Objection 2: The Past and Future Are Real
We may reject Augustine’s original 1: the past and future do not exist. We hold that the past and future are real; they do exist. Something that exists—the past or future—also has duration. If the past and future are mind-independent, then duration—and thus time—can be mind-independent.
As discussed in Chapter 2, this is to admit the position of eternalism. If we deny 1, then we get a different conclusion to Augustine. There can be time because there is something real with duration—both the past and future.
Presentists cannot accept this solution, however. Furthermore, if we wish to remain neutral about the presentist/eternalist debate, we cannot accept this solution. To be neutral about this debate is to avoid committing to either eternalism or presentism. Holding that the past and future are real is being an eternalist; it is not being neutral.
Objection 2: The Present Can Have Duration
We could deny either 3 or 4—and through denying either one, deny 5. The result of this denial is that the present can have duration, and so something real can have duration.
However, to deny 3 or 4, we must also bring in thinking about metaphysics (as discussed in the first metaphysics of time chapter).
If we deny 4, then the present does include some of the past and future. It includes a bit of the past just before a particular moment in the present and a bit of the future just after a particular moment in the present. These bits of the past and future combine together to give the present at least some duration.
Let us say we accept presentism, that the past and future are unreal (that, is the first premise, 1). If, as presentists, we also deny 3, then multiple moments of the present are not past or future. This allows these moments to be real, given presentism—-just because they are not past or future, but present moments.
However, even as presentists, this kind of response runs into problems. These are problems it shares with tense theory eternalism, a general problem with having multiple present moments.
So, let us move on to eternalism. Eternalists generally can hold that there is a real present, past, and future. Thus, eternalists can deny 1. As such, they can have real durations. However, one of the reasons for holding that there is duration is that duration is in some way apparent to us. And part of St Augustine’s problem is that we are not aware of the past and future. So, we may have a real duration because of a real past and future. But can that real duration also be apparent to us?
Not, it seems, if one is an eternalist and also a tense theorist. If an eternalist is a tense theoristthen they cannot hold that the present is partly past or future— at least, a present they care about. As discussed in Chapter 2, tense theorists hold that time is fundamentally a single А-series of events or moments organized into the past, present, and future. This А-series includes a unique present that separates the past from the future. In such a series, the present is precisely not the future or past. Indeed, it is a single moment separate to both. As such, it has no part that is future or past. So, tense theorists must accept 4.
As also discussed in Chapter 2, tense theory can have other А-series, derivative А-series. Thus, one might hold that the present belongs to one А-series, for example, the fundamental А-series, while the past and future that are part of it belong to another (derivative) A-series.
However, that does not help the tense theory response. These other series are defined by either the fundamental А-series or a В-series, which is itself derived from the fundamental А-series. In either case, these other А-series positions are not really the positions of something, and any duration dependent on such A- series is not really its duration (for more on this, see Power 2016).