The Second Law of thermodynamics states that "The entropy of a closed system cannot decrease over time."

What are the philosophical implications of this statement, especially wrt to theology and metaphysics?

  • 5
    Can you expand (in your question) on what you're looking for? Do you have some idea already of how the physical law might relate to theology or metaphysics? Right now, your question is too open-ended.
    – Mitch
    Aug 17 '11 at 16:13
  • how is this meta physics? It sounds like you could migrate this to physics. There are profound consequence of the second law regarding the type of behaviors we expect to see in nature, and their consequences in terms of dumping heat into outer space, but not much metaphysics at all that I can see.
    – Ron Maimon
    Apr 13 '12 at 22:44
  • 1
    One consequence is that philosophers must eat and drink to do philosophy. Or anything else.
    – gnasher729
    Jul 5 '16 at 23:06

10 Answers 10


I don't think there are many implications.

For theology, you're usually assuming that the system isn't closed. So the 2nd law doesn't apply.

If you want your metaphysics to be consistent with the second law, you are not allowed to assume something that would lead to less-than-zero entropy far in the past. You could decide that the universe is an adiabatic reversible process (entropy = constant), or that it approaches adiabatic reversibility as you go further back in time. You could postulate that there was some time in the past where the rules changed or things started. Or you could devise a scheme where the system isn't closed, or assume that it's infinite (i.e. you can in principle push your entropy away to infinity to have whatever local entropy you like). Since you only need at least one of these to be true for the 2nd law to not be problematic, you have a lot of wiggle room.

Thus, although the second law is an extremely important principle in physics, it's pretty inert philosophically.

  • How is it that metaphysics as a whole somehow assumes entropy=constant or whatever?
    – Mitch
    Aug 17 '11 at 16:12
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    @Mitch - I mean that if you want your metaphysics to not contradict the 2nd law of thermodynamics, you need to assume that at least one of the above conditions holds. It doesn't have to be the "entropy of the universe = constant" condition.
    – Rex Kerr
    Aug 17 '11 at 16:18
  • If so, that seems pretty important for metaphysic then. Can you elaborate on that inyour answer (or merge inyour comment to the answer)?
    – Mitch
    Aug 17 '11 at 17:06
  • It seems the real point here is that neither theology nor philosophy/metaphysics assume a closed system, thus the 2nd law doesn't apply.
    – Cody Gray
    Aug 19 '11 at 5:16
  • @Cody Gray - One may elect to work with a metaphysics that does assume a close system; hence my other answers. With theology, closedness is usually rejected from the outset.
    – Rex Kerr
    Aug 19 '11 at 14:22

Since by re-arranging your furniture or physically exerting any action you convert energy (you got from food) into work. The energy is the movement of the physical action.

Taking the 1st law of thermodynamics into account: energy can neither be created or destroyed you could also say it is continuously converted. The entropy as I understand it is the state of energy converted as work, so it can be concentrated (a bit like a dense bundle- or that extra strong shift of the heavy sofa) or scattered (like droplets or particles-re arranging the ornaments into position for example) which ever 'state' the energy remains the same expressed in work (concentrated on one big lift or scattered over duration across smaller items).

Any conversion as an action has a duration (time) and every action converts potential energy into work, increasing the entropy from the last action of conversion.

Applying this to humans (and theology is a human logos) you could interpret this that every action has a consequence between human beings. The action can be physical interaction and communication of information, opinion, ideas, concerns, etc...This would imply that humans all shape through the conversion of energy into work their world (natural and intangible) and I guess makes a case in theological and philosophical terms that the individual is a spec in the wider picture we call existence and 'reality'-and hence places responsibility onto each individual in being through action (existential philosophy: Heidegger on 'Dasein'.

The entropy in this case with an ever growing world population (and hence increasing conversion of existing energy into work) over time can only increase, which can be a bit disconcerting as it implies increase in diversity and quantity (difficult to control and bundle) some may call 'chaos' (Greek creation mythology: Chaos). On the other hand if you flip this the other way round and think what would therefore decrease entropy you come up with a nihilistic solution of self extinction we currently witness through the actions of terrorists.

Baring in mind that the potential energy released at the beginning of time which formed the Universe (and in a truly macroscopic system that started with scientifically called the 'Big Bang', or 'Chaos' in mythology, God as the creator in Christian believes, etc...), and eventually our planet, life, on the 1st law of thermodynamics will always remain the same and the system (the Universe, planet Earth) would not be any worse off just differently transitioning and manifesting- if we as a species are no longer around.

So this means that it is very much in our own interest to sustaining ourselves, others and our World. The increase of entropy is inevitable, we should not focus on wasting our energy on changing and controlling this energy but 'go with the flow', more akin to non material existence as encountered in Eastern Philosophies and Religions, such as Taoism and Buddhism, Hinduism- or to decrease-go back in time.

  • 1
    Welcome to Philosophy.SE! Some of your points are a bit hard to follow. Can you go through and edit this post to make things more clear? For example, I don't see how your first 4 paragraphs show that the 2nd law "means that it is very much in our own interest to [sustain] ourselves." I also don't see how a property of material existence argues that one should follow philosophies that have a non-material outlook to things. Aug 11 '15 at 21:36
  • Apologies for the hard to follow bit. My point in a nutshell is that rather than focusing on the outcome of actions-the product- which is Western philosophy is largely focused on I find Eastern Philosophies more in tune with what the laws of thermodynamics describe- the dynamics. I took the liberty to apply energy and connections to communication and relationships between humans, as I pondered the question posed about the implications of the 2nd law of thermodynamics in the context of theology and philosophy. Aug 12 '15 at 21:34
  • @StephdeRoemer you can edit your own answer to make it clearer. Also, if you can provide some more philosophical sources, the answer will be a better fit.
    – virmaior
    Aug 13 '15 at 7:46

A funny answer is to remark that living things have to keep lowering their entropy for them to live (thus giving at least the same counter part to somebody else). If they did not, then they would reach a state of equilibrium, and as we all know, life is clearly not an equilibrium state. This is quite surprising, because life is recent in the history of the universe, while second principle of thermodynamic make us want to believe that the universe is getting closer and closer to its global equilibrium state.

How comes then, that "complex life" as us took so many times to emerge, if second law seems to go against it? Well, quite simply: their must exist some place in the universe that contains all the entropy required for living being to be, and complex structures to emerge. What are these places? They are our famous black holes. Black holes are the biggest well of entropy in the universe, and they took times to emerge. This is why, even though the second law of the universe seems to imply that the universe is getting more and more smooth and structureless, the existence of black holes allows him to actually complexify, even to make life a sustainable state of existence.

Conclusion: the second law of thermodynamics is against life, but the existence of black hole is here to sustain it. So, are black hole also here to allow complex structures to emerge in the universe (even life), or is it just a coincidence?

  • This is a very intriguing answer - I love this stuff (+1). I seem to recall reading (in and informal setting) that the evolution of the very early universe created a lot of "primordial" black holes. Is this no longer considered to be the case? I ask because of your comment that black holes took "time to emerge".
    – nwr
    Sep 5 '15 at 18:52
  • @NickR: as far as I know, its highly sensitive to your models. Still, lots of black holes are "new", in the sense that they weren't primordial. I don't know yet, if there exist a credible estimation of their mass or relative mass compared to primordial ones tho
    – sure
    Sep 5 '15 at 19:40

While I find "Rex Kerr's" answer quite nice, clear, and a bit startling, it seems to apply to a "big box" picture of some sort of "completed" metaphysical system. I am not sure one could refute a metaphysics simply by inconsistency with the Second Law, since its meaning remains unclear. Even in physics, Boltzmann's equation seems more like a mathematical "truce" than an ontological clincher. Assuming there is a role in our metaphysics for some sort of temporal consciousness or "Sein und Zeit," etc., we have innumerable issues raised by the Second Law. These assume their most compelling form in Maxwell's Demon, which I believe even Maxwell presented as a puzzler dealing with the nature of "mind" or "mental work." I am not competent to assess the various models of the demon proposed over the years. But I believe the most intriguing, in relation to res cogitans, is the one offered by Landauer, in which the demon can indeed reverse entropy in its little world as long as it can keep "remembering" what it defines as order, even as that order changes. As long as it can still "tell the difference." The problem comes with memory storage, the demon's "historical" account, so to speak. At some point it must physically clear or erase its memory. And this, as Landauer shows, is what requires external energy, more energy than the demon's efforts can conserve. The vague resemblance between the demon and the transcendental subject is intriguing. So how exactly does this impact metaphysics? Um, I'll get back to you in a few years, if I can remember how.


For an extensive discussion, with extensive citations, of the cultural, philosophical, and religious implications of the Second Law, see the book Entropic Creation: Religious Contexts of Thermodynamics and Cosmology by Helge S. Kragh.


I have thought about this a lot, but I'm not entirely certain what I have to say is relevant. However, I view the 2nd law as a manifestation of the Edenic Curse of Genesis. To me, this implies both that it wasn't operational til the Fall and will cease operation again at some point relative to the creation of the "new" heavens and Earth.

My interest is in what physical laws would hold to make life practicable in the absence of the 2nd Law of Thermodynamics.


This means asking "what are the philosophical implications of the fact that energy tends to dissipate".

The second law, as such, isolated from the rest of physical laws, suggests that everything should dissipate quite fast, that no objects and matter should exist. If just this law is considered, isolated from the rest of natural behaviors, touching a wall should imply quickly (or instantly) converting the wall into dust and perhaps energy.

Such perspective is evidently a mistake, because walls do exist. Moreover, a closed system is something physically impossible. The problem of such approach, as a teacher used to say, is this:

Nature is essentially change, and according to our perception, such change has two forms: organization and dissipation (statism is just an ideal, a macrostate, something that is only provided by perception; states are mental interpretations, whilst nature is pure change). So:

  • Dissipation is described by the second law of thermodynamics. The second law can be read as "energy tends to dissipate" (see the formulae!). If nature would behave only according to the second law, everything would have already dissipated.
  • We don't know a rule that would describe organization. If we would reach such milestone, perhaps we would be able to create a living entity from scratch.

So, while some natural manifestations produce dissipation, others produce organization. Existence is the result of both. Given that we exist and that life tends to get more complex and sustainable, it would seem that nature features more organization than dissipation, but evidently, such is just an speculation.

Anyway, asking the philosophical implications of a rule isolated from the rest of natural behaviors, has no sense, is just like trying an interpretation of an incomplete equation, say, " E= ".


I'd say, resolving the Maxwell's Demon thought experiment, integrating the second law and the physical reality of information, makes substance dualism, and disembodied souls, impossible (but, substrate-independence is is still possible, for a way to think about souls)

Any eternally state must be impossible. If there are minds operating, there 8s change, and the system will become disordered over time. I've always foubd the Buddhist cosmology more compelling, that the hells are impermanent too, and the heavenly abodes.


A lot of the implications one draws from this are going to depend on one's underlying metaphysical assumptions, and how one defines the key terms "entropy" and "information".

The Second Law, as you state it, is trivially false; if I take my living room to be a closed system, I can decrease the entropy there by organizing things and imposing order. In fact, viewed this way, humanity represents (in a metaphysical or theological manner) the pinnacle of the negentropic principle.

For this reason, most scientific views of thermodynamics tend to focus on the microscopic dispersion of energy, and not effects at the macroscopic level.

  • 4
    Decent answer, but firstly, your room is not a closed system (you cannot just define a system to be closed, it has to actually be isolated from energy exchange from the rest of the universe, at least to a good approximation), and secondly, since you can't isolate the objects in your room from the states of the molecules making them up, the entropy includes all the microscopic entropy by construction. So, yes, your straw-man version of the 2nd law is trivially false, but that's not what it says. (You make a valid criticism of that particular simplistic interpretation, granted.)
    – Rex Kerr
    Aug 18 '11 at 17:44
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    In addition to ignoring the fact that your living room is not a closed system and cannot be simply "defined" as such, another problem with your trivial objection is that you are doing the rearranging. The second law is really only concerned with how things tend absent some type of intervention. Stated a different way, the principle as applied to your analogy would hold that your furniture will never rearrange itself.
    – Cody Gray
    Aug 19 '11 at 5:23
  • The fact that furniture will never rearrange itself would be more philosophically interesting if this were a universe of only furniture. In other words: I am clearly setting up a strawman, because that strawman represents the usual arguments drawn by the lazy on the subject, who tend to collapse the distinction between the macroscopic and the microscopic, and between the differing philosophical and physical notions of information, entropy, etc. Aug 19 '11 at 6:55
  • Organizing your room does not decrease the entropy. Cooling down your room does. Only molecular organization is important, not the superficial macroscopic one we identify with our eyes. A rule of thumb: if you can see the order or disorder, it isn't entropy.
    – Ron Maimon
    Apr 13 '12 at 23:05
  • @RonMaimon That is not actually true. Any time you decrease the number of states a system can be in, you increase the information in the system, opposing the march of entropy. Where you are right is that the actual amount of entropy contained in macroscopic definitions of the room is very low compared to the amount of entropy found in a few dozen molecules, so the effect of organizing on entropy is low... but DECIDEDLY nonzero.
    – Cort Ammon
    Aug 12 '15 at 5:34

I would say the most profound implication is the irreversibility of time. What has happened cannot unhappen.

Scrambled eggs cannot be unscrambled and decoagulated. Well, theoretically a Maxwellian demon could do that, but that would be only the future of the egg molecules. History cannot be erased.

Another nice implication is that the second law of thermodynamics kills determinism once and for all. In a deterministic system there is no thermodynamics, only one microstate, the entropy of the system remains constant.

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