Here's a paper I wrote back in college in a philosophy of science course... please let me tell you that when I set out to write this paper I wanted to title it the Unreality of Time but my research in writing this paper has changed my position on this topic.
Written on: April 28, 2004
The concept of time has been a subject of dispute ever since ancient times. This is so mainly because we live in time so we do not see the full picture of time. Einstein suggested that we live in a four-dimensional world consisting of Newton’s three dimensions: length, breadth, and width, plus the fourth dimensional concept called time. In Newton’s universe there exists only the three former dimensions and that time is something that “flows equably without relation to anything external” (Principia Scholwer to DEF VIII). He also believed that these three dimensions are constants where as Einstein suggested that nothing is constant except for two things: one being the velocity of light, and two, causation (McFarland 18). The reality of time is apparent to most people and it has been supported by various physicists and theologians. John McTaggart, on the other hand, shares a different view on this with his argument that aims to prove the unreality of time. I will argue that time is real, opposing McTaggart’s proof by denying the reality of the A series and that there is no genuine change in the universe.
Albert Einstein suggests that everything that we perceive in the world that we know is relative to everything else. His famous Theory of Relativity describes, on the one hand, the relation between the observations of observers who move relative to each other in their various reference frames. For instance, if person A were to travel away from earth and person B stay on earth, we could say that B is moving away from A or we could also state that A is moving away from B. On the other hand, his theory is also an interpretation of how gravity plays a role in the whole scheme of relativity. As mentioned earlier, the speed of light is constant and thus it is independent of the reference system of the observer. It is a limit that can't be exceeded by any kind of matter without transforming in to pure energy, other wise known as the light barrier. This means that every time a measurement is taken of light’s speed it would always be approximately 3.0 x 108 meters per second, whether you stand still or move at 50% of light speed. Light speed is a universal constant which means that “time passes slower when you move than when you stand still” according to Einstein (McFarland 16).
Einstein’s Twin Paradox is a good example in illustrating the relative characteristic of time. The paradox is an interesting experiment involving two twins, who are nearly exactly the same age, one of whom sets out on a journey into space and back. Because of the time dilation effect of relativity, the twin who left experiences a slowing down of time and will actually be much younger than the twin that stayed behind. The reason that this is considered a paradox is that Special Relativity implies that either one can be considered at rest, with the other moving (Davies [How to…] 13). There are two ways to analyze this: 1) The twin staying on earth is at rest and the twin going on the journey is accelerating 2) the twin that goes on the journey is at rest and that the twin on earth is accelerating away and back. According to the latter view, the result of the paradox would be contradictory to itself. The question arises: Why does time slow for the twin traveling away from earth and not for the twin staying on earth if we use the second frames of rest. Therefore, time has the characteristic of being relative to the space-time velocity system of the viewer (Gale 93).
McTaggart argues that there is in fact no such thing as time, and that the appearance of a temporal order to the world is a mere appearance. He supports this in a work he published in 1908 called “The Unreality of Time.” He begins by characterizing that there are only two ways in which we can distinguish positions in time. One way is by referring to events as movement through time by using words such as past, present, or future: this he named the A-Series. The B-Series on the other hand, consists of orderly, related events, such that if Bob is before Jane, and Tom is after Bob, then Jane is always after Bob and before Tom. This series if put into two dimensions would more or less look like a number line of related events in the same space-time velocity system.
Furthermore, McTaggart’s proof of the unreality of time includes the use of deductive reasoning by introducing the concept of change in the universe. McTaggart argues that the B series alone does not constitute a proper time series, and the A series is essential to time. His reason for this is that change is essential to time, and the B series without the A series does not involve genuine change, since B series positions are forever “fixed,” whereas A series positions are constantly changing. McTaggart also argues that the A series is “inherently contradictory”. For this, he says that each of the different “A properties are incompatible” with one another. No time can be both future and past and future. Paul Horwich, a B-series philosopher who holds that McTaggart’s Paradox is cogent, rejects the claim that the Paradox has shown time itself to be unreal. Instead of proving his theory completely false, he holds that McTaggart’s Paradox demonstrates that the idea of tensed time, or the A series, is incoherent; and he sees that the Paradox as supporting evidence for the B series (Farmer 20). For instance, in his Asymmetries in Time Horwich points out that “it is impossible that the history of the universe contain the three facts: E is past, E is now, E is future” (Farmer 134). Nevertheless, McTaggart insists, for each moment in the A series it must possess all of the different A series properties, since a time that is future will eventually be present and past, and etc (Horwich 24). Thus this is false due to Horwich’s claim from above, and therefore, time must be real.
McTaggart interprets other philosophers’ views on time as being unreal in his brief introduction to the Unreality of Time, “In philosophy… time is treated as unreal by Kant… ” (McTaggart 110) Kant’s account of McTaggart’s proof exhibits a different perspective on his argument according to some people. Kant's general opinion of how we see the world is that we don't actually experience the objects we perceive. Just like we wouldn't consider a photograph of a tiger to be an actual tiger; no one would be scared of the animal just by viewing its picture. According to Kant we should not trust all the information we receive by our five senses. Thus, in truth, all we experience is the representation of the animal not the animal itself. Thus, there is no on-goingness in time; everything is all there at once. Hence, McTaggart’s A series is false.
In proving that the A series is untrue, we can now move on by saying that there is no genuine change, that everything is all there at once, supported by absolutists. In the absolutist view of the world, there is no present, future, or past, there is everything at once. McTaggart's example of the Greenwich Prime Meridian further demonstrates his misleading view for the necessity of his A series. Assuming that time is one dimensional; we can imagine the Greenwich meridian being a time line. Call point X, within the United Kingdom, "Monday". Point X’, not in the United Kingdom, shall be called "not Monday". If time is one dimensional, and we exist at a single point in time, then we can imagine ourselves as observers standing either at X (Monday) or X’ (not Monday) or somewhere else, but never in more than one place on the Greenwich meridian. If we stand at Monday and look around, we see the United Kingdom. Traveling to Tuesday, we see something which is not the United Kingdom. When asked if there was a change, we must say "Yes, there was a change." Now imagine that we have broken free of our one-dimensional time line and we are now orbiting above the earth looking at the Greenwich meridian. We see a line drawn on the surface of the earth. Is there any change? Of course not, we are looking at a line that always spans the globe. The point of this is to demonstrate that as long as we consider ourselves the be within time, and only able to experience the present, then we will see change as we move along a time line. If we are looking down upon time from a different dimension, we are able to see more than one point of time at once and will not see the change. McTaggart clearly states that we only experience the present, but violates this statement with his example. In this argument McTaggart was looking for change in the “wrong place”, and McTaggart's retort only strengthened this contention (Farmer 138). Thus, time must be absolute and that change is nonexistent, and if there is a sense of change, it only exists perceptually, relative to the viewer’s position and his or her frame of reference.
In addition, we may refer to time as eternal, but there is more than one way of interpreting eternity. The Christians believe that God is eternal and others say that God created time. When referring to the word “eternal” there are two completely different ways of defining it. One definition of eternal is for something to be “everlasting or existing without beginning or end for an infinite duration” (Davies’s [God…] 133). An absolutist would side with this first definition in that it accounts time as being all there at once instead of ever changing. The other definition, contrary to the first, simply defines eternal as being “timelessness” (McTaggart 113).
Furthermore, taking the view on the other side of McTaggart’s argument we would assume that there is genuine change and that time is not eternal. Some theologians suggest that time is growing or expanding and thus ever changing. In this view, we can deny the validity of McTaggart’s B series because if time is forever growing and expanding, then there is no future when we are at now. If we are at the present, there is only now and the past. Thus, this proves the falsity of his B series and that since there is genuine change, we can say that time is also real (Farmer 110).
If I had to take a side, I would most likely support Horwich and numerous other scientists on accounting that in fact time does exist. Contrary to McTaggart’s proof of the unreality of time, I disagree with there being change in the space-time velocity system which we live in. I believe that there is absoluteness in the universe and that change is unreal, it is more or less an illusion played by our perception of the world. Furthermore, I think that the A series is not a correct interpretation of the world. In his discussion between the skeptic and the physicist, in his God and the New Physics, the skeptic poses a very common question: “why [do] I feel the flow of time?” The physicist explains that it is all illusory what the brain tells us we feel, and that it most likely has to do with short-term memory processes. He refutes this further by giving the example that despite the feeling of “the world is spinning” when you experience dizziness, you do not actually believe that the entire world is rotating. He says that “the whirling of time is like the whirling of space—a sort of temporal dizziness—which is given a false impression of reality by our confused language, with its tense structure and meaningless phrases about the past, present and future” (Davies [God…] 132).
By reiterating the two slips of the McTaggart Paradox, we can prove that time does exist and that his A series can exist without the B series and vice versa. If we deny the A series, we would assume that there is no genuine change in the universe, that time does not actually flow from future, to present, and then to past. Similarly, if we suppose that his B series is false, then we would say that there is genuine change except that there is only a past and a present. In this view, there is no future because time is ever changing itself by expanding and growing, creating new “now’s”. Thus, if you are in the present speaking of the future, you would be speaking falsely. Based on these two rebuttals of McTaggart’s proof, we can conclude that time is indeed real and that by denying one of the two series we can prove its reality.
Bibliography and Reference:
Brown, J.R.,ed. Davies, P.C.W., ed. The Ghost in the Atom. Cambridge, Great Britain: University Press, 1995.
Davies, Paul. How to Build a Time Machine. New York: Penguin Putnam Inc., 2001.
Davies, Paul. God and the New Physics. New York: Simon & Schuster, Inc., 1983.
Farmer, David J. Being in Time. Lanham, ME: University Press of America, Inc., 1990.
Gale, Richard M. The Language of Time. New York: Humanities Press Inc., 1968.
Horwich, Paul. Asymmetries in Time. Cambridge: The MIT Press, 1987.
McFarland, Ernie. Einstein’s Special Relativity. Toronto: Trifolium Books Inc., 1998.
McTaggart, J. McT. Ellis. Philosophical Studies. Freeport: Books for Libraries Press, Inc., 1966.
Principia Scholwer to DEF VIII.
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