is prepared (or so he thinks) to take on this line of thought:

For questions like this, however, the scientific answer doesn't always satisfy everyone. "Okay," they might say, "we understand that there can be a physical theory that describes a self-contained universe, without any external agent bringing it about or sustaining it. But that doesn't explain why it actually does exist. For that, we have to look outside science." (p. 201)

Yes, this is exactly what I would say. Let's see how Carroll is going to set me straight:

Sometimes this angle of attack appeals to fundamental metaphysical principles, which are purportedly more foundational even than the laws of physics, and cannot be sensibly denied. In particular, the pre-Socratic Greek philosopher Parmenides put forward the famous maxim ex nihilo, nihil fit -- "out of nothing, nothing comes." [...] According to this line of thought, it doesn't matter if physicists can cook up self-contained theories in which the cosmos has a first moment of time; those theories must necessarily be incomplete since they violate this cherished principle.

 This is perhaps the most egregious example of begging the question in the history of the universe. We are asking whether the universe could come into existence without anything causing it. The response is "No, because nothing comes into existence without being caused." How do we know that? It can't be because we have never seen it happen; the universe is different from the various things inside the universe that we have actually experienced in our lives. And it can't be because we can't imagine it happening or because it's impossible to construct sensible models in which it happens, since both the imagining and the construction of models have manifestly happened.  (p. 201-202)

Alright, there's a lot to unpack here. First, notice that Carroll has actually side-stepped the original point that he was claiming to address -- namely, that talk of scientific models doesn't actually address the question of why something exists in the first place. (Note that he does later on say that we may never know why the universe exists, and that its existence might simply be a brute fact. You know what my response is.)

Second, to appeal to fundamental metaphysical principles to call scientific models into question, or to highlight their incompleteness, is not to beg the question. For these principles are seen, by those promulgating them, as necessary conditions of reality; that is, they're seen as conditions that hold in any possible world and are the things that even make science possible in the first place. Thus, to claim that a scientific model cannot overthrow them is not to beg the question. It would beg the question if the individual promulgating said principles had no justification for their necessity. But this would have to be demonstrated by the likes of Carroll, which, to give him credit, he does attempt to do, which brings me to my next, and third, point.

Carroll asks a good question: how does one know that metaphysical principles like the law of causality are immutable? The answer is that we know this because those very propositions are formed through relations of concepts that we abstract from reality, which, as we saw in the last post, we must have objective knowledge of -- on pain of contradiction. Another way to put it is that our knowledge is dictated by reality, and not the other way around, and thus the reason why we know that principles like the law of causality are immutable is because these principles are themselves grounded in the objective nature of reality. [2]

Fourth, it is actually Carroll who begs the question here, though he does it so well that it's hard to catch. To revisit my first point above, he claims that to address the fact that scientific models don't answer the "Why?" of existence, individuals sometimes resort to metaphysical principles. But how does he argue against these principles? By appealing to the very physical models of the universe he already utilized and was questioned on! That is to say, based off of Carroll's argumentation, we could construct the following conversation:

Carroll: We can easily construct physical models of the universe which are self-sustaining.

Me: But those models are purely descriptive and incomplete, and don't answer why something exists in the first place.

Carroll: Where are we to look for this "Why?"

Me: To metaphysical principles like "that which is moved from potency to act is moved by that which is already actual."

Carroll: But this principle is false, since we have already constructed physical models which are self-sustaining.

Round and round we go. Hopefully the attentive reader notices that Carroll would simply keep begging the question regarding his self-sustaining physical models.

Furthermore, the more crucial point is that since science is only quantitatively based, it does not, in its equations, capture notions of causality -- something Carroll has articulated multiple times in the book. Therefore, even though we might be able to construct a model of reality that is self-sustaining, and self-contained, as far as physics is concerned, this does not actually equate to forming a model of the universe that is not contingent upon, and not caused by, anything else. Thus, Carroll's self-sustained models are actually completely irrelevant to the current discussion.

Carroll then briefly returns to the notion of God as an answer to the existential question:

Theists think they have a better answer: God exists, and the reason why the universe exists in this particular way is because that's how God wanted it to be. Naturalists tend to find this unpersuasive: Why does God exist? But there's an answer to that, or at least an attempted one, which we already alluded to at the beginning of this chapter. The universe, according to this line of reasoning, is contingent; it didn't have to exist, and it could have been otherwise, so its existence demands an explanation. But God is a necessary being; there is no optionality about his existence, so no further explanation is required. 

Except that God isn't a necessary being, because there are no such things as necessary beings. All sorts of versions of reality are possible, some of which have entities one would reasonably identify with God, and some of which don't. We can't short-circuit the difficult task of figuring out what kind of universe we live in by relying on a priori principles. (p. 203)

Again, there's a lot to unpack here. First, I want to focus on Carroll's comments on God as a necessary being, for he's only begging the question here. He literally gives absolutely no justification or substantiation for the claim that no necessary beings exist. He hasn't even come close to attempting to do the philosophical leg-work that would warrant him in making such an audacious claim.

Second, the only semblance of an argument Carroll does give in favor of God not being a necessary being is that of the fact that we can conceive of other possible worlds where there no such God. But again, Carroll hasn't done the leg-work to demonstrate this. For if we arrive at a logical deduction of what God is, as classical theists claim we can, then by "God" we literally mean "that whose essence is to exist," which means that by definition God cannot not exist. But this entails that there actually is no world of which we can conceive where God does not exist [3], and thus Carroll is wrong.

Third, Carroll actually refutes himself here when dismissing talk of a priori principles. Remember that Carroll is big on empiricism, and believes that the only way we can have genuine knowledge is to actually look at reality -- thus, a priori philosophy is moot in his eyes. However, Carroll's point in his latter paragraph is predicated on "all sorts of versions of reality" being ontologically possible -- that is, he's employing the notion of modal logic, an a priori endeavor. How does Carroll know that reality enjoys various ontological "possibilities"? He might say, "because of the fact we can imagine them" -- he seems to say as much on page 203. But that immediately commits one to the idea that possibility is grounded in the imagination; yet how would Carroll ground that idea? That is, why does Carroll believe that our imagination is capable of telling us anything true about the nature of reality? The point here that I'm trying to make is that any answers to these questions will necessarily be founded on a priori principles, the very thing Carroll is allergic to and vehemently opposes, as we saw last review. But, were he to give his beliefs a little more thought, he'd see that he ends up falling on his own sword, as it were.

In any event, Carroll conjures up no answer to the existential question of why the universe exists in the first place; though he should not be faulted for this. What he is to be faulted for is his sloppy logic utilized to throw opposing answers, like that of theism, under the bus. And thus it doesn't seem like his poetic naturalism is properly justified.

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[1] Don't get me wrong. I know that many theists have attempted to persuade individuals that God exists by telling them to look at the stars, or the beauty that we perceive in the world etc., and this no doubt is done in the vein of abduction. But this is usually not done to satisfy one's burden of proof, at least in the sense of what we mean by "proof".

[2]Carroll also visits this idea earlier in his book on page 116 wherein he claims that "[beliefs] aren't (try as we may) founded on unimpeachable principles that can't be questioned." But this is false. If you push back on the justifications for propositions of knowledge further and further, you will arrive at a foundation of first principles that are axiomatic and, contrary to Carroll, cannot be questioned.

[3] Note that to imagine is not to conceive, in that I can conceive of something without imagining it and vice versa. Carroll constantly conflates the two throughout his book.

A review of Sean Carroll's The Big Picture: Part II

We are continuing our survey of physicist Sean Carroll's book The Big Picture (Part I here) by moving on to his second section of the book entitled Understanding.

This part of the book is where Carroll puts forward his epistemology, which he calls "poetic naturalism." He does a great job of articulating his case, and is very thorough and covers many topics while not sacrificing depth. In fact, there were many times where I thought to myself "but what about X?" and, sure enough, that would be the very next topic Carroll addressed. Also, Carroll's first chapter in this section is a great primer on Bayesian Reasoning for laymen -- he explains it beautifully with simple and common-sense examples.

Contrary to what many might think, I actually agreed with Carroll on many aspects of his epistemology -- he does make some correct predications. But obviously I do not agree with it all, since it is, after all, a form of naturalism.

That being said, let us dive into the material and see what Carroll has to say.

Bayesian reasoning
Bayesian reasoning, based on Bayes' Theorem, is foundational to abductive reasoning. It gives you, in principle, a very logical and matter-of- fact way of forming beliefs and updating them in light of new observations and information. It is a way of making inferences to the best explanation -- the very type of inferences science is interested in.

I have no qualms about Bayesian reasoning itself, only about when it can, and cannot, be applied. Bayesian reasoning is useful for (and really is) abductive reasoning, however, it is irrelevant to deductive reasoning. For if a deductive argument is sound, then the truth of the conclusion is guaranteed, whereas nothing guarantees an inference predicated on abductive reasoning. On the contrary, abductive reasoning deals with probabilities, and this should make sense since Bayes' Theorem is itself a theorem dealing in probability.

Why is it important to contrast Bayesian inference with deduction here? Well, because Carroll seems to pay little attention to deduction and focuses mainly on abduction (for reasons we'll survey below). This isn't a problem in itself, but it becomes one when one realizes that many arguments that attempt to demonstrate the falsity of naturalism are deductive in nature.

In any event, Carroll also claims the following:

Each of us comes equipped with a rich variety of beliefs, for or against all sorts of proportions. Bayes teaches us (1) never to assign perfect certainty to any such belief; (2) always be prepared to update our credences when new evidence comes along; and (3) how exactly such evidence alters the credences we assign. It's a road map for coming closer and closer to the truth. (p. 82-83)

On first glance this seems like a great point, and I would, in most cases agree. Bayesian reasoning is indeed a fantastic "road map for coming closer and closer to truth." However, contrary to Carroll's claims here, there are beliefs that are (to borrow a phrase from the presuppositionalist camp) preconditions of intelligibility. That is to say, there are beliefs and propositions that are necessary conditions for any sort of intelligible epistemology, and because of this it follows that such beliefs must be certain and cannot be "updated" or revised pending any new evidence (again, see below). One such proposition is the law of noncontradiction. This is a belief that we can be absolutely certain about, especially since any denial of it, even in principle, requires that it be true.

Poetic naturalism
I briefly expounded PN in the last post, yet there wasn't much space devoted to it. That's because the current section is where Carroll largely unpacks this epistemology.

[O]ur best approach to describing the universe is not a single, unified story but an interconnected series of models appropriate at different levels. Each model has a domain in which it is applicable, and the ideas that appear as essential parts of each story have every right to be thought of as "real." Our task is to assemble an interlocking set of descriptions, based on some fundamental ideas, that fit together to form a stable planet of belief. (p. 4) 

This brings us to the "poetic" part of poetic naturalism. While there is one world, there are many ways of talking about it. We refer to those ways as "models" or "theories" or "stories"; it doesn't matter. (p. 94) 

[S]omething is "real" if it plays an essential role in some particular story of reality that, as far as we can tell, provides an accurate description of the world within its domain of applicability. (p. 111)

 Again, on first glance there isn't much to quibble with here. It is true that certain models and theories regarding parts of reality, with their respective vocabularies, only need to be utilized in their respective domains of inquiry. Talking about free will and volition on the macroscopic scale of human experience utilizes a different model, and different vocabulary, than the models utilized when inquiring into the nature of atoms, electrons, and other subatomic particles.

However, the pertinent questions that need to be posed regarding this epistemology are the following: (1) Carroll places a lot of weight on models being "useful," and this utility being the litmus test for labeling something as "real," but what determines whether a specific model is useful, and why is utility important for our epistemology in the first place? Also, why should the fact that it is useful to describe reality using different models at different levels dictate what the actual nature of reality is, in principle?  (2) Are there other ways of talking about or modeling the world, besides PN?

Note that Carroll attempts to answer (almost) all of these questions. So, it's not as if he hasn't thought this through, and he probably wouldn't at all be fazed by any of them. However, that doesn't mean that his answers are convincing.

(1) is a question, or set of questions, that Carroll attempts to answer:

The question, however, is whether a particular way of talking about the world is useful. And usefulness is always relative to some purpose [...] "useful" means "providing an accurate model of some aspect of reality." (p. 143)

It is important that our models are accurate representations of some aspect of reality, however, this is not the traditional meaning of usefulness. Something is not useful if it accurately reflects a part of reality, rather something is useful if it can serve a practical purpose. Now, it is true that models that accurately reflect reality tend to be more useful than models that do not, but this doesn't mean that the latter is defined in terms of the former. This might seem like a minor quibble, but one problem with Carroll's PN is that throughout the section he constantly equivocates between both of these definitions. Sometimes "useful" is used as "serving a practical purpose" and other times it's used as "provides an accurate model of a part of reality."

What's the problem though (as if equivocation is not bad enough)? The problem is that the two definitions utilized by Carroll are sometimes mutually exclusive -- that is, there are times when a "model" or "story" can be useful even though it fails to accurately reflect reality. Carroll actually demonstrates such with his own example: he highlights the phenomena of transgender individuals -- people whose gender identity is different than the gender they were assigned at birth. Carroll says that if someone born male identifies as a female, then if this identification is "useful and meaningful" (p. 142) then why not identify them as a female? The problem here is that no matter how "useful" it is to identify someone as a female, this doesn't entail the fact that they are, in reality, a female.

Carroll doesn't see this as problem since he believes that classifications like male, female, and even human, are "human inventions." (p. 142) He claims these categorizations are not illusions because they are useful and meaningful in the contexts that we apply them. But again, something being useful does not necessitate that it accurately reflects an aspect of reality, and therefore it is possible that something be useful, yet be illusory.

And even worse for Carroll, the claim that a classification like "human" is a human invention is actually self-defeating. For to say that something is a cognitive construct of the human mind, one needs a nature of  "humanity" to objectively obtain. That is to say, for one to assert that something is a human invention necessitates that "human" be an objective referent, and not just a construct. So the proposition that the concept human is a human invention literally contradicts itself.

While Carroll doesn't comment on question (2) directly, he does make the following comment:

Poetic naturalism is at least consistent with its own standards: it tries to provide the most useful way of talking about the world we have. (p. 112)

Carroll is correct that PN is prima facie consistent with itself, but what about when we delve a bit deeper and consider the implications of question (2)? That is, is PN the only, or even the most useful, model, or story, of reality?  Well, surely it's not the only model of reality: there are a multitude of different ontologies. Ok. So then how do we determine which model is most useful? Well again, it depends on how Carroll is using the word useful.

If by "useful" Carroll means "serves a practical purpose," then it's not clear that PN is the most useful way of talking about the world. Moreover, how, on PN, do we even determine the most useful, or practical, way of talking about reality? It seems that we would need some idea regarding the fundamental nature of reality to be able to say model X is more useful than model Y. But then, is this "idea" about the fundamental nature of reality itself merely another "story" or "way of talking about the world" on some narrow domain? If so, then we're right back to the problem at hand wherein we need to determine how we know that this "model" or idea is "useful." What this means is that you can't have an ontology founded on nothing but "stories" and "ways of talking about the world." At some point you need a concrete ontology that describes how nature objectively operates, and this entails that you can't have an ontology that is purely "poetic", as Carroll uses the term here.

Moreover, if by "useful" Carroll instead means "providing an accurate model of some aspect of reality," then we run into the same problems. For, again, in order to know that a model is an accurate model of reality, we need to know something objective about the behavior and nature of reality that is not just another "way of talking about it" -- otherwise we go round and round in a circle again.

Emergence
Carroll then promulgates an emergentist ontology to make sense of different models of the world at different levels:

One pivotal word enables [the] reconciliation between all the different stories: emergence [...] A property of a system is "emergent" if it is not part of a detailed "fundamental" description of the system, but it becomes useful or even inevitable when we look at the system more broadly. (p. 94)

I do agree with Carroll that there are "emergent" phenomena. There are many such examples one could give of such phenomena, and Carroll gives a good explication using his own examples. But how does emergentism help PN? Carroll explains:

[E]mergence is about different theories speaking different languages, but offering compatible descriptions of the same underlying phenomena in their respective domain of applicability. (p. 100)

So emergence is a way to continue talking about the world at different levels, wherein the higher levels usually "emerge" from the lower levels.  This is all well and good, and so far I have no bone to pick with Carroll here, in principle. Where I might begin to disagree is if Carroll, later on in the book, tries to explain away something like consciousness as merely a "model" or "way of talking about" human experience that only applies at higher levels. (I haven't read the whole book yet, so if he does argue this then we can cross that bridge when we get there. )

Rationalism vs. empiricism
Since Carroll's epistemology is heavy on science and Bayesian reasoning, it should come as no surprise that he advocates a form of empiricism. That is, he believes that we can only know things about reality by looking at it and observing it. He contrasts this with rationalism wherein it is believed that knowledge comes intuitively without any need for empirical observation.

Carroll surveys the case usually given in justification of rationalism wherein the proponents appeal to the domains of mathematics and logic. Carroll argues against such an appeal by claiming that in both math and logic we simply derive consequences from differing axioms. This is, in a sense, correct, at least for math. For example, Euclidean consequences follow from Euclidean axioms, and non-Euclidean consequences follow from non-Euclidean axioms. But we need to actually look at the world to be able to determine whether it can be described by Euclidean or non-Euclidean geometry. No problem there.

However, there are those, like myself, who claim that there are axioms and necessary truths that must hold in any possible world at all. One example of this, as was already mentioned above, is the law of noncontradiction. This is not an axiom that might only hold in certain worlds, but might possibly fail to hold in others -- as in the case of Euclidean geometry. Rather, it is a necessary feature of having any kind of a reality at all. There is no axiom of non-contradiction and axiom of non-noncontradiction; there is only the former.

There are other propositions that are also claimed to be axiomatic and necessary -- e.g. law of identity, PSR, principle of causality etc. -- but I need not defend them presently. The point is that there are indeed things that we can know a priori, that is, without having to actually look at the world to justify them.

Carroll considers this point (briefly), and claims the following:

If we were thinking deductively, like a mathematician or logician, we would say that no collection of particular facts suffices to derive a general principle, since the very next fact might contradict the principle. (p. 135)

This seems to be quite absurd. For according to Carroll's reasoning, for instance, we cannot say the law of identity is an immutable principle, because we might one day come across something which is not identical to itself. This seems silly, and it should, because we already know intuitively that identity is a precondition of intelligibility of any thing that will ever exist. And so it goes with all other necessary truths. Now, there may not be many necessary truths with which we can know a priori, but there are a few, and they are a very crucial aspect of one's metaphysic.

All of this is important because it goes against Carroll's PN, as well as his form of empiricism. For if there are propositions that are necessary truths, then these truths aren't merely "models", "stories", or "ways of talking about reality." Rather, they are immutable principles that hold throughout any domain and any level, and cannot be shoved aside by the thought that one day we could discover them false. This is like saying that one day we might find someone who is successfully married and a bachelor.

Part III

A review of Sean Carroll's The Big Picture: Part I

Physicist Sean Carroll's new book The Big Picture: On the Origins of Life, Meaning, and the Universe Itself was released this past Tuesday (yay!). I, as well as many others, have been greatly anticipating the release of this book ever since Carroll announced it himself, and it's a pleasure to finally have it in my possession, and to be reviewing it.

I pretty much figured, before the book was released, that I would take up the task of writing a review. I felt this way because Carroll is an extremely articulate and modest philosophical naturalist and has been securing more of a secular following as of late--especially since he debated William Lane Craig, and, in my opinion, won--and I was very curious as to how he would make a cumulative case for a coherent naturalist metaphysic. And after beginning to read the book I do in fact feel that there are many things to comment on, as I had hoped. Though I obviously disagree with Carroll on many of his positions, Carroll's humble and unboastful attitude coupled with his articulate writing make this a great read.

So, on with the review, then. Carroll's book is split into six sections: Cosmos, Understanding, Essence, Complexity, Thinking, and Caring. I am, so far, planning to write a review on each section individually, though it might be the case that I don't have many comments to make on a particular section, and thus I might not review all of them. This Part I review will focus on the section labeled Cosmos.

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 Carroll begins the book by asking some important questions about the fundamental nature of reality, and stressing the importance of thinking about ontology. It is among this discussion of ontology that he begins advocating for philosophical naturalism. But Carroll's naturalism does not merely claim that all that exists is the natural world exhibiting patterns. Rather, Carroll introduces what he calls poetic naturalism. The "poetic" aspect of poetic naturalism (PN) is constituted by how we talk about, model, and interpret reality. Carroll describes this view:

[O]ur best approach to describing the universe is not a single, unified story but an interconnected series of models appropriate at different levels. Each model has a domain in which it is applicable, and the ideas that appear as essential parts of each story have every right to be thought of as "real." Our task is to assemble an interlocking set of descriptions, based on some fundamental ideas, that fit together to form a stable planet of belief. (p. 4)

This explication of poetic naturalism is very similar to two theories I've surveyed in the past, namely Model-Dependent Realism, as promulgated by Hawking, and Embodied realism, as promulgated by Lakoff. The key aspects of this philosophy are that we, as humans, talk about and describe different aspects or "levels" of the world using different models and different vocabularies, and that, as long as these models are consistent and coherent, they can overlap and reconcile with one another.

Unfortunately, Carroll doesn't delve too deep into this philosophy in the first section. Rather, he spends more space expounding this perspective in his second section Understanding--which should make sense since the "poetic" aspect of this philosophy is mostly epistemic. Therefore, I will save my comments on poetic naturalism until the next installment of the review.

Causality
One way that Carroll attempts to demonstrate the "layered" models of reality we conceptualize, as predicated by PN, is with Aristotle's notions of natures and causes. For Aristotle famously promulgated the principle of causality, which stated that something can only be "moved" if it was caused to do so by something else in motion. (Of course, by "motion" Aristotle really meant change, and by change he really meant something which is being reduced from potency to act.) But Carroll claims that the conservation of momentum has relegated such notions to mere useful macroscopic descriptions and constructions:

[T]he whole structure of Aristotle's argument for an unmoved mover rests on his idea that motions require causes. Once we know about conservation of momentum, that idea loses its steam. [...] What matters is that the new physics of Galileo and his friends implied an entirely new ontology, a deep shift in how we thought about the nature of reality. "Causes" didn't have the central role that they once did. The universe doesn't need a push; it can just keep going. [...] Of course, even today, we talk about causes and effects all the time. But if you open the contemporary equivalent of Aristotle's Physics--a textbook on quantum field theory, for example--words like that are nowhere to be found. We, still, with good reason, talk about causes in everyday speech, but they're no longer part of our best fundamental ontology. (p. 28-29)

I have a couple comments at this point. First, the conservation of momentum--which is embedded in Newton's law of inertia--doesn't, at all, call Aristotle's idea of motion into question. For, again, Aristotle said that when something changed, this required something responsible for that change. But uniform inertial motion is seen, as explicated by physicists, as a state in itself, and not a change per se. That is, the state of motion of an object is its velocity, and thus an object with a uniform state of motion is an object that is moving at a constant velocity--as long as it is not being acted upon by an unbalanced force--and thus is not changing, according to physics. Therefore, the conservation of momentum does not at all run counter to Aristotle's metaphysical principle, in fact, it is completely irrelevant to the principle.

Second, it is simply not true that talk of causality, at least efficient causality, is absent from contemporary scientific textbooks. In fact, it's ironic that Carroll specifically mentions quantum field theory textbooks since in An Introduction to Quantum Field Theory the authors write the following: The necessity of having a multiparticle theory also arises in a less obvious way, from considerations of causality[...] In a relativistic theory, this conclusion would signal a violation of causality. (p. 14)

These points may seem peripheral, but I believe they are important for a couple of reasons. First, the unmoved mover argument of Aristotle, if valid, would defeat a naturalist ontology, which Carroll holds. Yet, Carroll quickly dismisses Aristotle's unmoved mover argument, in light of the supposed irrelevance of concepts of causality, yet he does so fallaciously. Again, this isn't that big a deal since Carroll's thesis is not predicated on discussing Aristotle's proofs for God. Nevertheless, his fallaciously swift dismissal of the efficacy of causality is still a strike against his case.

Second, Carroll is trying to score a point for poetic naturalism by claiming that the language of causality is only a folk theory constructed from interactions at the macroscopic level, and isn't part of our "fundamental ontology" and has no utility in the domain of physics. Yet the fact that this has been demonstrated to be false with the quote above (one of many) already begins to poke holes in Carroll's form of naturalism. That is, we see that a concept like causality is not simply a model that only applies in one limited domain. Rather, it in itself should be part of one's fundamental ontology.

Carroll also makes much of the fact that causality is nowhere to be found in the laws of physics, and claims that such concepts are "emergent":

We look at the world around us and describe it in terms of causes and effects, reasons why, purposes and goals. None of those concepts exists as part of the fundamental furniture of reality at its deepest. They emerge as we zoom out from the microscopic level to the level of the everyday. (p. 54)

This is not correct, though. While it is true that causality is not palpable in the mathematical equations of physics and quantum physics--though we shouldn't expect it to be, since causality is not quantitative--this does not mean that causality is not operative and efficacious as it pertains to "reality at its deepest." I maintain that causality is ubiquitous at every turn, in the microscopic and macroscopic levels of reality.

To see this, consider the famous experiment conducted by physicist Hendrick Casimir in 1948. Casimir placed two metal plates one ten-thousandth of a centimeter apart in a quantum vacuum. As one might logically theorize, these plates would stay put, since the space is empty and thus there are no forces to affect the plates. But they didn't stay put, rather they were driven towards each other! And the first question that should come to one's mind is "Well, what was the cause of this effect?" It turns out that the cause is that there is an imbalance between the quantum fluctuations in between and outside the plates, and this imbalance yields a pressure imbalance, which pushes the plates together.

The point here is that, contra Carroll, causality is no less efficacious in a quantum vacuum than in our familiar everyday lives, and causality does simply emerge as we "zoom out" from the microscopic to the macroscopic.

Reasons Why
Carroll also spends a good amount of the first section discussing our constant search for "reasons why" things happen or why facts obtain. He agrees that the search for explanations is extremely rational and makes sense in our everyday lives. Where Carroll draws the line is when one makes this search for explanation a metaphysical principle (e.g. the Principle of Sufficient Reason) that pronounces that everything must admit of explanation, or a "reason why." This is, no doubt, a very modest and logical position to take. Carroll is not committing one way or another to whether all things and facts admit of explanation. He humbly claims that they might or might not, and leaves the door open to the possibility of brute facts.

However, as one who does in fact believe that all things and facts must necessarily and logically admit of explanation, I do not agree with Carroll here. And I find that his arguments against the PSR to be rather weak. Carroll claims that "[o]ur standards for promoting a commonsensical observation to a 'metaphysical principle' should be very high indeed. "(p. 41) Now, I would agree here, but Carroll really doesn't survey any concrete arguments actually given (besides Leibniz's Principle of the Best) that would attempt to demonstrate why the PSR should be taken as a metaphysical principle. He merely says the following:

[F]or every fact we notice about the universe: as soon as we apprehend it, we think there must be a reason behind it. This isn't an argument that the Principle of Sufficient Reason is logically incontrovertible; it only implies that we often act as if something like it were true. If we're honest, it's an empirical, evidence-based argument, not an a priori one. (p. 42)

I agree with Carroll that this argument he has articulated is not a priori, and is not logically incontrovertible. The problem is that no (logical) person attempting to establish the PSR as a metaphysical principle would use this argument, especially since it's just an inductive argument which cannot form an immutable principle at all.

The type of arguments that are given in favor of the PSR (and that are a priori) consider the nature of epistemic chains of explanation themselves. And they argue that explanation forms an instrumental and transitive chain, so that if even one member of a chain is unexplained (i.e. is a brute fact) then the chain as a whole loses efficacy. (Indeed, I have argued that very thing here, though I don't expect Carroll to have read my own specific post.) The point is that Carroll has not done the appropriate philosophical leg-work to dismiss the PSR as casually as he has done. And again this is important because the PSR puts a wrench in the works of his poetic naturalism, and also calls into question many other pronouncements he makes in the book, as we'll see in subsequent reviews.

The arrow of time
More importantly, in Carroll's eyes, the denial of the immutability of causality and explanation, as well as the displacement  of their existence as a mere human convention of utility, is ultimately illuminated by the increase in entropy and the arrow of time:

"Memories" and "causes" aren't pieces of our fundamental ontology describing our world that we discover through careful research. They are concepts that we invent in order to provide useful descriptions of the macroscopic world. The arrow of time plays a crucial role in how those contexts relate to the underlying time-symmetric laws of physics. (p. 66)

Carroll's point is that we only utilize concepts like causality and explanation because events progress from past to future, due to the arrow of time. This is to say that such concepts are contingent upon the direction of time, which is itself a contingent fact of the universe and could have been otherwise. But the laws of physics, on the other hand, do not have an arrow of time imprinted into them, and thus, as Carroll claims, concepts like causality and explanation are not carving reality at its joints, but are only concepts that humans constructed in order to make sense of the world as we interpret it. For had the arrow of time been in the opposite direction, things would be very different, as would our concepts and models.

Now, while it is true that if the arrow of time were pointing in the reverse direction, from future to past, events in the world would unfold in a completely counterintuitive and foreign manner, this would still not remove the necessity for concepts like causality and explanation. For explanation and causality are always present wherever things exist and behave, and wherever events and processes occur. And even in a universe where the arrow of time were reversed, you would still have things which exist and events which transpire; and as long as you have that, you have causes and effects, as well as explanations.

So I maintain that Carroll has not demonstrated how humans "invent" these concepts, and again,  this is important, because Carroll's poetic naturalism in founded on the idea that these concepts are human constructs and models, invented through our interaction with the world on the macroscopic level due to utility. However, if these concepts are not cognitive constructs but are immutable principles embedded in the fabric of reality, then Carroll's form of naturalism loses ground.

Part II

Sean Carroll and teleology

I’m quite excited for physicist Sean Carroll’s new book The Big Picture. It seems like a serious and erudite case for a comprehensive naturalistic worldview. In fact, I’m quite fond of Carroll, I find him to be one of the most articulate, intriguing, and respectable popular naturalists today. If more dialogue between theism and atheism took place with the demeanor that Carroll carries himself with, I truly believe that some progress would be made in these discussions. Carroll is one whom all theists should listen to, even if they disagree with him.

In any event, I was perusing his blog Preposterous Universe the other day and came across his post on “dysteleological physicalism.” Carroll’s defense of this ontology is, first, predicated on the idea that it is the job of physics to tell us what exists—you’ll remember Carroll echoing this sentiment in his debate with Craig wherein he claimed that our metaphysics must follow our physics—and thus everything that exists is physical; second, Carroll’s position rests on the notion that things that exist have no objective purpose or goal, and therefore have no teleology.

It’s no secret, among the common readers of this blog, that I disagree with both of these sub-ontologies that make up Carroll’s brand of physicalism. I think that the ontology of the universe is obviously not all that physics tells us, and I believe that teleology is intrinsic to the universe in the form of final causality. It is the latter belief that I plan to survey presently.

Carroll begins commenting on teleology with a very pertinent question, and continues from there:

If the world is made of things, why do they act the way they do? A plausible answer to this question, elaborated by Aristotle and part of many people’s intuitive picture of how things work, is that these things want to be a certain way. they [sic] have a goal, or at least a natural state of being. Water wants to run downhill; fire wants to rise to the sky. Humans exist to be rational, or caring, or to glorify God; marriages are meant to be between a man and a woman.

This teleological, goal-driven, view of the world is reasonable on its face, but unsupported by science.

The question of why things act the way they do should be near the forefront of one’s ontology. While physics can say that X behaves in such a way, it doesn’t (and cannot) answer the question of why it behaves that way in the first place. And so, to Aristotle, the notion of final causality was one concept that aided in answering this question. He claimed that we see certain effects uniformly follow from certain causes, under certain conditions, because the cause was aimed at producing said effect. (Note that while some of Aristotle’s examples that he utilized were physically wrong, this doesn’t negate the ontology of the concepts.)

However, Carroll remarks that this teleology is not supported by science, not just in the sense that science makes no use of teleology, but in the sense that science has actually “undermined” it. He goes on to say the following: At a basic level, all any object ever does is obey rules — the laws of physics. Thus, for Carroll, the “reason” that an object is in state Y can be fully explained by the fact that the object was previously in state X, and, by the laws of physics, state Y is a succession of state X. No purpose, no goal, just physics.

I maintain that this is false, and that Carroll has only side-stepped the issue by committing a category mistake. Nobody questions that because of the laws of physics we can explain how state Y was obtained from state X. That’s all well and good. The question is why state Y always succeeds state X. Why are certain effects generated from certain causes? Why is there causal regularity at all? Carroll’s attempt to run to the laws of physics for help doesn’t work here, for the laws of physics only redescribe the behavior of matter, and the behavior of matter is what we’re looking for explanation for in the first place!

(As a side note, this is a problem I see committed in education all the time, especially in math and science. A student asks why a certain property or rule holds—like, for instance, why acceleration is the derivative of velocity—and instead of answering the question the teacher just says, “because when we take the derivative of velocity, we arrive at acceleration.” But this obviously is not an answer to the “why” question. The teacher who does this is merely redescribing the property, instead of illuminating why the property is even efficacious in the first place. )

So Carroll’s trust in the laws of physics to relinquish teleology is misplaced. But it’s even worse than this: it’s false. For as I’ve argued before, the laws of physics supervene on causally regulated matter. That is to say, the laws of physics are contingent on uniformly behaving matter, and thus cannot possibly be that which explains why it behaves that way. So, what can explain this behavior? Well, if causal regularity exists in nature—if A’s regularly produce B’s, under certain conditions—then this can only be because A has an inherent dispositional tendency to bring about B. For instance, an acorn yields an oak tree, not because the laws of physics say it will, but because the acorn has an intrinsic disposition in it as a substance that is directed towards the generation of an oak tree. Recall that if this were not the case—that is, if substances did not have these dispositions—then one effect would not follow more frequently from any substance.

This concept of a substance harboring a tendency (sometimes called a “power”) to generate a specific effect is what is known among Aristotelians as final causality. And yet many philosophers, with no Aristotelian axe to grind, have returned to this ontology under the name of Dispositionalism. Again, this ontology is seen as a necessary condition for causal regularity, and is not at all ad hoc. (Notice as well that final causality is not an attempt to replace the laws of physics, rather it is only an explanation given at a deeper metaphysical level that explains why matter can even behave regularly so as to even be describable by physical laws.)

Therefore, it seems that Carroll’s dysteleological physicalism—at least the dysteleological part—is false. Carroll’s appeal to laws of physics can only be valid if there is causal regularity, and causal regularity is valid if and only if substances have final causality—that is, a goal or end that each substance is disposed towards generating—which is teleological. Carroll’s statement that “all any object ever does is obey rules” can only be true if teleology is inherent in matter. Thus, Carroll’s position actually supervenes on a teleological ontology and therefore cannot in any true sense be dysteleological.

Why something rather than nothing? Part II

Let us continue our survey regarding naturalist answers to the existential question of why something exists as opposed to nothing. We will now turn our attention to esteemed physicist Sean Carroll. Carroll’s answers will be pulled from two articles he’s written (here and here) —one written as a direct answer, and the other only written as an answer indirectly--over at his blog Preposterous Universe.

 Carroll articulates his answer:

First, we would only even consider this an interesting question if there were some reasonable argument in favor of nothingness over existence.[…] Ultimately, the problem is that the question — “Why is there something rather than nothing?” — doesn’t make any sense. What kind of answer could possibly count as satisfying? What could a claim like “The most natural universe is one that doesn’t exist” possibly mean? As often happens, we are led astray by imagining that we can apply the kinds of language we use in talking about contingent pieces of the world around us to the universe as a whole. It makes sense to ask why this blog exists, rather than some other blog; but there is no external vantage point from which we can compare the relatively likelihood of different modes of existence for the universe. So the universe exists, and we know of no good reason to be surprised by that fact.

Carroll also states the following related remarks:

[T]hat’s just how things are. There is a chain of explanations concerning things that happen in the universe, which ultimately reaches to the fundamental laws of nature and stops.

The question—“Why there is something rather than nothing?”—other than: something (the universe) exists, because it just does. There is no reason why it does, since reasons are only pragmatic inside the universe, and applying them to the universe itself is superfluous.

Such modesty by Carroll is refreshing but, alas, his answers are not only unsatisfying, they are fallacious. First of all, Carroll completely misinterprets exactly what the existential question is getting at. The question is not interesting only if there were an argument in favor of nothingness. The question is interesting because the universe seems to be contingent—a point that Carroll will later admit, interestingly enough—and contingent things require something else that explains their existence. So the question is really asking “What is it that keeps the universe from being nothing at all?”

 Now Carroll’s answer is obviously unsatisfying because it amounts to saying nothing at all—e.g., “That’s just how things are.” Analogously, imagine my Calculus students asking me why the definition of a derivative involves a limit, and I answered, “there’s no reason, it just does.”  Obviously this is no answer at all, and this is tantamount to Carroll’s answer. But Carroll knows this, and further justifies his argument by claiming that the type of existential explanations we’re looking for here will only lead us to a dead end--because such explanations cannot be applied to the universe itself, since the universe “[is] not embedded in a bigger structure; it’s all there is.” So, since the universe is “all there is”, there is no framework whereby we can expect an explanation for the existence of it.

 Good answer, right? Wrong. There’s a few problems. First, Carroll is blatantly begging the question here by claiming the universe is all there is. It is not clear that the universe is all there is, and Carroll would first have to demonstrate such a proposition before he used it as an out in this discussion. It might very well be the case that there is an ontologically higher realm than the universe of which the universe participates in an explanatory chain. Thus stated, inherent in Carroll’s answer is a blatant unsubstantiated assumption of naturalism.

 Second, even if the universe were the whole shebang, this does not mean it cannot have an explanation. That is to say, the universe could be self-explanatory. You see, an explanatory chain must end somewhere, and it can only end in something that is self-explanatory, otherwise the explanations, along with the chain, continue. So Carroll is actually incorrect that our inquiry into explanations must stop with the universe itself which has no explanation. For the universe could indeed be self-explanatory, and therefore provide a much satisfying answer to our existential quandary.

 But even Carroll concedes, indirectly, that this is not the case, that is, that the universe is contingent, and therefore not self-explanatory:

[One possible reason why the universe is the way it is] is logical necessity: the laws of physics take the form they do because no other form is possible. But that can’t be right; it’s easy to think of other possible forms. The universe could be a gas of hard spheres interacting under the rules of Newtonian mechanics, or it could be a cellular automaton, or it could be a single point.

What’s crucial here is that Carroll is admitting the universe did not have to be this way—this way being the way the universe has actually been configured. But, that means that there must be a reason why the universe is this way as opposed to another possible way. Which means that the universe is contingent, since this is literally one of the definitions of contingency. But if something is contingent, then it cannot be self-explanatory, since the reason for its existence is not sought within itself.

 Thus stated, we see that Carroll’s attempt to relieve the universe of explanation has failed. He has not answered the existential question, and even where he has tried, he has only put the case for naturalism in jeopardy.