The Philosophy of Time: A & B-Theory & the Kalam Cosmological Argument.

Screen Shot 2017-08-05 at 10.39.40 AM.png

Image Credit: Masco Digital Photography.

Philosophers identify two broad competing views on the nature of time: A-theory and B-theory (1). Whichever theory one adopts, it will certainly shape how one views reality. In theology and the philosophy of religion, how one sees the nature of time will also influence how he or she sees God.

These concepts were initially proposed by the idealist philosopher John McTaggart in his 1908 paper, The Unreality of Time. McTaggart saw A-theory as contradictory though he still believed that A-properties (such as being past) are essential to our current concept of time. McTaggart deduced that our current concept of time is incoherent, a conclusion referred to as “McTaggart’s Paradox” (2). His designation of A and B-theory isn’t necessarily the most creative, but it works well enough, and his ideas have lead to considerable development within philosophy of time.

The real difference between the two theories concerns whether or not time is tensed (A-theory) or tenseless (B-theory). A-theory is tensed in the sense that if one were to say that “I am in the middle of training,” the statement depends on the temporal perspective, namely, the present. On A-theory, there is a real difference between past, present, and future; these are real objective features of reality. Right now the present is all that exists, a view known as presentism, whereas the past no longer exists, and the future is still yet to exist and is based on potentiality (it is not fixed and determinate like the past); philosopher Ted Sider explains that “Presentism is the doctrine that only the present is real” (3). On A-theory, temporal becoming is a core feature which means that things and events come into being and go out of being. For example, a past historical event such as Caesar crossing the Rubicon with his army has already occurred and receded into the past, hence no longer exists. Philosopher Jonathan Tallant, though not an advocate for presentism, explains the general idea postulated by the presentist is like “When I wave my hand, I destroy what used to exist and make some new thing come into existence” (4). On this view the past and future only exist subjectively whereas only the present exists objectively outside of our minds. Though B-theory has a large number of advocates among physicists and philosophers, A-theory is what would seem to prima facie justified and intuitively obvious.

Alternatively, a B-theory (also known as a tenseless or static theory) of time says says there isn’t a difference between past, present, and future, and that they are all equally real, a view referred to as eternalism. So, for example, something that has occurred in one’s past is still real, and hasn’t simply just gone out of existence. On this view, both Plato and tomorrow’s events exist right now even though they are not in the same space-time vicinity, and even though one cannot interact or see them (5). The future too, is just as real as the present. Thus, according to the B-theorist, that we perceive of a continuum such as past, present, and future is ultimately an illusion of human consciousness. Temporal becoming does not exist on such a view as things and events do not come in and out of existence, there is no flow of time or passing of time. For example, one’s birth is not receding into the past and becoming ever more past. Philosopher William Craig is critical of B-theory saying that A-Theory “accords with our experience of time. We all experience the present-ness of time and I see absolutely no reason to think that this is a gigantic delusion that has been foisted upon us. I see no reason to think this is illusory” (6). However, many reject A-theory and presentism in favor of eternalism because they argue the former is in conflict with Einstein’s Special and General Theory of Relativity whereas eternalism agrees with it (7). According to Dean Rickles, a philosopher of science, “the consensus among philosophers seems to be that special and general relativity are incompatible with presentism” (8) which, says Tallant, is the “biggie” and a “sizable weakness.” What is argued, is that the theory of special and general relativity shows convincingly that there is no such thing as absolute simultaneity, an important requirement for A-theory. The relativity of simultaneity says that viewers in different frames of reference can potentially have different perceptions of events and whether or not those events occurred at the same time or at different times. It is argued that it is impossible to determine in an absolute sense that two distinct events occur at the same time if those events are separated in space. Nonetheless, many philosophers who argue that A-theory is not only in opposition to special and general relativity but also, as Taggart saw, contradictory, they still do not deny the reality of time itself (9).

Now, there is significance where the Kalam Cosmological Argument argument is concerned. If one, for example, could show that B-theory were true, then the Kalam loses is potency. Given that B-theory says that time is purely subjective on the part of an individual, there is no “now,” or temporal becoming. Craig, the leading proponent and defender of the Kalam Cosmological Argument, says that the argument is established on an A-Theory of time, “On a B-Theory of time,” Craig explains, “the universe does not in fact come into being or become actual at the Big Bang; it just exists tenselessly as a four-dimensional space-time block that is finitely extended in the earlier than direction. If time is tenseless, then the universe never really comes into being, and, therefore, the quest for a cause of its coming into being is misconceived” (10). This is then of obvious concern related to the 2nd premise of the argument that says that “that everything that begins to exist has a cause.” Philosopher Paul Copan observes that on a B-theory of time critics of the Kalam Cosmological Argument argue that the universe doesn’t actually come into being or become actual at the Big Bang, rather, “it just exists tenselessly as a four-dimensional space-time block that is finitely extended in the earlier than direction.” Others, however, have argued that the Kalam cosmological argument does not have to involve a commitment to the A-theory (11).


1. YouTube. 2011. The Philosophy of Time. AvailableAvailable.

2. Dowden, B. Internet Encyclopedia of Philosophy: Time. Available.

3. Craig, W. 2007. God and Time. Available.

4. YouTube. 2011. Ibid.

5. Markosian, N. 2002. Time. Available.

6. Craig, W. 2007. Ibid.

7. Markosian, N. 2002. Ibid.

8. Rickles, D. 2007. Symmetry, Structure, and Spacetime. p. 158.

9. Markosian, N. 2002. Ibid.

10. Craig, W. 2012. The Blackwell Companion to Natural Theology. p 183-184.

11. Waters, B. 2015. “Toward a new kalām cosmological argument,” in Cogent Arts and Humanities. 2 (1): p. 1–8.


3 responses to “The Philosophy of Time: A & B-Theory & the Kalam Cosmological Argument.

Let me know your thoughts!

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s