Eternalism (philosophy of time) 1

Eternalism (philosophy of time)Eternalism is a philosophical approach to the ontological nature of time, which takes the view that all points in timeare equally "real", as opposed to the presentist idea that only the present is real.[1] Modern advocates often takeinspiration from the way time is modeled as a dimension in the theory of relativity, giving time a similar ontology tothat of space (although the basic idea dates back at least to McTaggart's B-Theory of time, first published in TheUnreality of Time in 1908, only three years after the first paper on relativity). This would mean that time is justanother dimension, that future events are "already there", and that there is no objective flow of time. It is sometimesreferred to as the "block time" or "block universe" theory due to its description of space-time as an unchangingfour-dimensional "block",[2] as opposed to the view of the world as a three-dimensional space modulated by thepassage of time.

Problems with the flow of timeConventionally, time is divided into three distinct regions; the "past", the "present", and the "future". Using thatrepresentational model, the past is generally seen as being immutably fixed, and the future as undefined andnebulous. As time passes, the moment that was once the present becomes part of the past; and part of the future, inturn, becomes the new present. In this way time is said to pass, with a distinct present moment "moving" forwardinto the future and leaving the past behind. This view of time is given the name presentism by philosophers.This conventional model presents a number of difficult philosophical problems, and seems difficult to reconcile withcurrently accepted scientific theories such as the theory of relativity.

SimultaneitySpecial relativity suggests that the concept of simultaneity is not universal: according to the relativity ofsimultaneity, observers in different frames of reference can have different perceptions of whether a given pair ofevents happened at the same time or at different times, with there being no physical basis for preferring one frame'sjudgments over another's (though in a case where one event A happens in the past light cone of another event B, allframes will agree that A happened in the past of B). So, in special relativity there can be no physical basis forpicking out a unique set of events that are all happening simultaneously in "the present".Many philosophers have argued that relativity implies eternalism.[3] Although he disagrees in a qualified sense,philosopher of science Dean Rickles notes that "the consensus among philosophers seems to be that special andgeneral relativity are incompatible with presentism."[4] For example, Christian Wüthrich writes:

Presentists have responded in a variety of ways to the pressure exerted by the Rietdijk-Putnam argument... [A]presentist could deny Naturalism. Such denial could take different forms. One could, as does Jonathan Lowe,claim that SR is not a theory about time but about something else instead. Alternatively, once could retort byaccepting that SR speaks to the geometry of space-time but reject that this has any ontological import, as doesDean Zimmerman (2008). Second, a presentist might reject SR-Realism, simply asserting that SR is notapproximately true of the world. This could occur simply on a priori grounds... Also, considerations fromquantum mechanics can be invoked in an attempt to establish that SR is false or incomplete insofar as it lacksan absolute, privileged frame of reference. This response comes in different flavours: (a) (non-relativistic)collapse dynamics require a preferred frame in which the collapse occurs; (b) Bohmian interpretations areincompatible with SR; and (c) invoke Bell's theorem to argue that some tenets of SR must be given up...[A] presentist might simply bite the bullet and consequently relativize existence... since what is present isrelative to an inertial frame, what exists becomes fragmented in that it depends on the choice of frame...[Another] is to accept that SR offers a perfectly empirically adequate theory, but to insist that absolute simultaneity still exists. It is just that we cannot possibly detect the privileged frame of reference which

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determines the present. In other words, absolute simultaneity is not empirically accessible... [The] metaphysicsfully relies on postulated extra-structure that can't even in principle be observed... It violates Ockham's razorso crassly that the move cannot be justified by putting some post-verificationist philosophy of science on one'sflag.[]

—Christian Wüthrich, "No Presentism in Quantum Gravity" in Space, Time, and Spacetime: Physical andPhilosophical Implications of Minkowski's Unification of Space and Time

However, there are some, such as Dean Zimmerman, who have argued that it is possible to accept the physicalpredictions of relativity while adopting an alternative interpretation of the theory (For instance, see Lorentz ethertheory) in which there is a single privileged frame whose judgments about length, time and simultaneity are the"true" ones, even though there would be absolutely no empirical way to distinguish this frame from other frames, andno real experience could identify it.[5]

[When] appealing to findings from empirically well-grounded disciplines, philosophers face a strongtemptation to overstate their case — especially if their philosophical opponents can be relied on to berelatively innocent of new developments in the relevant science. I fear that some B-theorists have succumbedto the temptation, judging by the relish with which they often pronounce a verdict based on Relativity. Theycan practically hear the crunch of the lowly metaphysician’s armor giving way, as they bring the full force ofincontrovertible physical fact down upon our A-theoretically-addled heads. But what actually hits us, and howhard is the blow? SR is false; GR’s future is highly uncertain; and the presentist’s conflict with either versionof Relativity is shallow, since the presentist’s manifold can satisfy the same geometrical description as aB-theorist’s manifold, and afford explanations of all the same phenomena in precisely the same style. In thesecircumstances, how could appeal to SR or GR justify the frequent announcements that the A-theory–B-theorydispute has been “settled by physics, not philosophy”?[]

—Dean Zimmerman, "Presentism and the Space-Time Manifold" in The Oxford Handbook of Time

Rate of flowThe concept of "time passing" can be considered to be internally inconsistent, by asking "how much time goes by inan hour?" The question, "how fast does time pass" seems to have no satisfactory answer, in which answers such as "asecond per second" would be, as some would argue, circular and thus false. In addition, even if we do accept theabove answer, then the statement "a second per second" can be expressed as a fraction which is always equal to 'one'.But this 'one' has no meaning beyond being a number and is thus also the wrong kind of answer. Therefore, theargument goes, the rate of the passage of time is nonsensical.There is a major problem though in that the question of time is no different from space. One can similarly ask, "howmuch space is contained in a meter?" — and face a similar objection.'Time passing' may be seen as a methaphor for the continuous human experience of some expected future eventsbecoming directly experienced qualia, while experienced qualia becoming just objects of memory.

McTaggart's argumentIn The Unreality of Time, J. M. E. McTaggart divided time into an A-series and a B-series, with the A-series describing events in absolute tensed terms (past, present, and future) and the B-series describing events in terms of untensed temporal relations (before and after). He also added the notion of a "C-series", a series that has an order but with no notion of time, like a series of letters. He went on to argue that the A-series was needed for anything deserving the name "time",[6] since he argued that only the A-series can allow for genuine change,[7] and he considered change to be an essential part of any reasonable definition of time.[8] But, he argued, the A-series was logically incoherent,[9] so he concluded that time was unreal,[10] and since he also believed the B-series depended on the A-series,[11] he also concluded that only the C-series could remain as a meaningful ordering.[12] However, various philosophers (sometimes identified as "B theorists") have held that the remaining B-series qualifies as a valid

Eternalism (philosophy of time) 3

framework for a theory of time, sometimes called the B-Theory of time.[13]

The Eternalist alternativeEternalism addresses these various difficulties by considering all points in time to be equally valid frames ofreference—or equally "real", if one prefers. It does not do away with the concept of past and future, but insteadconsiders them directions rather than states of being; whether some point in time is in the future or past is entirelydependent on which frame of reference you are using as a basis for observing it.Since an observer at any given point in time can only remember events that are in the past relative to him, and notevents that are in the future relative to him, the subjective illusion of the passage of time is maintained. Theasymmetry of remembering past events but not future ones, as well as other irreversible events that progress in onlyone temporal direction (such as the increase in entropy) gives rise to the arrow of time. In the view suggested byEternalism, there is no passage of time; the ticking of a clock measures durations between events much as the markson a measuring tape measures distances between places.[citation needed]

Eternalism has implications for the concept of free will, in that it proposes that future events are as immutably fixedand impossible to change as past events (see determinism). [citation needed]

Eternalism makes two assumptions, which are separable. One is that time is a full-fledged real dimension. The otheris immutability. The latter is not a necessary consequence of the first. A universe in which changes are possible maybe indistinguishable from the fully deterministic many-worlds interpretation of quantum mechanics in which thereare multiple "growing block universes."[citation needed]

Philosophical objectionsPhilosophers such as John Lucas argue that "The Block universe gives a deeply inadequate view of time. It fails toaccount for the passage of time, the pre-eminence of the present, the directedness of time and the difference betweenthe future and the past"[14]

The comment summarizes the main objections. In more detail, they are:

Subjective sense of flowWhilst the idea that there is some objective sense in which time is flowing can be denied, the fact that consciousbeings feel as though it is in some sense flowing cannot. However, if the flow of time didn't have an objectiveexistence, then it is argued conscious beings would simultaneously experience all moments in their lives. A responseis that since the brain presumably perceives time through information processing of external stimuli, not byextrasensory perception, and obeys the laws of causality, it is hard to see how the flow of time, whether it exists ornot, could make any subjective difference: all conscious beings are built to perceive time as a chain of events,whether or not it occurs as such.

Apparent differences between past, present and futureMany of our common-sense attitudes treat the past, present and future differently.1.1. We apparently fear death because we believe that we will no longer exist after we die. But if Eternalism is

correct, death is just one of our temporal borders, and should be no more worrisome than birth.2.2. You are about to go to the dentist, or you have already been. Commonsense says you should prefer to have been.

But if Eternalism is correct, it shouldn't matter which situation you're in.3. When some unpleasant experience is behind us, we feel glad that it is over. But if the Eternalism is correct, there

is no such property as being over or no longer happening now—it continues to exist timelessly.

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Status of conscious observersEternalists often appeal to the idea that the flow of time is a subjective illusion. However, Eternalism takes itsinspiration from physics [citation needed] and needs to give a physical account of observers. One could, for instance,portray conscious observers as moving through the block universe, in some physically inexplicable way, in order toaccount for the subjective sense of a flow of time. But there is no need to do so to explain the subjective flow oftime.[citation needed] Their opponents claim that the time-flow itself, as an objective phenomenon, is physicallyinexplicable, and that physics is simply misrepresenting time in treating it as a dimension.[citation needed]

Determinism and indeterminismPreviously, it was noted that people tend to have very different attitudes towards the past and the future. This mightbe explained by an underlying attitude that the future is not fixed, but can be changed, and is therefore worthworrying about. If that is correct, the flow of time is perhaps less important to our intuitions than an open,undetermined, future. In other words, a flow-of-time theory with a strictly determined future (which nonethelessdoes not exist at the present) would not satisfy common-sense intuitions about time. If indeterminism can beremoved from flow-of-time theories, can it be added to Eternalist theories? Regarding John G. Cramer’s transactionalinterpretation, Kastner (2010) "proposed that in order to preserve the elegance and economy of the interpretation, itmay be necessary to consider offer and confirmation waves as propagating in a “higher space” of possibilities.[]

In his discussion with Albert Einstein, Karl Popper argued against determinism:The main topic of our conversation was indeterminism. I tried to persuade him to give up his determinism,which amounted to the view that the world was a four-dimensional Parmenidean block universe in whichchange was a human illusion, or very nearly so. (He agreed that this had been his view, and while discussing itI called him "Parmenides".) I argued that if men, or other organisms, could experience change and genuinesuccession in time, then this was real. It could not be explained away by a theory of the successive rising intoour consciousness of time slices which in some sense coexist; for this kind of "rising into consciousness"would have precisely the same character as that succession of changes which the theory tries to explain away. Ialso brought in the somewhat obvious biological arguments: that the evolution of life, and the way organismsbehave, especially higher animals, cannot really be understood on the basis of any theory which interprets timeas if it were something like another (anisotropic) space coordinate. After all, we do not experience spacecoordinates. And this is because they are simply nonexistent: we must beware of hypostatizing them; they areconstructions which are almost wholly arbitrary. Why should we then experience the time coordinate—to besure, the one appropriate to our inertial system—not only as real but also as absolute, that is, as unalterable andindependent of anything we can do (except changing our state of motion)?The reality of time and change seemed to me the crux of realism. (I still so regard it, and it has been soregarded by some idealistic opponents of realism, such as Schrödinger and Gödel.)When I visited Einstein, Schilpp's Einstein volume in The Library of Living Philosophers had just beenpublished; this volume contained a now famous contribution of Gödel's which employed, against the reality oftime and change, arguments from Einstein's two relativity theories. Einstein had come out in that volumestrongly in favour of realism. And he clearly disagreed with Gödel's idealism: he suggested in his reply thatGödel's solutions of the cosmological equations might have "to be excluded on physical grounds".Now I tried to present to Einstein-Parmenides as strongly as I could my conviction that a clear stand must be made against any idealistic view of time. And I also tried to show that, though the idealistic view was compatible with both determinism and indeterminism, a clear stand should be made in favour of an "open" universe—one in which the future was in no sense contained in the past or the present, even though they do impose severe restrictions on it. I argued that we should not be swayed by our theories to give up realism (for which the strongest arguments were based on common sense), though I think that he was ready to admit, as I was, that we might be forced one day to give it up if very powerful arguments (of Gödel's type, say) were to be

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brought against it. I therefore argued that with regard to time, and also to indeterminism (that is, theincompleteness of physics), the situation was precisely similar to the situation with regard to realism.Appealing to his own way of expressing things in theological terms, I said: if God had wanted to puteverything into the world from the beginning, He would have created a universe without change, withoutorganisms and evolution, and without man and man's experience of change. But He seems to have thought thata live universe with events unexpected even by Himself would be more interesting than a dead one.[]

—Karl Popper, Unended Quest: An Intellectual Autobiography

Relation to physicsEternalism takes its inspiration from physics, especially the Rietdijk-Putnam argument, in which the relativity ofsimultaneity is used to show that each point in the universe can have a different set of events that are in its presentmoment. According to Presentism this is impossible because there is only one present moment that is instantaneousand encompasses the entire universe.Some philosophers also appeal to a specific theory which is "timeless" in a more radical sense than the rest ofphysics, the theory of quantum gravity. This theory is used, for instance, in Julian Barbour's theory oftimelessness.[15] On the other hand, George Ellis argues that time is absent in cosmological theories because of thedetails they leave out.[16]

Relation to pre-McTaggart positionsAugustine of Hippo wrote that God is outside of time—that time exists only within the created universe. ThomasAquinas took the same view, and many theologians agree. On this view, God would perceive something like a blockuniverse, while time might appear differently to the finite beings contained within it.[17]

The philosopher Katherin A. Rogers argued that Anselm of Canterbury took an eternalist view of time,[18] althoughthe philosopher Brian Leftow argued against this interpretation,[19] suggesting that Anselm instead advocated for atype of presentism. Rogers responded to this paper, defending her original interpretation.[20] Rogers also discussesthis issue in her book "Anselm on Freedom", using the term "four-dimensionalism" rather than "eternalism" for theview that "the present moment is not ontologically privileged", and commenting that "Boethius and Augustine dosometimes sound rather four-dimensionalist, but Anselm is apparently the first consistently and explicitly to embracethe position."[21] Taneli Kukkonen argues in the Oxford Handbook of Medieval Philosophy that "what Augustine'sand Anselm's mix of eternalist and presentist, tenseless and tensed language tells is that medieval philosophers sawno need to choose sides" in the manner that modern philosophers do.[22]

In Buddhism, a special term Dharmadhatu is translated as 'total field of events and meanings' or 'field of all eventsand meanings.' Here the 'Block Universe' seems to be encompassing not only every possible event in the physicaluniverse but also having a psychological component.[citation needed]

Dirck Vorenkamp, a professor of religious studies, argued in his paper "B-Series Temporal Order in Dogen's Theoryof Time"[23] that the Zen Buddhist teacher Dōgen presented views on time that contained all the main elements ofMcTaggart's B-series view of time (which denies any objective present), although he noted that some of Dōgenreasoning also contained A-Series notions, which Vorenkamp argued may indicate some inconsistency in Dōgen'sthinking.

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In fictionEternalism is a major theme in Kurt Vonnegut’s novel, Slaughterhouse-Five. The Tralfamadorians, an alien speciesin the novel, have a four-dimensional sight and can therefore see all points in time simultaneously. They explain thatsince all moments exist simultaneously, everyone is always alive. The hero, Billy Pilgrim, lives his life out ofsequence, which, among other things, means that his point of death occurs at a random point in his life rather than atthe end of it.Eternalism also appears in the comic book series Watchmen by Alan Moore. In one chapter, Dr. Manhattan explainshow he perceives time. Since past, present, and future events all occur at the "same time" for him, he speaks aboutthem all in the present tense. For example, he says "Forty years ago, cogs rain on Brooklyn" referring to an event inhis youth when his father throws old watch parts out a window. His last line of the series is "Nothing ends, Adrian.Nothing ever ends."

ReferencesNotes[2][2] "Block" here refers to the idea of spacetime as something fixed and unchanging, like a solid block, and not to the actual geometric shape of

space or spacetime.[3] See footnote 1 of Thomas M. Crisp, "Presentism, Eternalism, and Relativity Physics" (http:/ / people. biola. edu/ thomasc/ thomasmcrisp/

Vita_files/ Presentism, Eternalism and Relativity Physics. pdf) in Einstein, Relativity and Absolute Simultaneity (2007), edited by WilliamLane Craig and Quentin Smith.

[4] Dean Rickles (2007). Symmetry, Structure, and Spacetime , p. 158 (http:/ / books. google. com/ books?id=gDwJYtfoCh8C& lpg=PP1&pg=PA158#v=onepage& q& f=false).

[5] see section 1.1.2 (http:/ / books. google. com/ books?id=juGJmF2OE30C& lpg=PP1& pg=PP22#v=onepage& q& f=false) of philosopherYuri Balashov's book Persistence and Spacetime (2010, Oxford University Press) for a brief discussion. Balashov himself considers this viewto be "misguided", but notes that "some authors" have advocated it, citing the following sources:

• Craig, William Lane (2001), Time and the Metaphysics of Relativity• Craig, William Lane and Smith, Quentin (2008), Einstein, Relativity and Absolute Simultaneity• forthcoming (at the time of Balashov's writing) paper by Dean Zimmerman, 'Presentism and the Space-Time Manifold' (http:/ /

fas-philosophy. rutgers. edu/ zimmerman/ Presentism and Rel. for. Web. 2. pdf) (see in particular the discussion starting on p. 90), toappear in Craig Callender (ed.), Oxford Handbook of Time

[6][6] "Time, as we have seen, stands and falls with the A series"[7][7] "Changes must happen to the events of such a nature that the occurrence of these changes does not hinder the events from being events, and

the same events, both before and after the change. Now what characteristics of an event are there which can change and yet leave the event thesame event? (I use the word characteristic as a general term to include both the qualities which the event possesses, and the relations of whichit is a term -- or rather the fact that the event is a term of these relations.) It seems to me that there is only one class of such characteristics --namely, the determination of the event in question by the terms of the A series."

[8][8] "It would, I suppose, be universally admitted that time involves change"[9] "My main thesis is that the existence of any A series involves a contradiction."[10][10] "We have come then to the conclusion that the application of the A series to reality involves a contradiction, and that consequently the A

series cannot be true of reality. And, since time involves the A series, it follows that time cannot be true of reality. "[11][11] The B series, on the other hand, is not ultimate. For, given a C series of permanent relations of terms, which is not in itself temporal, and

therefore is not a B series, and given the further fact that the terms of this C series also form an A series, and it results that the terms of the Cseries become a B series, those which are placed first, in the direction from past to future, being earlier than those whose places are further inthe direction of the future.

[12][12] "Our conclusion, then, is that neither time as a whole, nor the A series and B series, really exist. But this leaves it possible that the C seriesdoes really exist. The A series was rejected for its inconsistency. And its rejection involved the rejection of the B series. But we have found nosuch contradiction in the C series, and its invalidity does not follow from the invalidity of the A series."

[13] Loux, Michael (2006). Metaphysics: A Contemporary Introduction, Third Edition, p. 205 (http:/ / books. google. com/books?id=3i1YVPLzSa0C& lpg=PP1& pg=PA205#v=onepage& q& f=false)

[14] John LucasThe Future p8[15] "Platonia", Julian Barbour's time-skeptical website (http:/ / www. platonia. com)[17] John Polkinghorne (2011). Science and Religion in Quest of Truth, p. 64 (http:/ / books. google. com/ books?id=pdeUz0_WXP8C&

lpg=PP1& pg=PA64#v=onepage& q& f=false).[18] Katherin A. Rogers (2007). "Anselmian Eternalism" (http:/ / philpapers. org/ rec/ ROGAEA). Faith and Philosophy 24 (1):3-27.[19] Brian Leftow (2009). "Anselmian Presentism. Faith and Philosophy" (http:/ / philpapers. org/ rec/ LEFAP-2) 26 (3):297-319.

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[20] Katherin Rogers (2009). "Back to Eternalism" (http:/ / philpapers. org/ rec/ ROGBTE). Faith and Philosophy 26 (3):320-338.[22] From Kukkonen's chapter on "Eternity" in The Oxford Handbook of Medieval Philosophy edited by John Marenbon (2012), p. 529 (http:/ /

books. google. com/ books?id=2TbPp5I6nL8C& lpg=PP1& pg=PA529#v=onepage& q& f=false).[23] Vorenkamp, Dirck (1995). "B-Series Temporal Order in Dogen's Theory of Time" (http:/ / web. archive. org/ web/ 20101206055549/ http:/ /

ccbs. ntu. edu. tw/ FULLTEXT/ JR-PHIL/ dirck. htm). Philosophy East and West, Volume 45, Number 3, 1995 July, P.387-408.

Bibliography• Smart, Jack. "River of Time". In Anthony Kenny. Essays in Conceptual Analysis. pp. 214–215.•• van Inwagen, Peter (2008). Metaphysics. Stanford Encyclopedia of Philosophy.

External links• Biswas; Shaw; Modak (1999). "Time in Quantum Gravity". Int.J.Mod.Phys. D 10 (4): 595. arXiv: gr-qc/9906010

(http:/ / arxiv. org/ abs/ gr-qc/ 9906010). doi: 10.1142/S0218271801001384 (http:/ / dx. doi. org/ 10. 1142/S0218271801001384).

• Davies, Paul (September 2002). "That Mysterious Flow". Scientific American 287 (3): 40–45. doi:10.1038/scientificamerican0902-40 (http:/ / dx. doi. org/ 10. 1038/ scientificamerican0902-40).

• Dorato,Mauro - Kant, Godel and Relativity (http:/ / philsci-archive. pitt. edu/ 638/ )• Markosian, Ned (2002). "Time: 8. The 3D/4D Controversy" (http:/ / plato. stanford. edu/ entries/ time/ #3D4Con).

Stanford Encyclopedia of Philosophy. Retrieved 2006-12-20.• Nikolic, Hrvoje. "Block time: Why many physicists still don't accept it?" (http:/ / fqxi. org/ data/

essay-contest-files/ Nikolic_FQXi_time. pdf).• Petkov, Vesselin (2005). "Is There an Alternative to the Block Universe View?" (http:/ / Philsci-Archive. Pitt.

EDU/ archive/ 00002408/ ) (PDF). PhilSci Archive. Retrieved 2006-12-20.• Duda, J (2009). "Four-dimensional understanding of quantum mechanics". arXiv: 0910.2724/ (http:/ / arxiv. org/

abs/ 0910. 2724/ ).• Wüthrich, Christian (2011). "The fate of presentism in modern physics" (http:/ / philsci-archive. pitt. edu/ 8765/ ).

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