Friday, May 12, 2017

Contra Scott Clifton on the Principle of Causality

It’s been quite a while since I last posted an article on my blog; in fact, I pretty much told myself I was done blogging. And yet here I am…blogging again – “Just when I thought I was out, they pull me back in.” But, instead of explaining my absence, or promising that I will blog in the future, I think I’ll just jump right into my post.

I’ve looked up to Scott Clifton (also known on YouTube as Theoretical Bullshit) for a long time now, ever since I first watched him in my favorite soap opera The Bold and the Beautiful. Ok not really, I’ve never watched him in a soap opera. I really looked up to him because of his videos on YouTube. I began watching Scott’s videos around 2010, when I was still a naive Christian apologist, and even though I disagreed with him more often than I agreed—though now that’s changed—I always took him very seriously intellectually, and I still do—in fact, his argument from nonbelief has helped shape my present beliefs.

Recently, to my pleasant surprise, I discovered that Scott has a blog on his website, and already has a lot of great articles. And it’s one article in particular that I have felt the need to address: an article entitled Beginning to Exist: A Critique of Kalam’s First Premise—please make sure and read Scott’s article before following along with my critique. Now, hopefully my readers (however many of them are left) know that I am not a William Lane Craig fan, in fact I disagree with him on virtually everything—and I certainly am not a fan of the Kalam Cosmological Argument (KCA). However, I do in fact endorse the first premise of the KCA, and I do believe it to be true, and thus I disagree with Scott in this regard. Hence my motivation is manifest for the writing of this post.

So, before we jump into Scott’s criticism, I believe most of my readers are aware of the first premise of the KCA: (P1) everything which begins to exist has a cause. This is a basic form of the principle of causality (which I have defended here) and, obviously, in order for the KCA to be sound, this premise needs to be true. This is where WLC attempts to justify said premise, and Scott lists Craig’s justifications as follows:
         1)   Something cannot come from nothing. 
               2)   If something can come into being from nothing, it becomes inexplicable why just anything                   or everything doesn’t come into being from nothing.
               3)    Common experience and scientific evidence confirm the truth of [P1].

Scott then begins with his criticism of (1):
It’s odd that Craig ever refers to this [sic] an “argument”. It’s not an argument; it’s a claim. And why should I, his intended audience, believe this claim? Craig’s answer is that this is a “metaphysical intuition” we all share. But what is an intuition? As an evolved primate whose cognitive abilities were naturally selected for survival and mating, why should I—an atheist for whom the Kalam Cosmological Argument is intended—take this seriously as an epistemic tool for determining the ultimate metaphysical nature of reality? What should I understand my intuitions to be, exactly, if they are not ultimately reducible to induction? How could this “metaphysical intuition” (which I don’t share, by the way) be anything other than an inference—conscious or subconscious—derived from my empirical knowledge of temporal, spatial, ex materia causality in the physical world? Isn’t (1) really just (3) in ‘metaphysical clothing’?
There’s a lot to unpack here. First, I agree that if one of Craig’s arguments for (P1) is simply to assert (1) as a mere intuition, then he has much work ahead of him. That being said, I don’t share Scott’s skepticism towards this principle, for reasons I will explicate shortly. Now, while I do agree that principles like (1) are abstracted from the spatiotemporal world, I don’t see that this hinders one from pronouncing (1) as a necessary proposition that we can be certain of.

Take, for instance, the cornerstone of logic and epistemology, the laws of logic. As I’ve argued in the past, we can be absolutely certain of these principles. Is P identical to P? Certainly. Is it the case that an existent cannot be both P and not-P  at the same time and in the same respect? Absolutely, etc. etc. Again, these logical laws are seen to be (by most logicians) logically necessary truths which would hold in any conceivable world—spatiotemporal or not—and it certainly is not a problem that these principles are abstracted from the world we observe. Now, is Scott skeptical of the efficacy of the laws of logic the same way he’s skeptical of (1)? I can’t say. But, if he is then I fail to see how this wouldn’t poke major holes in his epistemology.

More to the point, all that would need to be demonstrated in order to equate the efficacy of (1) with the efficacy of the laws of logic is to demonstrate that the former, like the latter, is a necessary truth. And this is not difficult to argue—though, in order to be as exhaustive as I can to argue this point, I will be using more Aristotelian-Thomistic jargon than analytical jargon [insert eye-roll here].

The phrase “something coming from” indicates that at one time this “something”, or whatever made up this “something”, only had the potential to do this, and thus when it did in fact come from whatever it came from, it was reduced from potency to act. Just like in order for water to come from ice, the ice had to, at some point, have only had the potential to become water, and subsequently when it did become water, this potency became actual.

Furthermore, “nothing” in A-T terms just means non-actual. But, non-actuality cannot move something from potency to act because you need something actual to reduce something from potency to act in the first place, like a lighter in the case of the ice—note that the mere potency cannot move itself since potency is only potential, not actual. Since that which is non-actual literally cannot do anything, it therefore cannot possibly be that which reduces the existent from potency to act. Therefore, there is no possible world in which something can be reduced from potency to act by something not already in act. Thus, there is no possible world in which something can come from nothing, which is the very definition of what makes something a necessary truth. 

Along with claiming that (1) is not a metaphysical principle we can be certain of, Scott maintains that there are other linguistic problems with this principle:
Further, there’s some very tricky language being employed here, and it causes other problems. Ask yourself if (1) is logically equivalent to:  
          (1′) Something cannot not come from anything.
Well if “nothing” means “not-anything”, then yes, the two statements (1) and (1′) are indeed logically equivalent. However, this presents a problem, since God by definition “didn’t come from anything”. So if God exists, then this proposition is false, and vice versa. Meaning the (logically equivalent) proposition, “Something cannot come from nothing” is also false, or else theism is false.
This seems to me to be blatantly false. (1) is not logically equivalent to (1’) and we can prove such simply by explicating the corollaries of logical equivalence. One corollary of two statements being logically equivalent is that the relation of consequence holds in both directions between them, which, in other words, means that the two statements are necessary and sufficient conditions of one another. So, let’s demonstrate that (1) and (1’) are not logically equivalent by demonstrating that one is either not sufficient or necessary for the other, and this is easier to see if strip the statements of particulars and restate (1) and (1’) as follows:

           P: X cannot come from Y
           Q: X cannot not come from not-Y.

Now, consider the following conditional statements:

          (C1): If P, then Q.
          (C2): If Q, then P.

When put in this form it should be clear (based on C1) that P is not a necessary condition for Q to obtain. Likewise, based on C2, Q is neither a sufficient nor necessary condition for P. Thus, P and Q, and therefore (1) and (1’), cannot be logically equivalent, contra Scott’s claim.

Not so fast though because Scott anticipates this objection:
“Perhaps [Craig] would grant that the terms “nothing” and “not-anything” are logically equivalent, but reject that the two statements (1 and 1′) are logically equivalent. He might say—and I’m just spitballing, here—that the true logically equivalent proposition to (1) would be:   
           (1″) Something cannot come from not-anything.
Meaning we must turn our focus to the phrase “come from”. God, you may argue, didn’t “come from” anything at all, whereas an uncaused universe would have “come from” not-anything, and that’s the difference. But is that even coherent, let alone true? I think not! Why think the phrase “came from” applies to the universe any more than it applies to God? If the earliest moment of the universe was the first moment of time itself, it is incoherent to speak as if the universe did any “coming from” at all. It would simply be the case that the universe exists at all points in time, and that there exists no moment prior to its existence… just like God.”
First, Scott asks a pertinent question here, namely, why suppose that the phrase “come from” applies to the universe any more than it applies to God? The answer is that the universe is not necessary, whereas God, if he exists, would indeed be necessary. And if the universe is not necessary, then either it has a cause or it’s a brute fact—I’ve argued against the latter here. And if the universe has a cause, then this opens the door for the phrase “coming from” to at least have a possible metaphysical application to the universe, whereas God would not have this possibility.

Second, is it true that if the universe did not have a first moment, then it is incoherent to speak of it “coming from” anything? Indeed it seems to be, and I actually agree with Scott here; principle (1) would not apply to the universe, if it did not have a beginning, just like it wouldn’t apply to God. Thus, I agree with Scott when he says that, “(1) could be true yet have no implications for the universe.”

However, does this actually mean that the universe, therefore, didn’t have a cause? Not necessarily, for, as I’ve argued in the past (here), there are cases of efficient and material causation which are non-temporal. If this is correct, then the universe can still have a cause without temporally coming into existence, and therefore it would still be contingent. However, let us note that, in his post, Scott did not survey whether or not the universe is contingent because it is outside of the subject matter dealt with in said post, so he can’t be faulted for not considering these responses.

At this point Scott delves into Craig’s justification for (1) based on an A-theory of time, and at this point I have no hard opinions on what he articulates. Subsequently, Scott then addresses Craig’s second (2) and third (3) argument for (P1), yet, in agreement with Scott, I don’t find (2) or (3) very persuasive, so I have little to say here. However, let it be known that in his discussion of Craig’s arguments for (3), Scott makes many comments regarding the nature of temporal causality that I would not agree with, but I feel as if the comments I’ve made above, and the articles I’ve linked to regarding causality, suffice to provide an answer to said comments.

That being said, keep in mind that Scott has not dealt with (P1) directly in his article—though he has elsewhere—but only Craig’s arguments for said premise. So, in the end, we have an interesting mashup of arguments. Most of Craig’s arguments for (P1) were poor and unpersuasive, and yet Scott’s arguments against (1)—the only “argument” of Craig’s I find tenable—I likewise found to logically invalid and unpersuasive.

Monday, October 10, 2016

Why I went vegan, and why you should as well

I've eaten a standard Western American diet for all twenty-six years of my life. Eggs, dairy, meat? You betcha, all day every day. But a couple of months ago in mid July I decided to go vegan cold-turkey (no pun intended)--that is, no more eggs, dairy, or meat. My reasons for this life-altering decision will be articulated below, but let the reader be aware that this is not something I had ever considered--it's not something that I mulled over in my mind and went back and forth on. A vegan lifestyle was the furthest thing from my mind. In fact, the words "vegan" and "vegetarian" always elicited pejorative reactions from me. These lifestyles were always seen by me to to be less masculine and unnecessary. In fact, I bet many of you, upon reading the title, prematurely rolled your eyes and muttered something under your breath--I was that guy too. But, I was wrong.

So, why did I go vegan? Well, to be honest, I really just watched one documentary. That's it, just one. It wasn't Earthlings, though everyone should watch it. And it wasn't Forks over Knives, though everyone should watch it as well--if they care at all about their health. No, the documentary I watched was Cowspiracy, which, sorry to be redundant, you should definitely watch. I watched Cowspiracy and walked away a vegan, it's as simple as that.

Moreover, as I subsequently began to research more and more about veganism, it wasn't the statistics in Cowspiracy that kept me motivated and drew me towards a vegan diet, it was the health benefits. So now my main reason for being vegan is that I want to live as healthy a life as possible while simultaneously doing all I can to help the environment. And to be honest, nothing has been so easy. Despite what you might think, it is not hard to go vegan, and no, I don't at all miss meat, cheese, milk or eggs.

So, that's why I went vegan--nothing too interesting. The more pertinent question, though, is why you should go vegan.

Health, Wealth, and Prosperity
When I used to picture a vegan, antecedent to going vegan, I would picture a scrawny, wimpy, pale little weakling who was most likely nutrient deficient. That couldn't be farther from the truth. It turns out that a vegan lifestyle is the healthiest lifestyle for a human being. According to this study from the National Institutes of Health, which studied the nutritional quality of vegan, vegetarian, and different varieties of omnivorous diets, the results, "indicated consistently the vegan diet as the most healthy one."

Also, the demographics with the highest life expectancies (called blue zones) tend to be societies where meat and animal products are rarely consumed. For example, in 1949 the people of Okinawa, Japan--the historical demographic with one of the highest number of centenarians--ate virtually no meat. Their greatest consumption of meat was fish, yet their dietary intake of fish constituted only one percent of their overall dietary intake, and their overall consumption of animal products constituted less than four percent their total dietary intake (see here) [1].  Currently, the demographic with the highest life expectancy are the Adventist vegetarians in Loma Linda, California. Being vegetarians, they obviously don't consume meat and yet they have the greatest longevity of any demographic recorded to date.

So, if populations that eat little to no animal products have better health and longevity, does this imply that the more animal products you eat the less healthy you are? Well, that's what the data show.  Populations that eat a westernized diet tend to have more incidences of cancer and circulatory diseases, than those that don't.

But, why is this the case? Well, it's because many of the contents in animal products are carcinogenic, and the dietary cholesterol--only found in animal products--and trans fatty acids contribute to atherosclerosis--the number one killer in America. The latter should be uncontroversial, so let's survey the former.

Scientific studies have found many things that feed cancer, and many of these these are either found exclusively in animal products, or are found in the highest amount in said products.First, it was recently discovered that cancer cells feed off of cholesterol (see here and here). High LDL cholesterol levels are produced from high dietary cholesterol intake, which only comes from animal products--our bodies already produce all the cholesterol we need, and we actually have no need for dietary cholesterol. Second, cancer also feeds off of the amino acid methionine. This has actually been known since the 1970's. See, methionine is actually necessary for humans, but large quantities of methionine can actually feed cancer cells and help them metastasize. And what foods tend to have the highest levels of methionine? Animal products. Third, estrogen has been found to be carcinogenic, and has been linked to breast and prostate cancer. In fact, the American Cancer Society has labeled estrogen a type I carcinogen--which means it's known to cause cancer. Obviously, cow's milk contains incredible amount of estrogen, but it turns out that there's also excess estrogen in meat and eggs. [2] Fourth, high levels of a growth factor in our bodies called IGF-1 are also responsible, and necessary, for helping cancer metastasize and spread. And where can these dangerously high levels of IGF-1 come from? Well, not only is IGF-1 present in animal products, but consuming animal protein causes our liver to secrete a bunch of IGF-1(see here and here).

So the point here is that eating animal products makes you much, much more susceptible to cancer and other diseases. This is why the more plant-based a population's diet is the less their incidence of cancer and circulatory diseases. (Heck, even going vegan for only two weeks can significantly reduce and reverse cancer cell growth, see here.) And this is why this study states that, "vegan diets seem to confer lower risk for overall and female-specific cancer than other dietary patterns." Thus, it seems that if one desires to be healthy and flourish, then going vegan is the way to go.

Eating meat is destroying the environment
The other main reason that should persuade the rational individual to go vegan is regarding how animal agriculture is negatively affecting the environment. To list a few figures:

  • Animal agriculture is responsible for 18 percent of greenhouse gas emissions, which is more than the exhaust emissions from all human transportation combined, which is 13 percent (see here). 
  • Animal agriculture is responsible for at least 80 percent of US water consumption (see here). 
  • 2,500 gallons of water are needed to produce one pound of beef (see here, here and here). 
  • Animal agriculture is the leading cause of species extinction, ocean dead zones, water pollution, and habitat destruction (see here, here and here). 
  • A farm with 2,500 dairy cows generates as much waste as a city of 411,000 people (see here). 
  • We could see fishless oceans by 2048 due to overfishing (see here). 
  • For every pound of fish caught, up to five pounds of unintended marine species are caught and killed as by-kill (see here). 
  • Animal agriculture is responsible for up to 91 percent of rainforest deforestation (see here).
  • One to two acres of rainforest are cleared every second (see here).  
  • Each day a person who eats vegan saves 1,100 gallons of water, 45 pounds of grain, 30 square feet of forested land, the equivalent of 20 pounds of CO2, and one animals life (see here and here).
There are many other daunting statistics that could be listed here. The point is that eating meat and consuming animal products is literally destroying the environment we live in, and you can't call yourself an environmentalist and consume animal products at the same time. You can literally make an impact on the environment right now by going vegan.

"But, like, where do you get your protein, dude?"
When people think about vegans, or going vegan, usually their first thought centers around nutrient deficiencies, such as protein. However, it turns out that vegans and vegetarians have about the same amount of protein intake as omnivores. It's said that male adults (like myself, I think) only need around 60 grams of protein per day. Speaking from  experience, I get in about 110 grams of protein without even trying to. It's really not that hard--plant protein is everywhere--just ask vegan Torre Washington (left).

[1] In fact, since 1949 Okinawa has begun to eat more of a westernized diet--i.e. more animal products--and as a result their longevity has decreased and their circulatory diseases have increased.
[2] This might be one reason why, on average, vegan men have higher testosterone levels than omnivores.

Tuesday, July 26, 2016

A treatise on brute facts

Two years ago I wrote a post geared towards a refutation of the existence of brute facts and what this entailed for naturalism. Since this time I have engaged in many discussions with naturalists regarding this very topic, and as a result of those discussions I have (slightly) altered and polished my argument. And because of this I have, for a while now, wanted to write up another, more systematic, post which attempted to demonstrate the impossibility of brute facts. So, here goes.

The Stanford Encyclopedia of Philosophy defines a brute fact as synonymous with an unexplainable fact. [1] In the same vein, Wikipedia states, "a brute fact is a fact that has no explanation. More narrowly, brute facts may instead be defined as those facts which cannot be explained (as opposed to simply having no explanation). " Right away we see that we can distinguish between two types of brute facts--those in practice (extrinsic), and those in principle (intrinsic). An extrinsic brute fact is a fact that we currently do not have an explanation for. An example of this would be the origin of life. We believe that the fact of life's origination has an explanation, we simply do not know currently what that explanation is. On the other hand, an intrinsic brute fact is a fact that has no explanation, at all, in principle. Considering an intrinsic brute fact, it's not that we don't know the explanation for X, but that X doesn't have an explanation to be known in the first place.

Now, nobody disputes the existence of extrinsic brute facts; we all agree that there are things we don't know. The point of contention, and our domain of focus in our discussion of brute facts, is whether or not intrinsic brute facts actually exist or whether they are even possible. This is what is to be considered presently.

What should be noteworthy at this point is the notion of a brute fact is defined in terms of explanation. And, as we'll see below, the concept of explanation, and what it entails, is crucial in determining whether or not brute facts are possible. So, what constitutes an explanation? Well, the problem with defining this term is that an explanation can be given in many different domains and contexts. Take these different cases of explanations: the teacher explains the lesson; Susan explains what she meant; the nail explains why the tire is flat; the nonzero net force explains the change in velocity; the premises explain the conclusion etc. Notice that in each of these cases the presence of something--e.g. someone doing the explaining, an object, a force, an abstract concept or proposition--is the reason for, and clarifies, that which, in the absence of that something, would be unclear--the lesson, the meaning, the flat tire, the change in velocity, the conclusion.

The important concepts just utilized are reasons and intelligibility. When some fact is explained, there is a reason, account, or justification--which can be grounded in many things, from an object to an abstract proposition, as we saw above--which imparts some form of clarity and intelligibility to the thing that was heretofore unclear. Therefore, I maintain that the proper definition of "explanation" that should be utilized is "a reason whereby something is rendered intelligible." [2]

Now, from this definition is entailed a crucial inference: something being explained is not the same thing as something actually having an explanation. The former is an action, dependent on minds doing the explaining, while the latter is not. Return to a couple of my examples above--namely, the teacher explaining the lesson, and the premises explaining the conclusion. The teacher explaining the lesson is an example of something actually being explained, and we could call this a case of explanation in practice (extrinsic). The premises explaining the conclusion is an example of something, the conclusion, having an explanation while not necessarily being explained to anyone currently, and we could call this a case of explanation in principle (intrinsic). (Note at this point that there is an identical differentiation here between the different types of explanation and brute facts.)

Not only are intrinsic explanations not equivalent to extrinsic explanations, but the latter actually presuppose the former. Intrinsic explanations are a necessary condition for extrinsic explanations. That is to say, in order for one to be able to explain something, there has to be an objective explanation available in the first place. It is incoherent to claim that something was explained that had no explanation. The teacher cannot give reasons that render a lesson intelligible if the lesson doesn't have a reason for its intelligibility. This is important because many of my interlocutors have claimed that explanation should only be focused on explanation in practice, yet this is nonsense, since, to reiterate my point, explanation in practice presupposes harboring an explanation in principle.

Another concept that is embedded in the notion of explanation is that of intelligibility, and just like explanation and brute facts, it comes in practice and in principle. For something to actually be made intelligible in practice means that someone has actually comprehended it. For something to be intelligible in principle means that it's possible that it could be comprehended, even if it never actually is. For example, the mechanism of gravity was unintelligible in practice for many decades, even though it was always intelligible in principle--that is, there always was an account for the mechanism of gravity. And once again, just like explanation, intelligibility in principle is a necessary condition for intelligibility in practice. For in order for someone to comprehend X, it is a necessity that its possible that X be comprehended in the first place.

Now, since we're currently interested in intrinsic brute facts, and not extrinsic brute facts, this entails that we are likewise interested in the nature of intrinsic explanation and intrinsic intelligibility, and not extrinsic explanation and extrinsic intelligibility. For since we're attempting to determine whether facts can be unexplainable in principle, we need to examine the nature of explanation in principle and see if this is something that can be done away with whilst a fact remains intelligible in itself. We will not go the way of the PSR and merely dogmatically assert that all things must have an explanation, rather we need only delve deeper into the nature of explanation and infer its entailments.

To begin, let us consider an example, similar to the example I utilized in my original post, of explanation in principle. In physics acceleration represents the rate of change of velocity with respect to time. Now, if we are curious as to the explanation of acceleration in principle, we can find this in the concept of velocity, since acceleration is literally defined in terms of velocity. And if we go further and ask for the explanation of velocity, we find this in the concept of the rate of change of position. Therefore, acceleration is explained by velocity which is in turn explained by position. What this means is that acceleration is granted intelligibility by the concept of velocity, which is granted intelligibility by position, so on and so forth.

This entails something very important: acceleration is ultimately explained by position. In the specific explanatory chain that we are considering, all the concepts that lead up to position are only ultimately imparted their intelligibility by position itself. If position is dropped, then so are all the subsequent concepts--if position is rendered unintelligible, then so is acceleration.

All of this entails something else that's even more important: explanatory chains are essentially ordered series. An essentially ordered series is a series wherein each member derives whatever efficacy it has from higher members--unless it is the highest member--such that if a member is lost, all the lower members will also be lost. This obviously fits like a glove with the example of position and acceleration above.

In any event, the notion that should be highlighted here when speaking of essentially ordered series is that of derivation or of "being imparted". That is, when A explains B, this means, per our definitions, that B is rendered or imparted intelligibility by A, that B would be unintelligible were it not for A. To return to our example, acceleration would be unintelligible were it not for velocity and thus acceleration derives its intelligibility from velocity. But, again, this is the case for any subsequent members of an explanatory chain with regards to a specific member. That is to say, if A explains B which explains C which explains D, then D ultimately derives its intelligibility from A, and only proximately derives its intelligibility from B and C.

What this likewise entails is that if A does not impart intelligibility to B, then B does not impart any to C, and likewise for D. And this is where consideration of brute facts come in. For where would a brute fact fit in such a chain of explanation? Surely it cannot be the highest member of an explanatory chain, because since a brute fact has no explanation then, by definition, it has no reason whereby it is rendered intelligible, and thus it would be unintelligible. But a reason needs to be intelligible itself if it is to render something else intelligible. (Again, consider acceleration and velocity, the latter has to be intelligible if it is to impart any intelligibility to acceleration.) Therefore, A being intelligible is a necessary condition for A to be an explanation for any B. Logically, this means that if A is unintelligible then it cannot be an explanation for any subsequent fact B. Thus, a brute fact cannot be the first member in an explanatory chain, for it would not explain anything while being itself unexplained. [3]

However, while a brute fact might not be the highest member in an explanatory chain, is it possible that it be a member somewhere in the middle? That is, can we have a chain A, B, C, D...wherein C is a brute fact? I don't see how, since, to reiterate the above point, C would not be able to explain D, and C could not be subsequent to B since B would then have to explain C--otherwise C wouldn't be in the chain to begin with--which would contradict our original premise for the nature of C--namely, its having no explanation. What we see, then, is that there is no place in an explanatory chain for a brute fact,  and if there is no place in an explanatory chain for a brute fact then it would seem that brute facts are impossible.

In addition to dispelling the notion of brute facts participating in the nature of explanation, we can add another argument--call it the argument from intelligibility. The argument can be formulated as follows: If a member F of an explanatory chain M is intelligible, then no members antecedent to F in M can be brute facts. Why can we deduce this? Well, if F is intelligible then it has a reason whereby it is rendered intelligible--otherwise it wouldn't be part of an explanatory chain, since it wouldn't have an explanation. And since intelligibility is imparted down through the members of  explanatory chains, we can say that for F to be intelligible, every member of M must also be intelligible--otherwise intelligibility is not imparted at some point in the chain. But if every member is intelligible, then every member must have a reason whereby it is rendered intelligible--again, otherwise it wouldn't have an explanation. And this means that every member does in fact have an explanation and cannot be a brute fact. Based on this line of argumentation, we can reach an interesting conclusion: if a fact is intelligible, then it cannot in any sense be linked to a brute fact, and thus we cannot posit a brute fact from anything that exists.

Now, attentive readers may have noticed something that it seems I have forgotten: namely, that there can be multiple explanations for something, and that these multiple explanations can form multiple explanatory chains that are interconnected, and thus, it would seem, my account of explanation and explanatory chains is too simplistic. I do agree that something can have multiple explanations and that there can be multiple interconnected explanatory chains that stretch across different domains. However, I maintain there is nothing about multiple explanatory chains that changes the nature of an explanatory chain in itself--and thus there is nothing that calls my conclusions into question.

To illustrate this, consider a case of combustion, perhaps a candle that is lit. What is the explanation for this lit candle? Well, we can think of a couple. One explanation is the fact that somebody actually lit the candle, from. Another explanation is an oxidizing agent and a chemical reaction. These are both genuine explanations since they are both reasons wherein the lit candle is rendered intelligible. And here we also have two explanatory chains that converge on a single state of affairs. So, we have a situation where one explanatory chain (...A, B, C) converges with another chain (...X, Y, C) at the fact of C--the lit candle.

The question that should be considered presently is whether or not the existence of C changes the nature of explanation considered above. It's difficult to see how it would change everything we've considered, since we still have something (C) which derives its intelligibility from antecedent members, such that, in the absence of such members, it would be rendered unintelligible. The only "new" notions that need be introduced are partial intelligibility and partial explanations. For if C is missing one explanation, out of two, then it is only partially intelligible, and thus the explanation it has is only a partial explanation. But notice that none of this changes the nature of explanation itself. It is still the case that in order for C to be intelligible in any sense, it needs to have at least one reason whereby it derives its intelligibility--even if this is only a partial intelligibility. And, more importantly, the fact that C derives its intelligibility from something else means it has to, at least, be a member of an essentially ordered explanatory series, which means that all our conclusions from above still hold true.

To substantiate this even further, consider the question at the forefront of this post: can a brute fact be part of a convergence of multiple explanatory chains? This doesn't seem possible since, again, a brute fact cannot have an explanation, by definition, and therefore it cannot have antecedent explanatory members. That is to say, a brute fact cannot be reliant upon another fact for its intelligibility, much less multiple facts. Furthermore, based on our intelligibility argument above, what we can also say is that if C is intelligible, then, even if it is part of multiple interwoven explanatory chains, we can safely say that none of the antecedent members in these chains contains a brute fact.

In summarization we've concluded many things. First, because of the nature of explanation itself, as well as essentially ordered explanatory series, brute facts are simply impossible. There is, logically, nowhere they can fit in chains of explanation, and a chain of explanation is the only place they would go if they were possible, since brute facts are defined in terms of explanation. Second, because of the nature of explanatory chains, if a fact or state of affairs is intelligible, then it follows that it cannot be associated with a brute fact. Third, no matter how interconnected and interwoven multiple explanatory chains are, they still retain their nature as essentially ordered series and our notion of explanation--with which the whole post is founded on--and our conclusions regarding the impossibility of brute facts remain intact.
[1] See the article on the Principle of Sufficient Reason
[2] Let it be noted that this is one of the most crucial points in my argument. For everything from here on out follows from, and is entailed by, this definition.
[3] Note that neither can a brute fact be the lowest member in an explanatory chain, since in order to be the lowest member, some member would come before it and this member would have to explain it, which would contradict the definition of a brute fact. Yet I don't think anybody would entertain this idea since usually a brute fact is seen to occur at the beginning of a long line of explanations, and not at the end.

Sunday, July 10, 2016

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.

[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.

Saturday, July 9, 2016

Where have I been?

My posting has been sparse as of late, to say the least, and this is due to a multitude of reasons. First, my mother-in-law was diagnosed with cancer a few weeks ago, and my wife has been taking it pretty hard, as would be expected. The good news is that her prognosis is extremely favorable, and most likely in a few weeks she'll be completely cancer free. The Lord is good, in his own analogous way.

Second, my wife and I have been doing some major landscaping to our house. We decided to install sod in our 2000 square foot backyard by ourselves, or should I say by myself. Anyway, the job was extremely stressful because our backyard soil needed to be tilled and sifted because of all the rock and debris due to the fact that we live by the mountains -- this is all incredibly fascinating, I know. And the sod had a deadline of when it was to be shipped so I needed to have it ready by that deadline -- no pressure. Oh yeah, and did I mention I was working in the 105 degree heat, to prepare said soil?Yay El Paso! But, the sod was delivered and installed this past week, and I'm freaking glad that's done with.

Third, I was barely informed a few weeks ago that I will also be teaching physics this upcoming year, which I was stoked about. However, that means that I have to prepare lessons, and labs, before school starts -- because I'm a good teacher, dammit.

Anyway, there's been plenty on my plate as of late, but I promise that I will start blogging more. In fact, I have the next installment of my review of Carroll's book coming out in just a few days, so stay tuned.

Wednesday, June 15, 2016

I'm one step away from being an atheist

Readers of this blog know that I believe in God, and am, obviously, a theist. And most know that I also believe that God's existence can be rationally justified -- as I have attempted to demonstrate on this blog -- even if not everyone finds such justification to be overwhelmingly persuasive. I, thus, believe that my belief in God is rationally grounded.

So how, then, can it be the case that I am "one step away from being an atheist"? Is this an exaggeration? Well kind of, but...not exactly. Let me explain.

My daughter Norah is currently sixteen months old. She's the light of my life, and that which puts everything in perspective. She gives my life more meaning and joy than I ever thought was possible. My first twenty-four years of existence without her pales in comparison to the life that I now enjoy with her and my wife. The love that protrudes from my heart to her being is transcendent and unparalleled. She is my life.

And, unfortunately, as a normal parent, I constantly hear stories of the tragedies that befall parents with children. Heck, my wife works as a neonatal intensive care nurse, and comes home with horrific stories of infants dying and suffering every week, it seems. When I hear of these stories I am always grieved, and I immediately wonder what I would do in those situations. I mean, seriously, what would I do if something happened to my daughter?

Well, many things would happen, and none of them good, I can tell you that. But one action that I genuinely think would be a strong possibility is that I would abandon all belief in a God. To lose the most precious thing I have ever laid eyes on, and have completely given my heart to, would destroy me, and it would annihilate any belief in a God that has even an ounce of love. If something happened to my daughter I would curse God forever, and lose any heart that any such maximally loving being existed at all. That's it, I would be an atheist at heart.

However, there's an inconsistency here that many attentive readers may have picked up on. As I just said, and as anyone would acknowledge, these events happen constantly every day -- children are dying needlessly every minute. How, then, can I sit here and say that one child's potential death would be a sufficient condition for my non-belief, and yet this potential is being realized in thousands of other families every day? That is, how can I consistently say that one turn of events is enough to convert me to atheism, when these very events are ubiquitous in the world we inhabit, and yet nevertheless continue to believe in God?

I think that the answer here is to be found in emotion. No matter how rationally justified and reasonably held our beliefs are, they are still, most likely, predicated on emotion, more than reason. In fact, this is already something that psychologists have inferred. So, even though I believe that the existence of God is rationally justified, it is the case that a flood of emotions so significant and so powerful can overthrow this belief. And it's important to note that this is the case with anyone -- emotion can easily overthrow anyone's reasonably held beliefs, especially if one does not realize that this is occurring. What this also means is that my reasons for believing in God are not purely rational either. They are most likely rooted in just as much emotion as they are reason. In fact, it means that most of our reasonably held beliefs are probably predicated more in emotion than in reason.

So, even though I do in fact have rational justifications for why a "good" God would allow suffering and evil, when this suffering and evil lands on my front door, my emotion is enough to supersede such justification. This isn't always a good thing, but it's the condition of human nature and thought nonetheless. However, though it might not always be a good thing -- when considered from a purely rational perspective -- this sway of emotion is a form of justification in itself, and by that I mean that if one's child unfortunately dies, they are indeed warranted in entailing atheism from this event. I mean, how can they not be warranted? Because they should know William Lane Craig's logical arguments against the problem of suffering? Come on. If God made us, then he made us with a rational faculty that is just as sensitive to emotion as it is to reason -- in fact, it may be even more sensitive to emotion. Therefore, I don't see how God can be upset that an individual infers atheism from tragic and sorrowful circumstances, since God's the one who arranged our cognitive faculties to be swayed in this way to begin with! But, I digress.

To come back to me personally, I'm not even sure if what I've said is correct. That is, I don't know for sure that if the aforementioned circumstances obtained, that I would abandon theism on emotional grounds. I say this because I used to think the same regarding my father. Three years ago my father was killed crossing the street in a residential area by an idiot going fifteen over the speed limit. I always thought that if something like this happened, then, it would drive me away from God. But, here's the thing, it actually brought me closer to God. Contrary to my thoughts, the pendulum swung the other way. So maybe I'm not as close to atheism as I thought. Who knows?

What I think is important here is that we need to be aware of how powerful our emotions are, and how fragile our "rationally justified" believes are. We tend to think that we're straight-shooting logicians, unaffected by the throws of emotion and sentiment, but chances are we're always a few emotional steps away from whatever belief we most oppose.

Tuesday, May 24, 2016

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.

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