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Is the Passage of Time Real or Just an Illusion?

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One of the main targets of Sean Carroll's new book, The Big Picture: On the Origins of Life, Meaning, and the Universe Itself (Dutton, 2016), is causality. Like many naturalists, he sees where the causal chain leads—a series of contingent causes demands a necessary First Cause. So if you want to avoid a First Cause, you must get rid of causality.

As discussed in an earlier post, Carroll's first attempt appealed to the conservation of momentum. It wasn't clear how that principle undermines causality, and Carroll showed many other signs of confusion.

Later in the book, he tries to refute causality again, but this time using a controversial theory of time, known as the "B-theory" or "tenseless" theory of time (Carroll never uses these terms, but they indeed describe his view.)

Philosophers distinguish between two major theories of time, and it's worth noting that the philosophical community is generally split between the positions.

First is the A-theory, which is the common-sensical view that the passage of time is a real feature of the world, and not merely some mind-dependent phenomenon. This position holds that time is tensed, which means the past, present, and future are objectively real—in other words, tense is real (i.e., we can accurately use the "past tense"). If you asked the average person on the street how they understand time, they would likely give an A-theory description.

B-theorists, on the other hand, hold that the flow of time is an illusion, that time is tenseless such that past, present, and future are just illusions of human consciousness. This would imply that temporal becoming (e.g., growing older) is not an objective feature of reality.

If the B-theory were true, causality would indeed become trickier. Some would say that on the B-theory, causality would disappear altogether, while others more modestly claim it still exists, just in a more constricted, nuanced fashion. Either way, if your goal is to disprove causality, the B-theory is your best bet since causality is an obvious feature of reality on the A-theory, but not so on the B-theory.

So other than trying to avoid the conclusion of a First Cause, why does Sean Carroll promote the B-theory of time? Unfortunately, he doesn't tell us in his book. He doesn't acknowledge the two competing views, nor the present debate over which is true. He just asserts the B-theory as true, stating without elaboration, "In reality, both directions of time are created equal" (55), which is only true on the B-theory of time.

Carroll doesn't engage serious scholars who challenge the B-theory of time, nor any arguments for the A-theory. (William Lane Craig, one of the most prominent A-theory proponents, has written at least four scholarly books on the topic. Presumably, since Carroll debated Craig on topics that broached the philosophy of time, he was familiar with those works. But he never acknowledges them in The Big Picture.)

In his book, Carroll merely assumes the B-theory of time is true, without evidence or argument, and then uses that in his quest to show that causality is not a real feature of fundamental reality.

As in his earlier chapters on causality and determinism, Carroll does waffle a bit in this section. While he doesn't think causality is fundamentally real, he also sees the need for causal language. He isn't willing to go as far as Bertrand Russell, who said, "The law of causality, I believe, like much that passes muster among philosophers, is a relic of a bygone age." Carroll believes such a view is "too extreme" since it contradicts our everyday experience of causes. "After all," Carroll writes, "it would be hard to get through the day without appealing to causes at all" (64).

Which is where his "poetic naturalism" comes in. Although Carroll doesn't think causality is a real feature of fundamental reality (since he holds the B-theory of time), he does think it's a useful concept to describe our everyday world, and thus should be retained, at least in the domain of our everyday experience.

But once again, as is the case with other applications of his "poetic naturalism," we're left with a contradiction. Causality is either a real feature of reality, or it's not. What Carroll essentially proposes is that at a fundamental level it's not, because the B-theory is true and thus the passage of time is illusory.

Yet if that's the case, it wouldn't be accurate to use causal language in any situation. At best, such language would create a useful fiction; at worst it would be delusory.

In the next post we'll explore Sean Carroll's take on Bayes’ Theorem of probability.

Brandon Vogt

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Brandon Vogt is a bestselling author, blogger, and speaker. He's also the founder of StrangeNotions.com. Brandon has been featured by several media outlets including NPR, CBS, FoxNews, SiriusXM, and EWTN. He converted to Catholicism in 2008, and since then has released several books, including The Church and New Media (Our Sunday Visitor, 2011), Saints and Social Justice (Our Sunday Visitor, 2014), and RETURN (Numinous Books, 2015). He works as the Content Director for Bishop Robert Barron's Word on Fire Catholic Ministries. Brandon lives with his wife, Kathleen, and their five children in Central Florida. Follow him at BrandonVogt.com or connect through Twitter at @BrandonVogt.

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  • Philpapers survey results:

    Other 542 / 931 (58.2%)
    Accept or lean toward: B-theory 245 / 931 (26.3%)
    Accept or lean toward: A-theory 144 / 931 (15.5%)

    well, that doesn't shed much light on the situation.

    Brandon, I don't see any argument for the A-theory in this article, other than calling it "common sense; I understand physicists tend to accept B-theory due to Relativity, because there are no privileged reference frames. This is a huge topic, and too much to cover in a blog post, but there are serious reasons that this view has been abandoned:

    https://en.wikipedia.org/wiki/Lorentz_ether_theory

    • "Philpapers survey results:
      Other 542 / 931 (58.2%)
      Accept or lean toward: B-theory 245 / 931 (26.3%)
      Accept or lean toward: A-theory 144 / 931 (15.5%)"

      Yes, I'm aware of that survey and that's why I wrote "it's worth noting that the philosophical community is generally split between the positions."

      However, keep in mind that the Philpapers survey is of philosophers as a whole, not those who specialize in questions about time.

      "Brandon, I don't see any argument for the A-theory in this article"

      My intention wasn't to build a case for the A-theory of time in this article, only to show that the B-theory shouldn't be assumed true, since only a quarter of philosophers accept or lean toward that view. Yet this is precisely what Carroll does in his book. His argument in this section, against causality, depends on the assumption that the B-theory is true, yet he offers no support for that view.

      As I mentioned in the article, scholars like William Lane Craig have put together an impressive case in support of the A-theory. For a popular-level case, see Chapter 4 ("The Dynamic Conception of Time") in Craig's book, Time and Eternity: Exploring God's Relationship to Time (Crossway, 2001).

    • Phil

      Hey Jimmy -- I know that you were't actually putting forth a view, but since I did major work on the metaphysics of time I wanted to throw some things out there.

      I don't see any argument for the A-theory in this article, other than calling it "common sense; I understand physicists tend to accept B-theory due to Relativity, because there are no privileged reference frames.

      The A-theory of time is perfectly compatible with an Einsteinian universe. (I actually don't think the B-theory is compatible with relativity, or any scientific theory for that matter, which is why I don't support it.) Unfortunately, for a physicist to say that a theory of physics means that a tenseless universe (B-theory) is true is usually simply the case of a good scientist being a bad philosopher.

      I actually did my undergrad thesis on the metaphysics of time. To summarize, time is simply equal to change. If there is change, then there is time. So if one wants to hold that change is a real feature of the cosmos, (which is necessary for the physicist to even do their work!) then time is also a real feature of the cosmos. It matters very little if different reference frames lead to experiencing the change at a different subjective "moment". Many making this mistake think of time as some kind of "river", like Newton thought. But that is not what time is--If change exists, then time exists.

      This view of time being equal to change actually goes all the way back to ~300BC and Aristotle. Relativity is actually much more harmonious with this view of time than the Newtonian universe and its view of time. Just goes to show that truth cannot ultimately contradict truth.

      • David Nickol

        Unfortunately, for a physicist to say that a theory of physics means
        that a tenseless universe (B-theory) is true is simply the case of a
        good scientist being a bad philosopher.

        Sean Carroll has written an entire book on time—From Eternity to Here: The Quest for the Ultimate Theory of Time. Also, he has produced a course (from "The Great Courses") titled Mysteries of Modern Physics: Time. Let's remember that what we are getting in Brandon's critique of Sean Carroll's view of time is Brandon's interpretation, which is based on a couple of sentences in The Big Picture. Sean Carroll himself does not mention the A-theory or the B-theory (as Brandon acknowledges) in the book under discussion or (based on a Kindle search) in From Eternity to Here.

        I do not think we should assume that Brandon has characterized Carroll's views on time correctly. Admittedly I have said previously that we are discussing this one book, not everything Carroll has ever written or said in a debate. But if Brandon is going to claim that Carroll subscribes to a certain specific theory, even though he acknowledges Carroll does not actually say so, I think we need to be very cautious in concluding what Carroll actually believes.

        • Phil

          I think that is very fair. And to be fair to Brandon as well, it sounds like Carroll didn't do the best job spelling it out in this book (perhaps Carroll was assuming the reader had some familiarity with his other books).

          ----------
          Carroll seems to give at least a good, brief overview of his view of time here: http://www.preposterousuniverse.com/blog/2013/10/18/is-time-real/

          While Carroll is focusing on a distinction between "emergent" and "fundamental" properties, which could in theory be a good distinction, I think he is overemphasizing how much the distinction really matters in regards to existence. As he says in the article linked above, both exist and are real. They are just at different "levels of reality".

          For example, fields and particles are at different levels of reality. A field is a more fundamental part of reality, but that doesn't make it more or less real or existent than particles. So in the end, I won't disagree that there may be a real distinction that Carroll is chasing, but it really isn't that interesting of one from a philosophical point of view.

          And as I've mentioned before, time is actually relatively simple. Time is equal to change. If things are changing then time exists.

          The next level of time is a conscious being coming onto the scene and being able to recognize the succession of change and calling it "time".

          In that sense, I would think that if Carroll says that change is a fundamental property of the material cosmos, then he would hold that time is a fundamental property as well.

          • What is being overlooked here is the distinction between philosophical time and quantitative time. Philosophical or metaphysical time, as you have said, is a quality, that of mutability. Quantitative time is a human idea. It is the mental comparison of one motion with another. Quantitative time is a physical measurement and, as every measurement, it is a human activity expressing a relationship of comparative size. Trent Horn, a modern Zeno of Elea, does an excellent job of confusing the human idea of quantitative time with philosophical time in arguing that the universe must have had a beginning (p 126, “Answering Atheism”)

          • Phil

            Hey Bob --

            Exactly, every measurement of time is a comparison, and in that sense time can be "relative". But that simply means that the rate of change of entities are speeding up or slowing down compared to one another.

            This I think is a really neat feature of Einstein's theories. What specifically is it about mass/energy that causes things to slow down their rate of change based upon proximity? I think we are still working on that question. Pretty sweet stuff.

            Trent Horn, a modern Zeno of Elea, does an excellent job of confusing the human idea of quantitative time with philosophical time in arguing that the universe must have had a beginning (p 126, “Answering Atheism”)

            While I see what you are getting at, there may be some merit to what Trent is saying.

            I too have thought about this. Time is merely a succession of changes. So if it is impossible to have a changeless material entity, then I believe one could conclude that there cannot be an infinite series of changes into the past.

            I have talked to some pretty accomplished philosophers, and most don't think a changeless material entity is possible, but some don't dismiss is right away.

            So I think the jury is still out, though I would lean towards Trent's conclusion.

            (While I don't think an infinite series of changes reaching into the past may be possible, I do think an infinite amount of matter/infinite cosmos could potentially exist. It could all be created in one single moment in the finite past.)

          • A chemistry teacher asked a student what was the elution rate of his chromatographic column. He replied, “Drip, drip, drip.” The teacher wasn’t pleased. The student wasn’t wrong. The teacher just didn’t like the relative standards for the measurements of time and volume the student had chosen. The teacher expected the student to use the relational standards chosen by convention. The student’s relational standards were obviously his cadence and the volume of a drip. The relativity of a time standard does not imply any acceleration or deceleration.

            That there is a commonly accepted standard of quantitative time, does not imply that ‘an increment of absolute time’ has any meaning. This implication must be true for Trent Horn’s argument to be valid.

            We experience the non-extended, non-quantitative now of mutability, whereas quantitative time is a human thought. The past and the future are qualitatively, not quantitatively, distinct from now.

            The relationship of extension among material things is real as is their relative motion. In contrast, quantitative ‘space and time’ are human thoughts. Similarly, change is real, but ‘a series of changes’ requires mental definition.

          • Will

            There is one quantitative difference between the past and the future, and that is the fact that entropy is always lower in the past, and higher in the future. I don't know if that's the only thing that gives time its arrow, but it is a quantitative physical difference.

          • Facile1

            I like to think that it is not possible to understand 'time' as separate from 'matter'. GOD did not create 'time' anymore than He created 'darkness' or 'space'. But GOD created 'matter'.

            'Matter' has a past and a future. Thus 'matter' has a beginning and an end. And the difference between the two points is all a matter of time. :-)

            So while 'death' may be an irrelevant abstraction to the Giver of life (eternal), the time we were given in this plane of existence is 'real' and not an 'illusion'.

            GOD's gift of life is the gift of eternity (regardless of whether our lifespans were terminated at the point of conception or ended in natural death.)

          • Phil

            We experience the non-extended, non-quantitative now of mutability, whereas quantitative time is a human thought. The past and the future are qualitatively, not quantitatively, distinct from now.

            The relationship of extension among material things is real as is their relative motion. In contrast, quantitative ‘space and time’ are human thoughts. Similarly, change is real, but ‘a series of changes’ requires mental definition.

            Could you dive into this a little more, maybe with an example to illustrate this?

            The reason for this is I'm not quite sure I'd agree with a "series of changes" not being a feature of reality apart from the human mind (I might be misunderstanding you, so that's why I'd love some clarification).

            Thanks!

          • Thanks for challenging me to illustrate my claim, “Similarly, change is real, but ‘a series of changes’ requires mental definition.”

            Although citing a series of changes may illustrate logical distinctions, it would also imply that the change being divided into the series is also a logical distinction. That renders my claim a distinction without a difference. For example, noting that it is a logical process to divide embryological development into a series of logical stages, implies that embryological development as a whole is being identified as a logical stage.

            I had thought that the most fundamental error of Zeno’s argument that motion is an illusion and Horn’s argument that past time must be finite, was confounding the logic of measurement with the reality of the material property being measured. I now think there is another source of error involved.

            Two material properties, which we observe and which we subject to the logic of measurement, are extension and motion. We observe that material things are themselves extended and are also related to one another by extension. We also observe that material things can be in motion with respect to one another.

            In choosing a standard of measurement for extension, we chose one of linear extension, which we call length. In choosing a standard of measurement for motion, we choose a cyclic motion and specifically the period of its cycle, which we call time. However, we promptly forget that the standard period is a measure of motion and begin to think of it as a measure of linear extension. We thus have a standard measure of extension and a standard measure of motion, but both are viewed as expressions of linear extension. From this view, extension and motion differ only by label.

            It is this subtle inference that motion is indistinguishable from linear extension, which forms the basis of Zeno’s argument, that observed motion must be an illusion. It also forms the basis of Horn’s argument, that the universe must have had a beginning.

          • Phil

            Thank you for that. A few thoughts:

            While I absolutely agree that the specific measurements and delineation of a series can be up to the conscious entity doing the measuring, this does not mean that a real series of changes, at an ontological level, does not exist.

            The reason I would argue this must be the case is that if one holds that an ontological series of changes does not actually exist apart from a conscious mind, then it must also be true that a fully-grown oak tree can precede in existence the seed from which it came. We could apply this same thing is near everything in the material cosmos, including the cosmos itself.

            But in point of fact, the existence of the oak seed must precede the existence of a fully grown oak tree. Thus an ontological series is formed even if one could never delineate, from an epistemological point of view, where the seed objectively became a "fully-grown oak tree".

            In short, it seems that the ontological existence of real series of changes is necessary even for the physical sciences to be coherent. Without real series of changes at an ontological level, human knowledge in general becomes impossible.

          • From your reply, it is apparent that I failed to express my position.

            “Similarly, change is real, but ‘a series of changes’ requires mental definition.”

            You challenged me to illustrate this claim of a distinction between what is real and a series, which is logical. I tried to decline your challenge and let the matter drop, but you insist by proposing an illustration of a ‘real series of changes’, namely the series of changes from a seed to a fully grown oak tree.

            Classification is logical even if it is the classification of the natural properties of real material things. An example is a morphological key to the plants of North America. The classification is logical, but it would be useless if it didn’t refer to real material properties.

            Similarly, the series of stages from a seed to a fully grown oak tree is a logical classification both as a series and its several stages. As a logical classification, it refers to real change.

            The series as a whole, which you cite, is evidently a logical identification due to the fact that the first stage is arbitrarily chosen. Why not start the ‘real’ series with a sapling? Notice by having a seed as the first stage and the fully grown oak as the final stage, another series of stages is omitted. The omitted series consists of those stages from fertilization of the oak flower through development of the embryo terminating in the fully developed seed. That omission is not necessitated by reality. It is arbitrary, a logical choice, which thereby identifies as logical the series which you cite.

            Notice also that from seed to fully grown oak tree is a linear series. If you had chosen ‘the real series’ rather than your ‘logical series’ you would have identified a series from fertilization of an oak flower to the flowering of a new, mature oak tree. This ‘real series’ is not linear, like your ‘logical series’. The ‘real series’ is cyclic.

            Our disagreement is one of verbal expression. You are not flustered by the expression ‘a real series’ while I am. I judge the word, logical, to be redundant in the expression, ‘a logical series of real changes’.

          • Phil

            Thank you for further clarification.

            I absolutely agree that there are previous states that are not necessarily required for the existence of some specific future state. But it seems that most real changes do require some specific type previous state or part of a previous state (namely, that the previous state had the potentiality to bring about the existence of the "next state").

            In short, it seems that you could never get to the point, even in a cyclical series, where there wasn't something logically necessary about the previous state to be able to bring about the following state.

            Shoot, even if one could reduce all of the material cosmos to 2 logical states that have been cycling, you'd still have the problem that Trent is pointing towards...it couldn't be an infinite cycle into the past.

          • David Nickol

            And as I've mentioned before, time is actually relatively simple. Time is equal to change. If things are changing then time exists.

            You are actually the first person I have ever run into who has claimed time is simple!

            Here's a question, though. Isn't it the Catholic belief (or at least the Thomist belief) that there is no past or future for God, and that God sees all of time as existing at once? If so, how is it possible to maintain that the future already exists, at least in some sense? It seems like "eternalism" to me.

          • Phil

            You are actually the first person I have ever run into who has claimed time is simple!

            Ha, it may be more correct to say that the ontological existence of time is relatively simple, while the subjective personal experience of time is more complex.

            Isn't it the Catholic belief (or at least the Thomist belief) that there is no past or future for God, and that God sees all of time as existing at once? If so, how is it possible to maintain that the future already exists, at least in some sense? It seems like "eternalism" to me.

            Yes, God is changeless and therefore eternal (see how change and time go together!).

            This means that there is no future for God. That means it makes no sense to say God "knows the future", because there is no future for God!

            For God there is only present. So all of our past, present, and future actions are equally present for God. This doesn't mean that the future states of the cosmos actually exist, it merely means that God sees all of creation at one single moment.

            In short, the future and past don't collapse into the present because of the fact that God doesn't have a past or future. Rather God stretches himself out to encompass all past, present, and future in a single, eternal "now".

            Yes, it is impossible for us to wrap our head fully around what this is like since we are temporal and not eternal.

        • Sean Carroll himself does not mention the A-theory or the B-theory (as Brandon acknowledges) in the book under discussion or (based on a Kindle search) in From Eternity to Here.

          Here we have Carroll accepting eternalism:

          Personally, I find the eternalist block-universe view to be perfectly acceptable [...] (The Reality of Time)

          And here we find eternalism linked to the B-theory of time:

          Eternalism is a philosophical approach to the ontological nature of time, which takes the view that all points in time are equally "real", as opposed to the presentist idea that only the present is real[1] and the growing block universe theory of time in which the past and present are real while the future is not. Eternalism is the view that each spacetime moment exists in and of itself. Modern advocates often take inspiration from the way time is modeled as a dimension in the theory of relativity, giving time a similar ontology to that of space (although the basic idea dates back at least to McTaggart's B-Theory of time, first published in The Unreality of Time in 1908, only three years after the first paper on relativity). This would mean that time is just another dimension, that future events are "already there", and that there is no objective flow of time. It is sometimes referred to as the "block time" or "block universe" theory due to its description of space-time as an unchanging four-dimensional "block",[2] as opposed to the view of the world as a three-dimensional space modulated by the passage of time.

          If you cannot point out any way that Carroll's take on eternalism differs from what currently goes as the B-theory of time, I think your criticism is misplaced.

          • David Nickol

            If you cannot point out any way that Carroll's take on eternalism differs from what currently goes as the B-theory of time, I think your criticism is misplaced.

            My point—which I stand by—is that I do not think we should assume Brandon has correctly interpreted Sean Carroll's views on the nature of time. Note that I didn't say Brandon is wrong to categorize Carroll's view as equivalent or identical to the "B-theory." I am saying I don't think we should assume Brandon is right and discuss his interpretation of Carroll's views on time as if they came from Carroll himself.

            Stepping back and looking at Brandon's post as a whole, he asks if the passage of time is real or just an illusion. Carroll says it is real—as I understand him—but Brandon seems to maintain that whatever Carroll says, he can't really mean it, and so Carroll's real position is that time is illusory. It is possible that Brandon's understanding of Carroll is correct, but I certainly still maintain we should not assume it.

            Let me add that as I understand Brandon, he rejects a basic tenet of Carroll's "poetic naturalism"—the idea of levels of reality. So when Carroll says that "in reality, both directions of time are created equal," Brandon rejects the idea that at the most fundamental level that can be true, but that in our universe (because of the initial conditions and because of entropy) the arrow of time is very real and only points one way. Brandon seems to believe (and he can confirm or deny this), that if something is the case at any level of reality, it is the case at all levels. Or perhaps he simply doesn't buy the concept of levels of reality. So it seems to me Brandon simply rejects a basic tenet of Carroll's method of looking at reality. Given this, it is hard to see how Brandon could agree with anything Carroll says.

          • "My point—which I stand by—is that I do not think we should assume Brandon has correctly interpreted Sean Carroll's views on the nature of time."

            There's only one way to verify this--read the book! See for yourself! It's not difficult, especially since I'm quoting specific page numbers.

            Your comment could be made about every book review ever written, and thus doesn't contribute much to the discussion here. Of course we could question whether any reviewer has fairly represented the author's points. But such radical skepticism will get us nowhere.

            Finally, this series of post, as noted at the beginning, is an attempt to engage Carroll's arguments in his latest (and most celebrated) book. That's it. I'm not reviewing his entire corpus, nor all of his ideas.

            "Brandon seems to maintain that whatever Carroll says, he can't really mean it, and so Carroll's real position is that time is illusory."

            ...and ironically, this proposal comes on the heels of you accusing me of misrepresenting someone's views. Here's a prime example! I simply never said or implied what you assert.

            "Brandon seems to believe (and he can confirm or deny this), that if something is the case at any level of reality, it is the case at all levels."

            I'm not sure I'd state my views that way, primarily because, as I've noted more than once, I don't accept the premise that reality has multiple "levels", domains that sometimes conflict. To me, reality is a unified whole. There is only one reality. There are not alternate realities (outside of science fiction and imaginations.)

            Thus if something in true in reality, it's true in reality--it's not true in some parts of reality but not others, it's not partially true here and partially true there, it's not true in some realities and not others.

          • My point—which I stand by—is that I do not think we should assume Brandon has correctly interpreted Sean Carroll's views on the nature of time.

            If it looks like a duck, moves like a duck, and quacks like a duck, then it's probably a duck, and we're justified in treating it as a duck until there is a reason not to. Pragmatically treating it as a duck is not the same thing as assuming on a metaphysical level that it's necessarily a duck.

            Stepping back and looking at Brandon's post as a whole, he asks if the passage of time is real or just an illusion. Carroll says it is real—as I understand him—but Brandon seems to maintain that whatever Carroll says, he can't really mean it, and so Carroll's real position is that time is illusory.

            Actually, I suspect that Brandon dislikes the principle of "it's real if it is useful", which we see at play in Carroll's writing:

            Personally I think that the whole issue is being framed in a slightly misleading way. (Indeed, this mistaken framing caused me to believe at first that Lee and I were in agreement, until his book actually came out.) The stance of Maudlin and Smolin and others isn’t merely that time is “real,” in the sense that it exists and plays a useful role in how we talk about the world. They want to say something more: that the passage of time is real. That is, that time is more than simply a label on different moments in the history of the universe, all of which are independently pretty much equal. They want to attribute “reality” to the idea of the universe coming into being, moment by moment. (The Reality of Time)

            More reason to doubt Carroll's way of thinking about what is 'real' comes from his Free Will Is as Real as Baseball. Given the extensive discussion in the previous blog post in this series, I think it's fair to say that Carroll means that free will is driven by impersonal forces, not personal ones. Surely one can be justified in questioning whether free will is therefore 'real'.

            Let me add that as I understand Brandon, he rejects a basic tenet of Carroll's "poetic naturalism"—the idea of levels of reality.

            Possibly, or he rejects the idea of "levels of reality" combined with Carroll's rejection of downward causation. I suspect that this rejection injects into the "levels of reality" notion the property that "domains that sometimes conflict", to steal a phrase from @bvogt1:disqus's subsequent response to this comment of yours.

      • I actually did my undergrad thesis on the metaphysics of time. To summarize, time is simply equal to change. If there is change, then there is time. So if one wants to hold that change is a real feature of the cosmos, (which is necessary for the physicist to even do their work!) then time is also a real feature of the cosmos.

        What you say here reminds me of Michael Tooley:

            To sum up, then, the difference between a static conception of the world and a dynamic one comes to this. According to a static conception, what states of affairs there are does not depend upon what time it is. Change, consequently, cannot be a matter of a change, over time, in what states of affairs exist. It must be a matter simply of the possession, by an object or by the world as a whole, of different intrinsic properties at different times.
            According to a dynamic conception of the world, by contrast, what states of affairs exist does depend upon what time it is. As a consequence, the totality of monadic states of affairs which exist as of one time, and which involve a given object, may differ from the totality that exists as of some other time, and it is precisely such a difference that constitutes change in an object, rather than merely the possession by an object of different properties at different times. Similarly, change in the world as a whole is a matter of a difference in the totality of states of affairs that exist as of different times, and not merely a matter of the possession of different properties by different temporal slices of the world. (Time, Tense, and Causation, 16)

  • Reminds me a lot of discussing the existence of objective morality. If objective morality is illusory, it wouldn't be accurate to use this kind of language in any situation.
    i.e. "All men are created equal"

  • David Nickol

    Like many naturalists, he sees where the causal chain leads—a series of
    contingent causes demands a necessary First Cause. So if you want to
    avoid a First Cause, you must get rid of causality.

    Brandon:

    It would be a courtesy, even if (though?) you don't actually believe it, to write as if you accept that when Sean Carroll—who is a professor of physics—states what he holds to be true about matters of physics, he actually and honestly has arrived at his conclusions as a physicist, not as an atheist who must take care to avoid certain scientific viewpoints lest he give ammunition to religious apologists.

    Also, it seems to me that non-physicists are much more likely to let their religious beliefs influence what they choose to believe about physics than are physicists.

    • "It would be a courtesy, even if (though?) you don't actually believe it, to write as if you accept that when Sean Carroll—who is a professor of physics—states what he holds to be true about matters of physics, he actually and honestly has arrived at his conclusions as a physicist, not as an atheist who must take care to avoid certain scientific viewpoints lest he give ammunition to religious apologists."

      I agree, just as it would be a courtesy not to accuse me of things I never said. I never said "avoiding a First Cause" was Sean Carroll's personal motivation for denying causality. I simply noted:

      1) Carroll understands that a causal chain of contingent events implies a First Cause (which he makes clear in his book)

      2) Many naturalists (though not necessary Carroll) deny causality for this reason

      3) That if someone wanted to avoid a First Cause, they should get rid of causality

      You can draw your own conclusions from those observations, but nowhere did I say that Carroll himself rejects causality because of his prior atheistic commitments.

      That said, it is difficult to attribute Carroll's acceptance of the B-theory of time to "his conclusions as a physicist" since he offers no support for his view from the domain of physics. If physics led him to the B-theory of time, surely he would explain how or why, but he doesn't. To me, that's quite telling.

      "Also, it seems to me that non-physicists are much more likely to let their religious beliefs influence what they choose to believe about physics than are physicists."

      The opposite seems true to me, especially since the question of God's existence is independent of physics. Though physics can support philosophical arguments for or against God, the question is properly a philosophical or religious one.

      In my experience, atheists/naturalists are more predisposed to study physics, biology, or chemistry because of their naturalistic commitments. In other words, their unbelief drives them into science, not the other way around.

      • David Nickol

        I agree, just as it would be a courtesy not to accuse me of things I never said. I never said "avoiding a First Cause" was Sean Carroll's personal motivation for denying causality.

        And I didn't accuse you of saying anything you didn't say. Now, my implication is fairly clear, just as your implication is clear that Carroll picks his beliefs about physics to avoid unwanted philosophical implications.

        It is actually difficult, and perhaps impossible, to know whether a person (including one's own self) is letting his philosophy/religion influence his beliefs about science or vice versa. You might say this is due to our "fallen nature." :P

        • You accused me, by implication, of "[writing] as if [Carroll]...arrived at his conclusions as...an atheist who must take care to avoid certain scientific viewpoints lest he give ammunition to religious apologists."

          That's an accusation. You're suggesting a motivation for which there was no factual basis.

          On the other hand, I did not imply motivations on Carroll's part. I simply laid out his own case, and his own words.

          • David Nickol

            That's an accusation. You're suggesting a motivation for which there was no factual basis.

            It is part of the human condition that you can only interpret what Sean Carroll says, I can only interpret what you say, and you can only interpret what I say. It's all very imperfect. But I think part of dialogue, especially where we know there is strong disagreement, is not to take personal offense when we believe we have been misinterpreted. I am generally quite careful to say, "It seems to me you are saying X," instead of, "You are saying X!" Implicit in such a statement is an invitation to respond, "It may seem so to you, but X is actually not what I meant."

            I am not quite sure "that's an accusation" has any place in reasonable, civil dialogue, which this discussion has been so far. It suggests I am out of bounds when I interpret you (rightly or wrongly) in a way you don't want to be interpreted. But, as I say, trading interpretations back and forth is the only way to try to understand each other. I don't think we should need to walk on eggshells.

      • OverlappingMagisteria

        Perhaps it is not your intention, Brandon, but I certainly got the same impression: that you think Carrol purposely avoids certain views because the may lead to uncomfortable conclusions. I've gotten this impression a few times so far during this series. In addition to the bit David quoted I'll add these:

        So other than trying to avoid the conclusion of a First Cause, why does Sean Carroll promote the B-theory of time? Unfortunately, he doesn't tell us in his book.

        (Kinda sounds like your saying that the only reason he has is to avoid the conclusion)

        From the previous article:

        To do so, Carroll admits, would require God-like programming (which he immediately dismisses, uncomfortable with any conclusion that may result in God.)

        (sounds like you're saying that he dismisses the idea just because it might lead to God)

        Again... it seems that you don't mean it this way, based on your comment, but it can be read that way.

        • "Perhaps it is not your intention, Brandon, but I certainly got the same impression: that you think Carrol purposely avoids certain views because the may lead to uncomfortable conclusions. I've gotten this impression a few times so far during this series."

          Them that's a fault of my unclear writing, and I take responsibility for that. I'll try to be clearer in the future. But unclear writing is not accusation, as David suggests.

          "Unfortunately, he doesn't tell us in his book."

          "(Kinda sounds like your saying that the only reason he has is to avoid the conclusion)"

          No, I'm saying he doesn't tell us the reason. In fact, I literally wrote that: "Unfortunately, he doesn't tell us in his book."

          "sounds like you're saying that he dismisses the idea just because it might lead to God"

          In this particular case, yes. But that's only because it's what Carroll himself writes! He dismisses the idea of an omnipotent computer because it "would require godlike powers"--that's his only reason. In other words, it can't be true because we know there's nothing with godlike powers (or, to say it another way, because there is no god/God.)

          "Again... it seems that you don't mean it this way, based on your comment, but it can be read that way."

          Many passages can be interpreted many ways. But hopefully you agree that nothing I've said has been untrue, and that I've fairly quoted Carroll's own words and described his own positions.

          • OverlappingMagisteria

            Take a look at the full quote, which you truncated:

            So other than trying to avoid the conclusion of a First Cause, why does Sean Carroll promote the B-theory of time? Unfortunately, he doesn't tell us in his book.

            Do you see how the first sentence would strongly give the impression that you think his only reason is to avoid a first cause? You didn't simply say "Carol gives us no reasons." You bring in the whole idea of avoiding a first cause. I don't see what that first sentence does other than hint (without outright saying it) that Carol has underlying motivations.

            I'll take your word on the god-like computer quote since I don't have the book in front of me. Although I'll note that a god-like computer is not quite the same as God (I think you'd agree) so it might not be as cut-and dry. Perhaps Carol needs clearer writing! :-)

            Many passages can be interpreted many ways. But hopefully you agree that nothing I've said has been untrue, and that I've fairly quoted Carroll's own words and described his own positions

            As you've shown, the things you've said can be interpreted as true.. but they can also be easily interpreted as false as well. I can't really tell if you've fairly represented Carol since I have not read his book (though the folks at Estranged Notions seem to think you have not, in case you care)

      • TomD123

        A few thoughts on this and the post

        1) B-theory does not get rid of causality, A-theory does. A-theory goes hand in hand with presentism. If the past does not exist, how can we truthfully say anything of the past caused anything in the present?

        2) Other physicists besides Carroll have explained why contemporary physics supports the B-theory over the A-theory. To say that Carroll must give his reasons for thinking so is like saying he also must give his personal reasons for thinking F=ma or something like that

        3) Catholics ought to reject A-theory because it undermines God's omniscience, specifically, His foreknowledge of future free choices.

        4) This is a prime example where a lot of Christians support something that is unpopular in the scientific community in order to support their religious beliefs (it seems that a lot of Christians support the A-theory to save the Kalam argument). But this is not a good approach because #3 above (I am not accusing anyone in particular of doing this, just an observation in general)

        • "B-theory does not get rid of causality, A-theory does. A-theory goes hand in hand with presentism. If the past does not exist, how can we truthfully say anything of the past caused anything in the present?"

          This has things precisely backward. On the A-theory, past moments do exist, each as some present moment at a particular time, and we can thus say that past events do cause present events.

          "Other physicists besides Carroll have explained why contemporary physics supports the B-theory over the A-theory. To say that Carroll must give his reasons for thinking so is like saying he also must give his personal reasons for thinking F=ma or something like that."

          Once again, my purpose in these posts is to review Carroll's book. It wasn't to argue whether the B-theory is true, or to take on the arguments of its supporters. I simply noted that Carroll does none of this in his book. He just asserts it as true, which I think is deeply misleading to readers not familiar with the controversy.

          And I strongly disagree with your comparison of the B-theory of Newton's second law of motion. As has been noted elsewhere in this thread, only a quarter of philosophers even hold to the B-theory. Contra Newton's laws, it's certainly not the consensus position. So if you're going to assume it's true, you need to provide evidence or support.

          "Catholics ought to reject A-theory because it undermines God's omniscience, specifically, His foreknowledge of future free choices."

          This is not true. I recommend reading William Lane Craig's book on this, Time and Eternity, or the Appendix on time in Trent Horn's book, Answering Atheism. Craig is non-Catholic but his defense of God and the A-theory is time is mostly compatible with Catholic belief.

          "This is a prime example where a lot of Christians support something that is unpopular in the scientific community in order to support their religious beliefs (it seems that a lot of Christians support the A-theory to save the Kalam argument). But this is not a good approach because #3 above (I am not accusing anyone in particular of doing this, just an observation in general)."

          A few things: first, you're suggesting that the A-theory is some marginal position without much support. But this is misleading, since the B-theory has barely more support. The large majority of philosophers (and I presume scientists) simply are not well-versed in philosophy of time and don't have an opinion.

          Second, I don't know a single Catholic who supports the A-theory of time merely to "save the Kalam argument." Perhaps you do? If so, who? You say it's "just an observation in general" but provide no examples. I know less than a few dozen Catholics who are even familiar with the Kalam argument. Most Catholics I know hold the A-theory view (even if they aren't familiar with the term) not because of the Kalam, but because it jives with their intuition and common sense experience.

          Third, strong efforts have been made to show that the Kalam argument doesn't require an A-theory view of time, but is in fact compatible on the B-theory. I'm not sure whether you're familiar with those arguments.

          • TomD123

            A couple of things:

            1) You say "On the A-theory, past moments do exist." Now, A-theory technically deals with the nature of propositions, so I will stick to "presentism" which is the view typically associated with A-theory of time. And presentism certainly denies that past states exist. The most common view which holds that past moments do exist is eternalism. However, it seems difficult to reconcile eternalism and A-theory.

            2) The comparison between F=ma and B-theory is faulty in the respect that you pointed out. However, it is my understanding that at least in the physics community, A-theory is largely rejected. Physicists have given arguments against A-theory.

            3) I would like to push the issue that God's foreknowledge is incompatible with presentism. In a comment below I gave an argument for this conclusion. Moreover, God's immutability is moreover incompatible with A-theory. One problem with William Lane Craig's analysis is that God enters in to time with creation. (Another problem is that Craig is a Molinist. Now, my argument against A-theory based on God's foreknowledge that I posted below can be given without rejecting middle knowledge. That said, Craig's analysis is going to fail for another reason as well, viz. that he thinks counterfactuals of freedom have truth value which, in my view, undermines libertarian freedom).

            How can God know the free choices of future people if there is no future free choice to be known? If the future doesn't exist (as presentism and growing block universe theories have it), then how can God (or anyone) know anything about the future?

            4) I think the Kalam requires the A-theory. Moreover, philpapers reports that philosophers or religion support A-theory more than other philosophers. In conversation and anecdotally it seems to be the case that acceptance of the Kalam in particular correlates with the A-theory. I think there aren't any good arguments for the A-theory. These are all observations, and maybe I am incorrect to draw conclusions from them, but I wouldn't put too many eggs in the A-theory basket considering it is the minority view, seems to be undermined by modern physics, and is theologically worrisome insofar as it denies God foreknowledge

        • Will

          1) B-theory does not get rid of causality, A-theory does. A-theory goes hand in hand with presentism. If the past does not exist, how can we truthfully say anything of the past caused anything in the present?

          FWIW I agree. How can something that doesn't exist cause anything?

    • Will

      Carroll never claims time is an illusion in the book, only that entropy is critical to understanding time in physics, and that's true. From his blog:

      In one sense, it’s a silly question. The “reality” of something is only an interesting issue if its a well-defined concept whose actual existence is in question, like Bigfoot or supersymmetry. For concepts like “time,” which are unambiguously part of a useful vocabulary we have for describing the world, talking about “reality” is just a bit of harmless gassing. They may be emergent or fundamental, but they’re definitely there. (Feel free to substitute “free will” for “time” if you like.) Temperature and pressure didn’t stop being real once we understood them as emergent properties of an underlying atomic description.

      The question of whether time is fundamental or emergent is, on the other hand, crucially important. I have no idea what the answer is (and neither does anybody else). Modern theories of fundamental physics and cosmology include both possibilities among the respectable proposals.

      http://www.preposterousuniverse.com/blog/2013/10/18/is-time-real/

      Next Brandon is going to accuse Carroll of saying temperature isn't real because it's emergent? I've completely lost interest in discussing the book here, because we aren't discussing the book or Carroll's positions.

  • David Nickol

    B-theorists, on the other hand, hold that the flow of time is an
    illusion, that time is tenseless such that past, present, and future are
    just illusions of human consciousness. This would imply that temporal
    becoming (e.g., growing older) is not an objective feature of reality.

    From Eternity to Here: The Quest for the Ultimate Theory of Time, by Sean Carroll:

    The arrow of time, then, is a brute fact about our universe. Arguably the brute fact about our universe; the fact that things happen in one order and not in the reverse order is deeply ingrained in how we live in the world. Why is it like that? Why do we live in a universe where X is often followed by Y, but Y is never followed by X?

    The answer lies in the concept of "entropy" that I mentioned above. . . . [Kindle Edition, Loc 554 of 9976]

  • Will

    Is time real. Carroll says yes, in both his book, and in this youtube video. The question of whether something is fundamental is not a question of whether something is real.

    https://www.youtube.com/watch?v=FVINOl0Ctfk

    • The question isn't whether time is real. The question is, as this post notes in its very title, "Is the passage of time real?"

      • Will

        Carroll not only thinks time is real, but also the arrow of time , thanks to entropy. Carroll simply does not embrace a cut and dried B theory of time.
        We know for a fact that there isn't an objective fact about time independent of an inertial reference frame, so the perception of time is dependent upon that, among other thing. Carroll is doing cutting edge physics, it's a mistake to shuffle him into A theory or B theory. We should talk about "Carroll's Theory".

  • TomD123

    I don't understand the problem with B-theory. One point I would like to make is that Catholics ought to accept it. Typically, B-theory is associated with "eternalize" which is the view that all times are equally real and that the past, present, and future are indexical rather than absolute. In any case, here is the argument:

    1) If God knows the future, the future exists
    2) God knows the future (Catholic doctrine)
    3) Therefore the future exists
    Therefore, eternalism is true

    Now, premise 1 is the one that needs a defense. But notice this: in order for God to know whether or not some person makes a particular choice, there must be a fact of the matter as to whether or not said person makes the choice. For instance, in order for God to know that Sean writes the book, it has to be true that Sean writes the book. This means that in order for God to know the future, there has to be a fact of the matter as to what choices people make in the future.

    However, if these choices do not exist, as presentism would have it, then how can there be a fact of the matter as to what choices are made? One option is because they are determined by causes in the present. Yet this seems to contradict free will (unless you are a compatibilist, but this is not very popular in Catholic circles especially). Another option is to say that God causes our choices and He knows what choices we are going to make because He knows what choices He is going to cause. However, this seems to place God in time. Because if God knows our choices by knowing what choices He is GOING to cause, then God is in time contra Catholic doctrine. But if God knows what choices people make by knowing what He IS CAUSING, then it seems to follow that the choices exist.

    Therefore, premise 1 seems eminently reasonable. So Catholics should reject A-theory

  • David Nickol

    Anyone who thinks the passage of time is just an illusion must not do 30 minutes a day Mondays through Saturdays on the treadmill at the gym.

  • Peter

    "In reality, both directions of time are created equal" (55), which is only true on the B-theory of time

    Sean Carroll asserts that there is no absolute beginning to time, implying that the universe has always existed and that there is no need for a God to have created it.

    According to Carroll, the big bang is a quantum event where, due to quantum time reversal, the arrow of time begins to point in two opposite directions, into the past and into the future. This makes the universe eternal in the past and in the future, without beginning or end, and therefore without any need of having been created.

    Recourse to an eternal universe was considered useful in the period between the Enlightenment and the beginning of last century. In that period an eternal universe was deemed to be one where time had no beginning. If time had no beginning, there was no need for a God to have begun it.

    However, the big bang has changed all that. It marks the spot where the arrow of time begins to point in opposite directions, where time begins to flow into the future and into the past. The appearance of an eternal universe is just an illusion caused by time flowing both backwards and forwards from a single starting point.

    The universe may appear eternal but time has a beginning, and if time has a beginning, something or someone must have begun it.

    • David Nickol

      According to Carroll, the big bang is a quantum event where, due to
      quantum time reversal, the arrow of time begins to point in two opposite
      directions, into the past and into the future. This makes the universe
      eternal in the past and in the future, without beginning or end, and
      therefore without any need of having been created.

      I am not sure where you got this. If there is one thing Sean Carroll is very clear on, it is that the arrow of time points in only one direction because of the very low entropy in the universe following the big bang. "Both directions of time are created equal," but that does not mean that at the big bang, the arrow of time pointed both to the past and to the future! Our experience of the arrow of time only pointing one way is not an illusion. It is, however, not "fundamental" but rather emergent. But it is absolutely real.

  • There is no contradiction. Carrol doesn't say that causality is not real, he says it is not a fundamental feature of our universe. Again it is an emergent feature of the universe, it is an abstraction we use to form a context to interpret what we observe and remember.

    We know the sun does not rise or set. We know that every time we talk about the sun rising or setting we are being technically inaccurate. It is just that saying things like "let's go for a walk when the relative positions are such that it appears the sun is close to the horizon and moving towards it" is clunky. We talk about the sun rising and setting and, in most circumstances we think of it that way, even though we know with almost certainty that doing so is completely wrong. I think Carrol is doing the same thing here with causality and time.

    • OverlappingMagisteria

      I was gonna make the same analogy with the sun rising. Thanks for saving me the effort of writing it up.

    • Mike

      his defn seems to undercut his science. if causality is mind dependent and doesn't 'really' exist but only 'emerges' out of something changeless in our minds then maybe scientific experiments are dubious: true for thy but not for me?

      • OverlappingMagisteria

        No.. not mind dependent in that way. Try the sunrise analogy:

        Is it true for you, but not for me that the sun rises in the east? No.. it "rises" in the east for everyone... even though in reality it doesn't really rise. But we tend to think of it as rising for convenience.

        • Mike

          i don't get your point. are you saying that finding the cause of cancer doesn't mean that anything is actually causing it only that it appears to us that way?

          now our brains are part of the causal universe. do stimuli also not cause me to jump when i hear a very loud sound, i only experience it as a cause but it isn't?

          it's very strange to think of things like that. to be honest it defies all common sense.

          • David Nickol

            I was thinking about causality, and this scenario occurred to me. There is a city that has a patch of very bad weather for a couple of days, and the roads are icy. The number of traffic accidents for those two days is ten times the regular average. But it is found that there were no accidents at all involving cars that used chains or snow tires. So what is the "cause" of the higher accident rate? Is it icy roads? Or is it driving without chains or show tires? Or perhaps this took place in a town whose drivers are very unaccustomed to driving on icy roads, and the exact same conditions in a city with experienced winter drivers would have seen no spike in accidents. So what is the cause then. Icy roads, no snow tires and chains, or inexperienced winter drivers? And do we include as part of the cause that frozen water is slippery?

            That's just me thinking out loud. In any case, take a look at the Stanford Encyclopedia of Philosophy's entry titled The Metaphysics of Causation and see how much of it you understand. These are issues about which no simple statements can be made.

          • Mike

            to me it seems obvious that in every accident there would be a combo of causes but each accident wouldn't be w/o a cause.

    • Rob Abney

      Brian, does the same explanation you use for the sun rising also apply to a baseball causing a window to break? Is there something more fundamental that is occurring?

      • I would say so yes. This would be an outcome of the B-theory of time.

        • Rob Abney

          So did the baseball break the window or is that just an abstraction? If the ball did not actually break the window what actually happened?

          • If you are asking in terms of fundamental reality and b-theory is true, then these questions do not make any sense. They all presume A-theory of time.

          • Rob Abney

            You are probably correct that I assumed the A-theory but how do you explain it using the B-theory of time?

    • Ye Olde Statistician

      There's that "emergent" stuff again. Yet Carroll denied emergentism in his on-line discussion with Massimo Pigliucci, who is an emergentist. This is beginning to sound like having one's cake and eating it too, waving "emergent" around like waving one's hands, and crying "brute fact" when need be.

      But time is the measure of motion in changeable being. If there is no changeable being, there is no time. Or as Einstein once put it:

      Formerly, people thought that if matter disappeared from the universe, space and time would remain. Relativity declares that space and time would disappear with matter.
      Albert Einstein

      Augustine described it differently:

      With the motion of creatures, time began to run its course. It is idle to look for time before creation, as if time can be found before time.
      De genesi ad litteram, Book V, Ch. 5:12

      or more formally:

      [T]here are no objections of principle against the introduction of this hypothesis, by which space and time are deprived of the last trace of objective reality.
      -- Albert Einstein, "Explanation of the Movement of Mercury's Perihelion on the Basis of the General Theory of Relativity," 1915

      It is much nicer to call something emergent if we can describe the emergence rather than just wave our hands.

      It would also be nice if we could shake ourselves of the habit of confusing causation with a temporal sequence.

      • Will

        There's that "emergent" stuff again. Yet Carroll denied emergentism in his on-line discussion with Massimo Pigliucci, who is an emergentist. This is beginning to sound like having one's cake and eating it too, waving "emergent" around like waving one's hands, and crying "brute fact" when need be.

        Can you quote this "emergentism denial" you are talking about. Carroll has an entire section of the book dedicated to it and emergence is required to understand the connection between the microscopic and macroscopic. He says emergence is often misused, so perhaps he thinks Pigliucci is misusing it. Anyone it will be very helpful for you to source your claim, as I know for a fact that Carroll does NOT reject all emergence, even though you keep saying he does.

        • Ye Olde Statistician

          It's in the comm box at this link:
          http://rationallyspeaking.blogspot.com/2012/10/essays-on-emergence-part-i.html
          But you will have to hunt for the comments by Carroll and the responses by Pigliucci. Now, Carroll may want to have his cake and eat it too, but Pigliucci keeps after the logical entailments of Carroll's statements.

          • Will

            Let me quote:

            Massimo, thanks for the plug for the workshop. I haven't read Batterman's paper, but from your quotes above I suspect I would be tearing my hair out in frustration if I did. In particular, to claim that a phenomenon is emergent "if its behavior is not predictable given full knowledge of the behaviors of its parts, and if it is somehow new — most typically this is taken to mean that emergent phenomenon displays causal powers not displayed by any of its parts" seems unnecessarily contentious, and exactly why these discussions crash and burn almost immediately.

            If you believe in atoms and the laws of physics, the behavior of a gas of particles certainly *is* predictable given full knowledge of the behaviors of its parts, *in principle.* In practice, of course, it's hopeless, and it's much more sensible to use the renormalization group (or its moral equivalent) to talk about effective theories of thermodynamics and phase transitions etc. That setup is more than enough to have extremely interesting and productive conversations about reduction and emergence, without invoking new "causal powers" that seem incompatible with the straightforward mathematics.

            "And what principle would that be? You are making an entirely unwarranted metaphysical assumption here, which you cannot actually back up epistemically."

            I'm assuming the validity of Newton's laws of motion. Or the Schrodinger equation, if you want to do quantum mechanics. Seems like pretty non-slippery ground to me! Of course we don't know the ultimate true laws of physics, but if that's the only claim being made, it would be useful to just say that.

            I don't know what it would mean to "derived physical reductionism," nor do I think that qualitatively new emergent behavior is absent from Newton's laws (depending on definitions). The point is simply that Newton's laws, applied to a set of particles, gives you a closed set of equations. With appropriate initial conditions, the solutions are unique. There is no room for additional causal influence. The equations give unique answers; you can't get a different answer without violating the equations.

            There is an important and interesting discussion to be had about emergence, and it has nothing to do with being unable to predict behavior from component parts, nor with new "causal powers."

            I see nothing that contradicts weak emergence, though he is quite skeptical about strong emergence. If you are unfamiliar with the difference between strong and weak emergence, this article is useful.

            http://www.iep.utm.edu/emergenc/#SSH2ai

            Just fyi, I don't think Carroll believes that causation is emergent, it's just a useful story. A useful story != emergent. The rules of baseball are useful, but not emergent per se. Are useful stories real? Is baseball real? It depends on how you define real...

      • You might want to modify your discussion of emergence to castigate 'weak emergence', which does not have some of the key properties of 'strong emergence'. One way to think of this difference is to consider whether 'rationality' is a real thing, or just a sort of approximation of ultimately impersonal forces doing their truth-agnostic thing. Only on strong emergence can 'rationality' be a real thing, with real causal powers.

      • Looks like you simply want to refute B-theory of time.

        I don't know if A or B theory is correct. The last time I looked into it it seemed scientists and philosophers were not in agreement.

        I do not subscribe to the B-theory of time. But the point here is not which one is correct. The point is, if B-theory is correct, we need not stop speaking, or even thinking of of time as chronological in many, if not most circumstances. Just like it is fine to speak of, and even think of, the sun rising even though we know this is false.

        • The point is, if B-theory is correct, we need not stop speaking, or even thinking of of time as chronological in many, if not most circumstances. Just like it is fine to speak of, and even think of, the sun rising even though we know this is false.

          It's not at all clear that this is true. For example, in the book Against Moral Responsibility, Bruce Waller argues that accepting a compatibilist notion of free will entails great changes in how we think of 'moral responsibility'—so much so, that the replacement concept is very different from what is commonly thought of as 'moral responsibility'. Why not the same with time?

          • I do not see the connection of time to free will. In any event I agree A or B theory of time is not established in physics or philosophy. I have really no idea.

            Certainly our intuition about time favours A-theory. But it also favours time being constant, which we know is not the case.

            Whatever time really is, it is not what our intuition thinks it is.

          • I do not see the connection of time to free will.

            You appear to be working with the following principle:

            (X) Even if P is not strictly accurate, we can go on using it in non-scientific discourse.

            There are three values of P we can work with:

                 (1) time according to the A-theory
                 (2) speaking of the sun as 'rising'
                 (3) moral responsibility via libertarian free will

            You have argued that (X) applies to (2), therefore (X) applies to (1). I have pointed out that (X) may not apply to (3), and therefore it may not apply to (1).

          • Ok, I get it. You are assuming that if I am a determinist I do not think there is any real thing of moral responsibility, but it makes sense to speak of moral responsibility.

            This is not my view. I basically would say that morality generally is not fundamental in any way but is a function of fundamental things (matter/energy). It is conceptual, but not always abstract.

            However, this has nothing to do with free will or determinism. I hold this view irrespective which position I take on free will.

          • Ok, I get it. You are assuming that if I am a determinist I do not think there is any real thing of moral responsibility, but it makes sense to speak of moral responsibility.

            No. Bruce Waller's argument in Against Moral Responsibility is that the scientific correction to our understanding of human action radically changes how we should think of morality. The change in understanding at a lower level radically changes how we should think of the higher level, at least according to Waller. Given this, I don't think we can naively assume that on other topics, radical changes in how we think of the lower level can be assumed to have no effect on a higher level. Indeed, exactly to the extent that there is "no effect", reductionism seems false.

  • David Nickol

    Is the Passage of Time Real or Just an Illusion?

    Sean Carroll not only says it is real, but in the very helpful video provided by William Davis, says the following:

    The best theories we have of reality right now do include the notion of time in them. It is not an illusion. It is not emergent. It is not a fake. It is really there. It is one of the fundamental things that we need. So the question is, once we finally understand everything, will we have a better theory of everything in which time disappears? And opinions differ. My personal belief is that time is actually going to survive. That once we understand the best possible theory of nature, time will be a big part of it.

  • neil_pogi

    Time is immaterial..

  • TomD123

    I know this is an old post, but I think it is worth putting out there an important argument (and I think decisive) against presentism (associated with A-theory).

    1. If Presentism is true, there is no fact of the matter regarding statements about the past

    2. There is a fact of the matter regarding statements about the past

    3. Therefore, presentism is not true.

    (2) is obvious. So that leaves a defense of 1. Well here is the argument: Suppose presentism is true. In that case, only the present exists.

    Now, suppose that I claim that yesterday, the universe was created out of nothing by God (or an evil demon or a special alien or an unintelligent causal process, etc.) and in this creation the universe was made with the exact properties that you observe now. For instance, we were created with memories from years ago, the universe was created with textbooks reporting past incidents and an earth with an apparently old age, etc.

    The problem with presentism is this: There is no way in principle that could justify objecting to my claim above. The problem is not merely we cannot ascertain why the claim is false, rather, the problem is that there is nothing in principle which could justify anyone objecting to my claim.

    Take an analogy: if I claim that the earth is flat, you can object to my claim by appealing to the roundness of the actual earth. Even if you do not personally have the means to show that the earth is round, and in fact, even if you do not know the earth is round, in principle, it is possible that my claim turn out false because there is in fact a round earth.

    But what can the presentist say of the past? There is nothing analogous to the actual round earth to which the presentist can point and say "see, the earth wasn't created yesterday!" The presentist cannot appeal to anything of the past because she claims it does not exist. Nor can the presentist appeal to anything in the present because in my claim, I stipulated that the creation mechanism left the world exactly as is. In other words, both my claim and anyone else's are equally compatible with all of the data in reality.

  • neil_pogi

    if time is just an illusion, then atheists should abandon the 'billion years' time frame for the universe and so on. because of his hatredness of God, every thing under theism should be elimiated without even thinking of the consequences to other atheists' treasured theories.

  • Mikahel

    instead to answer to any part of those theories I prefer to create a further question, that may bring on one of this two theories.
    do we live any single second, any single tenth, hundredth, thousandth of second...and so on, of that life?
    If the answer is yes, you should try to define how long is the time between one second and the following one... you may find that is an infinite time.
    So the answer that appear more logic to my question is that we living the life jumping from one event to another where the time is calculated by whatching the clock during those events.
    So is this theory A or B or even C (an illusion that must be taken as reality, like a dream is a dream only when you wake up from it)?