No, your tense is wrong. Do, not did. What I did yesterday existed, it impacted the present, but it no longer exists. The effects are still felt. — Hanover

Indeed, indeed!

Cool. So there could be no passage of time in a void. Picking a point in time is actually picking an event. The assignment of a temporal point says something about how our event is related to other events. Is that about all we can glean from Leibniz? — Mongrel

I don't know; I'm not familiar enough with Leibniz's metaphysics.

I wouldn't go as far as saying that picking a point in time is actually picking an event. (I assume you mean "event" to refer to something more substantive than what physicists call events: i.e. mere space-time points). But it does require there being a substantive framework (e.g. an actual set or rulers and clocks) relative to which temporal (as well as spatial) locations are defined.

Did we agree or disagree that Leibniz's argument for relative space works for relative time? — Mongrel

Yes, if what is being denied under the label "relative time" is the intelligibility of the idea of an absolute positioning of events in time, then the argument against the idea of an absolute positioning of events in space works just the same for time, it seems to me.

In the early, radiation-dominated universe gravitational collapse could not occur (because reasons). — SophistiCat

I assume you mean "(regional) gravitational collapse(s)" and not global collapse.

The universe then was close to a (local) thermodynamic equilibrium. If global expansion did not occur and the macro-state of the early universe persisted indefinitely, it would have remained a very uniform, hot "particle soup". The entropy then was close to its maximum value - which is why it seemed weird to me to characterize that state as "perfect order".

Yes. The maximum entropy of a system isn't supervenient on its actual macro- and micro-physical states but also on the boundary conditions since those conditions contribute to determining the number of micro-states that are available to the system.

But then, characterizing entropy in terms of order is generally misleading.

Following rapid non-equilibrium expansion and cooling additional entropy was created first by nucleogenesis and later by gravitational collapse.

This is rather akin to the emegence of systems characterized by new kinds of entities that enjoy newly created low-energy degrees of freedom as a result of phase-transition (in the direction of lower enthalpy; e.g. recombination, condensation, freezing, etc.) or the emergence of systems characterized by effective field theories. What is created insn't entropy, since those global/regional transitions are thermodynamically reversible (since adiabatic), but rather new "opportunities" for newly created entities (e.g. dissipative structures) to persist in time through thermalizing the high energy radiation that was created (together with the new cold sinks) by the transition process.

Under the worm-theory, those experiences of being at my computer are had as part of a larger experience which includes other times. — Mr Bee

I am not sure why the worm theorist ought to be committed to that. She is committed to the temporal stages of a person being parts of that person. Those stages add up mereologically to a worm and the person is numerically identical with this worm. But it doesn't follow that experiences had by that person at different stages make up a unified experience. Likewise, my organs and limbs are part of me. But it doesn't follow that my organs are part of a unique super-organ or that my limbs are part of a super-limb. It is the stages of the subject of the experiences that are parts of the whole person (i.e. worm) according to worm theory, not necessarily the experiences themselves.

Here is another way to put the point. Having an experience is tantamount to one being in cognitive contact with some determinate aspect of one's perceptible environment (in such a way that the elements of this experiences display a synthetic unity). This is similar to one being in physical contact with a material object. One can be in contact with different objects at different times. The worm theorist is committed to the idea that she is ('now'-ontologically) in contact with all the objects her different stages have been (are, and will be) in contact with. But she is not at all committed to the idea of there being a unique object that is the mereological sum of all the objects she, as a worm, is in contact with. All of those commitments (and lack thereof) are justified by her conception of continuants and her theory of time, and are quite independent of whatever is available to her through introspection at various times.

Are those other times which have those experiences a part of me right NOW? If not, then they don't count.

Under the worm theory, they should be a part of me NOW (since they exist), so so much as I am talking about my total experiences, it should, assuming the worm theory, include experiences of all these times. — Mr Bee

According to worm theory, those future and past experiences would be experiences had by stages of yourself that are part or you now in the ontological sense of "now". They are not experiences had by you now in the ordinary sense of "now" (i.e. the temporal location sense of "now"). Let us use "now-o" (ontological) and now-tl (temporal location) to disambiguate those two senses as distinguished by the eternalist theorist. Provided that you don't equivocate between those two senses, then it seems that P3 asserts that you are not experiencing anything other than sitting at your computer now-tl. But it doesn't follow from this introspectible fact that you aren't experiencing other things now-o. In fact, you are experiencing now-o everything that you experienced in the past or will experience in the future, according to the worm theorist. Of course, you can not know this on the basis of your introspective experience now-tl alone. But you can know it on the basis of your reflection on the meaning of "now-o", your memory of your own past experiences, and your expectations regarding your own future experiences.

What you call "opposite" often is called "contrary". Contrariety and contradiction are two sorts of opposition. Look up Aristotle's Square of Opposition. (Also on the SEP)

I'm into J J Gibson's 'ecological approach' at the moment. He argues that his approach is non-dualistic and even makes playful reference to ecological physics. This is on the basis that for an animal to perceive an object is for it to see the 'affordances' available from the object, i.e. the natural world is a vast network of mutual relations of affordance, an approach derived from gestalt psychology. — mcdoodle

Did you read The Ecological Approach to Visual Perception? Gibson is the most philosophical of all the psychologists. My understanding of Aristotle's metaphysics, of Kant's epistemology, and of the inseparability of practical and theoretical reason, are conditioned by Gibson's concept of an affordance.

Maybe it is, but even so, I am still not sure why you think that is. Let me repeat once more the version of P3. that I have been proposing:

P3. I find that I am only experiencing sitting in my room during the temporal duration in which I exist. (This is what I find through introspection upon my direct experience) — Mr Bee

But this seems prima facie false, assuming only that your existence extends both to the past and to the future (or even, only to the past). It only appears true under the assumption that your own existence is restricted to the duration of your present experience. But this assumption seems to build stage theory onto your premise P3. (Or, more precisely, it builds into P3 a feature of stage theory that distinguishes it from worm theory).

what is your opinion on the cosmological arrow of time in relation to inflationary theories; I lean more towards Guth' model and his model rests mostly on the physics of scalar fields. — TimeLine

This model makes much sense to me, but I am not in a position to assess it against competitors. (In fact, I don't even know what the viable competitors might be. When I was studying physics, I attended a graduate seminar in cosmology given by Hubert Reeves, but that was more than 20 years ago and I didn't consolidate that learning. So you must be much more knowledgeable than I am)

Are you talking about the star itself or the stellar region? The entropy lost by the star is certainly not at an equal sum to what it gains by its surrounding, so you would need to further elucidate this point. — TimeLine

First, apologies, when I said "when the temperature of the newborn star is lost...", I meant "heat" not "temperature". I was picturing the temperature of the star and the temperature of interstellar space evening out.

I can make my point a little more precise through breaking up the process in two stages (i.e. two merely notional stages, because they normally overlap). In the first stage, gravitational instabilities are magnified into local gravitational collapses of large clouds of gases. Under the effect of self-gravity, those clouds heat up adiabatically. Adiabatic compression is a thermodynamically reversible process and so doesn't give rise to any entropy change within the collapsing gas masses (neglecting chemical or nuclear reactions). But then, in the second stage, the nascent stars (or hot gas clouds) begin radiating heat away to the comparatively colder space between them. It is this temperature inhomogeneity that can be harnessed to produce useful work (as indeed life on Earth makes use of). The process involved in this second stage isn't reversible since, as you note, more entropy is generated by the production of low energy photons (the warming up of cold space) than is lost to the cooling down of the stars.

"Let's assume" was an example to make things easier to understand. That was not my view or built into my P3. I am willing to assume in my OP that our existence can be any duration of time, whatever it happens to be. — Mr Bee

Yes, that might have been your intent in the original post of this thread. (Your argument, back then, seemed to hinge on something like the synthetic unity of experience). But, just now, you had offered this as an explanation (for The Great Whatever) as to why you only are experiencing sitting at your computer, while excluding other experiences had at earlier or later times in your life. You also meant to insist that your intention wasn't simply to restrict reference to what you are experiencing now, but rather to what you are experiencing while you exist. This argument, which doesn't appeal to the idea of synthetic unity of experience anymore, now seems to hinge on a restriction of the temporal scope of your existence. And this is what distinguishes stage theory from worm theory.

Where did I assume that? Can you quote the phrase? — Mr Bee

"Let's say that the entire duration in which I exist is limited to an instant."

Have you even read my post? I literally just explained how in the paragraph above it. — Mr Bee

In this paragraph you enjoin us to assume that the existence of the experiencing subject is restricted to a moment in time. This is an assumption that distinguishes stage theory from worm theory. If this assumption is thus built into your premise P3, that would make your argument in favor of stage theory circular.

Yeah, the universe had better begin with a low(er) entropy, but I don't know if I would call a homogeneous gas a "perfect order". — SophistiCat

Yes, this sounds a bit paradoxical when one is used to consider examples of low and high entropy restricted to systems that aren't dominated by gravity. Gases and liquids in closed boxes, for instance, display maximum entropy in homogeneous states. Yet, for gravitational systems characterized by a universal attractive force between the components, the opposite is true.

Think about the measure of entropy as the opposite of the measure of energy-available-for-work. In a vast cloud of gas (or individual stars) that is homogeneously distributed in space, gravitational instabilities can give rise to local gravitational collapses in which things heat up. This creates spatial varations in temperature that can be used for producing work. As the temperature of the newborn stars is lost to cold space, usable energy goes down and entropy goes up. The reverse process -- the "re-homogenization" of those stars and galaxies would require external work. Usable energy would go up and entropy down. (This can also be explained through the standard statistical mechanical definition of entropy as the logarithm of the number of micro-physical configurations. Counterintuitively, it so happens that gravitational systems have more spatially inhomogeneous states available to them than homogeneous ones. This is an interesting fact to reflect about.)

I have proposed an alternative conception of "now", describing the "temporal region in which I exist" as a better description of what I would mean when I would have to use the word now. I even gave an analogy involving our use of "here" to support it. After all, "here" simply specifies my location, not that of the utterance, and it seems like "now" should similarly specify the location in time, not of the utterance, but of myself, whatever that may be. — Mr Bee

I would have thought that "here" refers to the location of the speaker at the time of utterance. (This is how, at any rate, I would make explicit what the reference of "here" is, in particular occasions of its use, without this being meant as an explanation of its Fregean sense.)

For instance, Sue could be teaching Max how to tidy up the workshop. She tells him: "Go fetch the hammer over there and bring it back here". Then, she accompanies him to the place where the hammer is. It would then be odd for Max to insist that the hammer now is located where Sue wanted it to be on the ground that "here" refers to the place Sue (now) is standing. Of course, if both Sue and Max are stage theorists (and not just armchair stage theorists, but people who strive to live up to stage theory in everyday talk) then they may want to reform the way in which they use indexicals. In that case Max's later counterpart may take himself to be committed to obey the instruction that had been given by Sue's younger counterpart to Max's younger counterpart. In light of Luke's earlier suggestion in this thread, this may be seen as a way of construing the semantics of indexicals that attempts to retain the dynamicism of ordinary presentism within a 4-dimensionalist framework. (Incidentally, Gareth Evans's neo-Fregean account of enduring thoughts that can be re-expressed at successive times without loss of meaning with the use of inter-related classes of demonstratives or indexicals (e.g., "here" and "there"; or "yesterday", "today", "tomorrow"...) characterize such thought as dynamic thoughts).

Apparently that didn't sit well with you because that is not what the word "now", as commonly construed in our everyday language, is used. Technically, under something like a layman presentist framework, the word "now" can refer to both the time in which I exist and the time of the utterance, but that is certainly not true under something the worm view (or really any view that allows for a temporally extended experience). If this type of view isn't satisfactory to you then I will probably need more of an argument to be convinced.

If ordinary language is to retain a pragmatic use (and some of its meaningfulness) as interpreted within a stage theoretical framework, then, although indexicals may be taken to make no (direct) tacit reference to the time of the utterance, they would still have to make tacit reference to the specific stage of the individual to whom later stages of this individuals (and of other people) are referring back to while interpreting the original utterance. This still seems to amount to making a tacit (albeit indirect) reference to the time of utterance. To completely give up on such tacit references to past and future times would lead to the disintegration of 'dynamic thoughts' and the narrowing down of experience (and of the acts of reference therein) to a narrow Cartesian space of private sense data, it seems to me.

I don’t fully comprehend the distinction between stage theory and worm theory, but they are both consistent with a 4-D block universe, and a 4-D block universe is consistent with a static, motionless universe. Endurantism, on the other hand, is consistent with a 3-D dynamic (presentist) universe. I believe that the perdurantist “stage theory” is an attempt to incorporate some dynamic aspect into the static 4-D block universe, but I consider these to be irreconcilable.

... — Luke

This strikes me as a very sharp diagnosis of the motivation of the stage theory.

Like I told Pierre, when I say that I find myself as only having the experience of, say, me sitting in my room, I am not saying that I am having them "at a time". Nowhere does such a notion come into my description of what I am experiencing. I only say that I am only having this experience in a general sense. — Mr Bee

But this is just to say that the time at which you are having an experience doesn't figure explicitly as part of the content of this experience. You can distinguish, though, right now, between your relating to experiences had by you in the past, in the present, or in the future. You can say, and believe: "I saw my friend earlier"; "I am seeing my friend now" and "I will see my friend later". In those forms of expression the words "earlier", "now", and "later" function as indexicals. The times that they refer to are functions of the time when the expressions are being uttered. (Likewise, the word "I" can refer to you by dint of the fact that it is being used by you; and the word "here" refers to a specific place by dint of its being uttered by someone located at that place.)

When you are enjoying the visual experience a tree, you need not be thinking of this experience under a mode of presentation (i.e. a Fregean sense) that could be expressed thus: "I am seeing this tree at 4:16 PM on April 10th 2017". You could also be expressing the same content under the different mode "I am seeing this tree now", which is equivalent to the content of "I am seeing a tree". In the latter form of expression, the temporal reference of the expression "now" is tacitly encoded into the tense of the verb "seeing" (together with the progressive aspect). It thus has the same Fregean sense. You can't really have a visual experience while being agnostic regarding the time when you are having it (i.e. regarding its being either present, past or future). If you are doubting whether an experience is a present visual experience or a fuzzy memory, for instance, then you are doubting its very status as an experience as opposed to its being a product of your imagination, say.

I, as the entity that should be a temporally extended conscious subject, only have an experience of sitting in my room in front of my computer simpliciter. This is just how it feels to me. — Mr Bee

Yes, and the worm theorist need not dispute that. But then, at a later time, you go out and see a tree in the garden. You are having another experience with a different content. The worm theorist says that those two events relate you, the very same individual (or space-time worm) to the two separate contents of those experiences. But just because the same individual is thus related to two separate experience contents doesn't contradict the fact that, as part of the form of those very experiences, you are picturing yourself as having them in isolation (in the "present time" when you are having them). All this goes on to show, from the point of view of the worm theorist, is that the different segments of the "worm" are, indeed distinctive parts of that worm with distinguishable properties.

So because your degree is bigger (or something else for that matter) than mine, you think you automatically know more than me? — dclements

I think Ernestm was merely paying you a compliment.

My objection to this theory is that it sure as hell seems like I have thoughts that change over time and not that I'm stuck in my single thought. The concept of change seems impossible under an eternalist theory because there is no becoming, just existing. — Hanover

I quite agree. But I think both the views of endurantism (closely associated with stage-theory) and perdurantism (closely associated with eternalism or 4-dimensionalism) make it hard to account for the metaphysics of change. I used to be committed to endurantism, myself, but Sebastian Rödl (see his Categories of the Temporal, HUP, 2012) made me realize that everything that the perdurantist may want to say can be translated without loss in the language of the endurantist, and vice versa. What is really missing to both from those view about time, objects and predication, is the Aristotelian concept of a substance.

On edit: contrary to what I said above, stage-theory is more commonly viewed as a variety of perdurantism. This makes sense, since endurantism entails that when a "stage" is present, then the whole objects is present, although its past "stages" don't exist anymore, and its future "stages" don't exist yet. Hence, worm theory and stage theory are two varieties of perdurantism.

It seems that this type of response collapses to the stage theory does it not? Cause if we are going to grant that there are multiple different conscious subjects who exist at every stage of our lives anyways, then why not just adopt the stage view? — Mr Bee

That's because the eternalists (or the perdurantists) aren't saying that there are different conscious subjects along your world-line. You are the whole worm, and your temporal time-slices are temporal parts of yourself just as much as your hands and feet (or rather, their own worms), say, are "spatial parts" of yourself. What the eternalist may argue is that your having experiences one at a time doesn't contradict your being a worm who is having those experiences anymore that your being touched by someone on specific parts of your body, say, contradicts that it is you, the same individual, who is being touched in each case.

As far as I know, the worm theory claims that there is one only entity, one conscious subject which identifies with the whole spacetime worm.

Agreed.

Although it is conceivable to argue that such a being could also exist on top of the multiple conscious subjects at every time it would seem unnecessary to do so.

Agreed. The defense that I mustered on behalf of the eternalist doesn't need that.

Welcome to the forum!

...So here is my argument in a nutshell against the worm view:

P1. The worm theory requires that we are temporally extended beings.
P2. If we are temporally extended beings, then we must have all of our experiences at every time in which we exist together*.
P3. Our experience is limited to only one time.
____________________________
C. The worm theory is false.

* Note that by saying that I should have all of my experiences "together", I do not mean that we have all of our experiences "at once" as in "at a time". Our experience can extend across multiple times, just as much as our bodily experiences at a single time is spatially extended (I see through my eyes and feel through the nerves in my body for example). The point is that we have them all. — Mr Bee

This note is indeed an important concession for you to make to the proponent of the worm-view, (which is a view about identity also called perdurantism). But its seems to me that it is hard to make consistent with your defense of P3. (See below)

The support for P3. is simply based upon introspection about our direct experience. My judgement I am not experiencing any other times shouldn't be illusory any more than my judgement that I am not in excruciating pain, or that I my judgement that I am having a red experience, which I take to be pretty certain. For me, I find that my experiences are only limited to me sitting here typing up this post at this time and nothing else, and I believe that a similar finding would hold for you too. This experience of me sitting in my room in front of my computer is not had as part of any other experience or together with other experiences at other times. — Mr Bee

I think the worm-theorist would readily accept the way you are characterizing the content of your experience (i.e. what it is you are experiencing) but she would question your portrayal of what it is to be the subject of a singular experience. The worm-theorist would claim that each separate content of experience had by you over time is being had (which denotes a singular event rather than an ownership relation) not by "your" perduring worm as a whole, but rather by just the one contemporaneous temporal stage of your worm that is occurring at the time when this experience is being had. Hence, the fact that you (the whole worm) are truly only experiencing one thing at a time just reflects the fact that those episodes (or events) of experiencing something or other characterize your own temporal stages separately. In yet other words, your saying that you only experience one thing at a given time only boils down to saying that only one single temporal stage of yourself (i.e. just one time-slice of yourself) is involved directly in this experiencing. (There may still be indirect involvement through the exercise of memory and anticipation).

Is it that there were more photons released from dense regions because they contained more photons? Did the gravitational strength differential of these more dense regions cause more photons to be emanate from specific trajectories at the time of decoupling? — VagabondSpectre

As far as I know, the acoustic oscillations are a result of gravitational instabilities. Once this is accepted, you don't need a further mechanism to explain why there are more photons coming from the denser regions. If there are more atoms recombining in a given volume of space, then, of course, there are going to be more photons being emitted from that volume.

It is certainly one of the more mystical aspects of Wittgensteinian thought, and does take some time to grasp. Reading the tractatus, red book, and blue book is helpful. — ernestm

Those would be the Blue and Brown Books. The Red one is from Chairman Mao ;-)

There is a fundamental difference between the sort of reasoning exemplified by these Vedic philosophers - or for that matter by ancient atomists - and later scientific models like quantum physics (or atomic physics). The former is a priori reasoning, motivated by abstract (pseudo-)puzzles. It bears no relation to the motivations behind the later scientific models, and any resemblances between the two are accidental and superficial. — SophistiCat

Many of the puzzles, as well as many of the insights, were real, it seems to me. There are both deep differences and deep similarities. If you read the intellectual biographical recollections of Heisenberg (or Schrödinger, or Einstein) you'll find that there are lots of philosophical and other a priori considerations that grounded their theoretical innovations. Of course there is a sort of interplay between theory and experiment that rests on the practice of the mathematical formalization of the laws of physics (and of the laws of some other special sciences) and the derivation of precisely quantifiable predictions (and explanations) that wasn't developed until recent centuries. This profound difference doesn't negate the profound similarities.

You asked what time could be reversed relative to. — tom

Maybe someone else, not me. I didn't touch on the issue of the arrow of time. I was only considering the intelligibility of the idea of shifting the temporal scale (or all events) four hours in the past (or in the future), in analogy with the idea of a uniform translation of space itself.

The possibility that time and space are limitless is confusing me. But is that a problem? Can the thought experiment just say that for every E, E happens 4 hours earlier? And not address whether time is finite or infinite? — Mongrel

The same question arises. Relative to what is everything happening four hours earlier? You have to imagine some undetectable framework of time (rather in the way one might want to picture empty space, metaphorically, as an empty stage) relative to which events are dated extrinsically. But if that's the case, then there would have occurred a shift in the time of occurrence of all the empirical events, all right. But time itself would not have shifted since it would have been externalized, as it were, to this inobservable framework.

Let us get back to the space analogy. We could imagine "space itself" being externalized in a manner somewhat analogous to the luminiferous aether of pre-relativistic physics; with the proviso that such an aether would be physically undetectable in principle. Can then everything in the universe be conceivably shifted 100 feet in one determinate direction? This can be conceived. But you still would not have shifted space itself, since on that account, space would have been externalized. It has been identified with the absolute spatial "positions" of the aether "stage". And this aether still would not have moved. If you were to imagine that the aether (space itself) also moved, then that must be a movement relative to some external spatial framework. You need another aether to identify "space itself" with. You are led to an infinite regress.

The entropy of the visible universe for example. — tom

Well, I was assuming all the micro-physical "events" to be shifted as well, not just the macroscopic ones. Since the entropy of a physical system supervenes on its micro-physical state, then the entropy of all the systems (including local cosmic background radiation) would be shifted back in time by the same amount.

Trying to adapt the thought experiment to address time is a little confusing to me. — Mongrel

Can't you ask essentially the same question about time? Anything that occurs (e.g. the construction of a house) could have occurred four years earlier (or later). But could everything that is occurring (and occurred, and will occur) in the whole universe occur four years earlier? Relative to what event would everything have occurred four years earlier?

Hi! What would you say truth is? Doesn't it presuppose truth to say what truth is? If this is so, is it bad? — mew

I'll only comment on your last two questions. If what you seek to achieve is an explanation, or philosophical elucidation, of the concept of truth, then circularity isn't necessarily bad. You can start with the concept of truth as you understand it, and then proceed to analyse it by means of the examination of a variety of practical contexts where the concept is normally used. Circularity only is bad in deductive proofs, or demonstrations. In that case it is a fallacy. You can't assume what you intend to prove as a premise of your demonstration. In informal contexts of discussion, this is also called begging the question.

But where explanations are concerned, Wittgenstein has suggested that circularity only is bad when the circle is too small, and hence uninformative. So, the trouble with some circular explanations isn't the circularity itself but the excessive simplicity: such simplistic, quasi-tautological, explanations aren't sensitive enough to all the relevant aspects of the use of the concept one wishes to elucidate. The solution to this problem is to widen the circle of inter-related concepts one appeals to. Peter Strawson called this (wide) circular method of philosophical analysis "connective analysis" (which could be contrasted with reductive analysis). In epistemology, Clark Glymour has devised a convincing explanation of the somewhat circular nature of empirical evidence for scientific theories. It's called the bootstrapping theory of confirmation. It's a good way to account for the essential theory-ladenness of empirical concepts: your evidence always is couched in terms that presuppose some aspects of the theory you are attempting to confirm by means of scientific experiment or data gathering.

↪VagabondSpectre (Y) — Mongrel

(Y) (Y)

Yes. Do you see a problem? — Mongrel

That would seem to be the same problem afflicting the idea of displacing the whole of space. You can shift a house 100 feet to the North. Can you move the whole of space in the same direction? What would such a hypothetical displacement be relative to?

Well. That surprises me. I thought the reasoning interesting and the similarity obvious. But as it is not on the point of this topic I will not digress. — ernestm

Yes, this issue may not be exactly on the point of this thread. But I agree with you that the reasoning is both interesting and relevant to features of quantum mechanics that bridge metaphysics and epistemology. I had mentioned earlier (I think in this thread) some similar reasoning that had put Heisenberg on the right path for the developments of his early formulation of QM (matrix mechanics). He explained his thought process in The Physicist's Conception of Nature.

Regarding the quality of the reasoning, there might be some obscurity in the argument, but those old Vedic philosophers don't strike me as being as being any less insightful than the early Greek atomists were.

an example of a non-sequitur is this: — Frederick KOH

I agree that it is a non sequitur! It is Weinberg's non-sequitur. It is a non sequitur because there actually are lots of reasonable explanations why some specific laws within some theories obtain that aren't reductive explanations in Weinberg's sense.

There is no scientific theory that does that! — Frederick KOH

Which is precisely why you must seek some deeper reduction base -- a more "fundamental" theory -- in order to disclose at least one of the multiple "arrows of explanation" the alleged convergence of which ground Weinberg's grand reductionism. Weinberg's "arrows" always point from one law or principle of a theory to laws or principles from another theory. Else, in his view, the first theory (and its laws) would be freestanding and grand reductionism would fail.

I am beginning to think that I will have to use the same reasoning as the proverbial judge who had to rule on what pornography is. — Frederick KOH

The Maxwell equations don't constitute a reduction of the four laws that you mentioned in anything like Weinberg's sense of reduction. That's because, for Weinberg, reducing a law (or scientific principle) consists in explaining why this law (or principle) obtains in terms of a more fundamental theory. The Maxwell equations formalize the laws of electromagnetism in a precise and consistent manner. They don't explain why those laws are valid. As I reminded you -- and you ignored again -- that is precisely why Weinberg seeks to reduce QED (the quantum mechanical version of electrodynamics) to another higher-energy effective field theory such as QCD.

Thank you for bringing this up. This is because you seem to want to define your way out of any counter-argument. How else do I pin down what you mean when you use terms that I have never seen any philosopher of science use?

As an exercise to anyone else still reading this thread, google "autonomous law" and see what you get. — Frederick KOH

Steven Weinberg uses the phrase "autonomous law" in "Two Cheers for Reductionism", one of the two book chapters that you enjoined me to argue against and endeavored to defend. I also was quite careful in explaining how I was using the term, quite consistently with Weinberg's own use, to signify the irreducibility of such a law within a theory to laws and principles from some other more fundamental theory. The explanation why such autonomous laws obtain (answering Weinberg's "Why?" question) rather is to be found at the same level of theory. I first made use of the phrase in this thread in order to explain the idea of a merely partial autonomy from one theory to another; when you had seemed to think that the question of the reducibility (or autonomy) of a whole theory in relation to some other theorie(s) is an all or nothing matter.

Those concepts and setups exist prior to and motivate the theories in question. — Frederick KOH

It's not generally the case that the empirical concepts that figure in a theory already were in use prior to the development of the theory. This would be to forget the theory-ladenness of observation. The theoretical understanding of the laws of a theory, on the one side, and the understanding of the empirical objets, relations and properties that populate the ontology of this theory, on the other side, more often than not grow together. The concept of a gene didn't predate the discovery of Mendelean inheritance. The understanding of the concept of mass and of force weren't quite the same before and after the development of Newtonian mechanics (or before and after Einstein's special theory or relativity), etc.

And in the four laws I gave an example where what the material constituents were is not clear. Especially when we know the classical theory that came after. — Frederick KOH

Sure. In that case you can't achieve reduction through appealing to a more fundamental theory that regulates interactions between smaller material constituents. Weinberg's "why?" questions would still be the question why those laws are valid, assuming that they aren't themselves fundamental. If Weinberg's "grand reductionism" were correct, then there would exist a more fundamental theory -- a reduction base for it (i.e. a theory that is closer to Weinberg's unique "final theory") -- such that those laws are causally and/or deductively determined by it. Maxwell's equations don't constitute such a reduction base, since they merely express those very same laws in a consistent and rigorous manner. Maxwell's equations don't answer the question why they themselves are valid.

The most obvious candidate for a theory that would serve as an appropriate reduction base for classical electrodynamics, according to Weinberg himself, would be a high-energy theory such as QCD. QCD is thus a theory that he deems to figure on the path towards his dreamed of final theory, with a GUT theory, and a theory of quantum gravitation also figuring further down this path. Unfortunately, as I've argued, effective field theories that are valid at different energy scales don't appear to reduce one another.