From the Stanford Encyclopedia
The A Theorist is normally happy to concede McTaggart's claim that there can be no time without an A series, but the typical A Theorist will want to reject the part of McTaggart's argument that says that the A series is inherently contradictory. For the typical A Theorist will deny McTaggart's claim that each time in the A series must possess all of the different A properties. That is, she will deny that it is true of any time, t, that t is past, present, and future. Instead, she will insist, the closest thing to this that can be true of a time, t, is (for example) that t was future, is present, and will be past, where the verbal tenses of the verb ‘to be’ in this claim are not to be analyzed away (just as the apparent references to the putative A properties pastness, presentness, and futurity are not to be analyzed away in favor of reference to B relations).
Thus the standard A Theorist's response to McTaggart's argument involves the notion that we must “take tense seriously,” in the sense that there is a fundamental distinction between (for example) saying that x is F and saying that x was F. The thesis can be put this way.
Taking Tense Seriously: The verbal tenses of ordinary language (expressions like ‘it is the case that’, ‘it was the case that’, and ‘it will be the case that’) must be taken as primitive and unanalyzable.[3]
In virtue of her commitment to Taking Tense Seriously, the A Theorist will say that no time ever possesses all of the different A properties. Thus, according to the A Theorist, there is no contradiction in the A series — i.e., no contradiction in saying of a time, t, that t was future, is present, and will be past — and, hence, no contradiction to be passed along to the different times at which t was future, is present, and will be past.
In effect, then, the typical A Theorist makes exactly the move in response to McTaggart's argument that McTaggart anticipated, and explicitly rejected. Not surprisingly, then, many supporters of McTaggart's argument feel that the A Theorist's response fails.
Although some B Theorists deny that time really passes as a result of considering McTaggart's argument, many B Theorists have different reasons for saying that time doesn't really pass. Two other arguments against The A Theory (besides McTaggart's argument, that is) have been especially influential. The first of these is an argument from the special theory of relativity in physics. According to that theory (the argument goes), there is no such thing as absolute simultaneity. But if there is no such thing as absolute simultaneity, then there cannot be objective facts of the form “t is present” or “t is 12 seconds past”. Thus, according to this line of argument, there cannot be objective facts about A properties, and so the passage of time cannot be an objective feature of the world.
It looks as if the A Theorist must choose between two possible responses to the argument from relativity: (1) deny the theory of relativity, or (2) deny that the theory of relativity actually entails that there can be no such thing as absolute simultaneity. Option (1) has had its proponents (including Arthur Prior), but in general has not proven to be widely popular. This may be on account of the enormous respect philosophers typically have for leading theories in the empirical sciences. Option (2) seems like a promising approach for A Theorists, but A Theorists who opt for this line are faced with the task of giving some account of just what the theory of relativity does entail with respect to absolute simultaneity. (Perhaps it can be plausibly argued that while relativity entails that it is physically impossible to observe whether two events are absolutely simultaneous, the theory nevertheless has no bearing on whether there is such a phenomenon as absolute simultaneity.)
The second of the two other influential arguments against The A Theory concerns the rate of the alleged passage of time. According to this argument, if it is true to say that time really passes, then it makes sense to ask how fast time passes. But (the argument goes) if it makes sense to ask how fast time passes, then it is possible for there to be a coherent answer to that question. Yet, according to the argument, there is no rate that can be coherently assigned to the passage of time. (“One hour per hour,” for example, is said not to be a coherent answer to the question “How fast does time pass?”) Thus, the argument concludes, it cannot be true to say that time really passes.
Edited by Duchykins, 30 July 2014 - 05:16 AM.
