Presentism is the view that past and future entities don't exist and thus only things in the present do exist, and it is a contrasting view to eternalism which is the view that everything in the past, present and future exist. Although presentism seems like a plausible way of thinking, it faces a few problems that I will explore in this essay. I will determine which problem I deem to be the greatest and then deduce whether this convinces me to think that presentism is wrong.
According to those who believe in the four-dimensional view, time travelling is possible whereas, to believe in presentism means that one would usually view time travelling as incompatible. The four-dimensional view is one where all times and space exist thus a supporter would usually support eternalism also. A time traveller by definition is able to reach any time in the future or in the past "where the duration of the trip is unequal to the difference between the arrival and departure times" (Keller and Nelson, 2001:334). Since time travellers can reach any point in time, there is already a noticeable problem with presentism. A presentist would say that this is impossible since only the present exists, therefore you simply can't travel to a point in time which doesn't exist. On the contrary, an eternalist would say that since all past, present and future entities exist it is possible to time travel. This argument is often referred to as the "nowhere argument". This argument has faced much criticism because it rules out the ability of time travelling but also the actual aspect of moving forward in time if presentism is true. For example, when we move forward in time, to the immediate future, we just reached a point in time that did not previously exist when we started. Since we know that we can travel to times that don't exist because these so-called journeys are endlessly being made it causes a problem for the presentist. This is problematic since either presentism isn't a coherent theory or time travel must be accepted by the presentist. Assuming presentism is a plausible theory, then this argument implies that time travel is compatible with presentism. Thus, despite the fact that time travelling seemed to be problematic for presentism it can be combatted. However, Daniels (2012:472) and other philosophers consider this version "naïve" with Daniels focusing on Miller's alternative version of this. A similar version of the nowhere argument can be formulated for someone who is travelling from the future to the present. Due to the open future doctrine, it is not determined whether the time traveller will even depart, so it is impossible to travel from a time that doesn't exist to one that exists. However, the time traveller must leave from the future to the past, otherwise they wouldn't be a time traveller. Therefore, time travelling appears to not be compatible with presentism, which is a problem for the presentist. However, I do not believe this is presentism's biggest problem since a presentist can respond by endorsing a weak open future doctrine (Daniels, 2012:475-476).
This means that the presentist can dispute Miller's open future doctrine, which states that any future may or may not happen (2005:228). The presentist may say that all possible ways that the future pans out include the departure of the time traveller to the current present time. Therefore, only things after the time traveller's departure are deemed indeterminate. So, time travelling can be seen as possible if you endorse a weak open future doctrine since it is true that when the time traveller arrives, they will depart in all possible futures due to backwards causation (Daniels, 2012:476). This counter-argument shows that presentism is compatible with time travelling, however, the presentist has to accept a weak form of determinism in the fact that everything up to her departure is determined. This is quite controversial, however, if we accept this then we can say that time travelling cannot be the biggest problem faced by presentist since it can be successfully countered, albeit with some controversy. I will explore another problem of presentism and explain why I think this is the biggest problem.
Truth-making is another problem that the presentist is faced with and I will analyse why this is the case, and why I think it is the biggest problem. As we have already seen, the presentist believes that only present entities exist. The presentist will have to agree that entities have been in existence or will come into existence, but this is a problem for presentism. According to maximalism, something is only true when there is a truth-maker. The problem for the presentist is that since past and future entities don't exist then there can't be any truth-makers about the past or future and therefore, propositions about the past or future cannot be deemed true. This is problematic since it insinuates that the theory of presentism is wrong. In order to combat this, the presentist must object the maximalism view. If the presentist can deny maximalism then truth-making cannot be deemed a problem for presentism since, if this is the case, every truth will not need to have a truth-maker. In order to do this, the presentist can take a standard negative proposition such as "There are no artic penguins" (Tallant, 2009:409). The Penguins don't make the proposition true that there are no penguins in the artic (Tallant, 2009:409). According to maximalism, existing entities make propositions true, but the presentist can challenge that this view cannot be applied to negative existentials as they regard things that don't exist. Therefore, if we reject maximalism on the account that negative existentials don't have truth-makers then it is possible to make the claim that truths about the past can also lack them. With that said, it is problematic for the presentist to prove the analogy between the truth-makers of negative entities and past entities. Therefore, I will summarise the objection to this claim and prove the truth-making is the biggest problem for presentism since it is very difficult for the presentist to prove the analogy and thus disprove maximalism. The presentist needs to establish a link between all of the truths about the past are similar to negative claims, in order to say that views about the past don't need truthmakers. Asay and Baron (2014:11) state that this is not possible since there are many claims about the past that are "intuitively true and are disanalogous to fully general/partially general negative claims in terms of their scope". They use the proposition of "Socrates was not a sophist" and say this is analogous to specific present negative claims. An example of this would be "I am not flying". For this negative existential, there is a truth-maker in the form of evidence of me sitting or standing. Therefore, it seems that the act of me standing guarantees the truth of "I am not flying". Consequently, it is not possible to establish a claim between negative claims and those of claims from the past. A more compelling argument in Asay and Baron's paper (2014:12-13) is when they compare fictional propositions with past propositions. Let's say in our example "zombies existed" and "dodos existed". The presentist has a problem with maintaining that the latter is true whilst the former isn't. To say that there is a truth-maker that makes the proposition that "dodos existed" true goes against the initial aim of the presentist; they want to disprove maximalism. However, without admitting that one of these propositions has a truth-maker makes it impossible for the presentist to differentiate between the past and fictional past. To do this, the presentist has to embrace the fact that truths about the pasts do have truth-makers, but this defeats their whole objective. In summary, the presentist cannot beat the problem of truth-making as it is not possible for the presentist to prove the analogy between a negative proposition and a past proposition and a fictional proposition with a past one. Therefore, since the presentist cannot deny maximalism, truth-making is presentism's biggest problem.
Overall, despite initially holding a presentism view I feel that the greatest problem of presentism, that of truth-making, convinces me that the theory is wrong. This is because it is not possible to argue against the truth-making objection, due to the fact they can't differentiate between the past and the fictional without accepting the maximalism, that they wish to combat in order to defeat the objection. Moreover, it is possible to question the counter-argument to the problem of time travelling since the defence is contentious. In conclusion, I am forced to take the view that presentism cannot be a coherent theory in the face of these problems. Therefore, the greatest problem and in fact both problems mentioned in this essay do cause me to view the theory of presentism as wrong, thus I ought to consider the theory of eternalism which at first viewing does not face the problems presentism faces.