Time travel has been in the imaginations of some of our most creative thinkers for many years. Over time, our fascination with previewing the future and visiting the past has been tested by several paradoxes. One such paradox is that of the “no destination” argument. The argument is articulated by William Grey in his article “Troubles with Time Travel,” with his main argument being that a destination must exist for travel to be possible and according to a popular view that the past is fixed and the future is not yet existing, time travel is impossible. Phil Dowe, in his article “The Case for Time Travel,” comes to the rescue and presents flaws within Grey’s argument which help break the paradox of no destination. He presents the weaknesses in Grey’s presentation of the no destination paradox by showing that it doesn’t imply time travel is impossible in the Heraclitean view and that it lacks the ability to be applied to all theories of time and stay valid due to Grey‘s confusion between changing and causing the past. Dowe’s objections to Grey’s challenge to time travel allows for the hopes and wishes of time traveler supporters to remain alive.

               Grey presents the no destination argument through the Heraclitean view that only the present is real and that the past and future do not have eternal existence. This view of time is more popularly known as Presentism. From this view it is logical to understand his argument through the premises that “time travel is possible only if a destination exists, the past and future do not exist, and therefore time travel is impossible.” Although he follows the view that the past and future do not exist, he also presents an argument for the block theory of time (that the past exists yet fixed and unchangeable and the future is open and not yet existing) which follows that “if travel to the past were possible, the traveler could change the past, the past is fixed and unchangeable, and therefore, travel to the past is not possible.” His arguments presented in this light are logical, yet there are flaws that can be found within the premises which can leads to its unsoundness.

               Dowe responds to the no destinations paradox by first touching upon the fact that it doesn’t matter that the destination doesn’t exist when you depart, but that it exists when you arrive. He uses the analogy of waiting for tomorrow to demonstrate how although tomorrow does not yet exist, at some point we arrive at that tomorrow, which then would not rule out traveling to something that does not exist. I think a better argument can be constructed by focusing on tomorrow becoming today or in other words the future becoming the present which then exists. As the time traveler travels into the future, the future becomes his present and therefore his destination exists, but this destination only exists when he arrives (when it becomes his present) and not when he departs, according to the presentists perception of time. With these arguments, we can successfully show that there is nothing paradoxal about time travel into the future in the

Heraclitean or Presentist view.

               Dowe’s second point comes from Grey’s lack of applying the no destination paradox to other conceptions of  time, primarily the Parmenidian perception of time. The Parmenidian perception of time views the past, present and future as eternal truths which are fixed. Interestingly enough, in this case, it seems as though this view of time would support Grey’s argument, but Dowe objects to this by drawing upon the difference between changing and causing the past or future.

               The discussion on changing and causing the past is viciously explored by many philosophers. The issue arises with the fact that, if the past is fixed, and a time traveler wasn’t in the past and then later in the future travels there, he has then changed the past by merely being there because he there wasn’t before. Dowe proposes a solution to this paradox by explaining that there are not in fact two different pasts (temporal timelines), but instead that if the time traveler had traveled to the past then he had always been in the past.  This discussion goes deep into the realm of reverse causation, which assumes that future events can cause past events. The film 12 Monkeys does a great job of showing the complexities of reverse causation by showing the main time traveler causing events that lead to future ones. The concepts that surround reverse causation are very complex, but Dowe presents a logical argument that once again aids in the disassemblement of Grey’s argument.

               Although Dowe helps to revive the hopes of time travel in the face of the no desitantion paradox, there are still protests and questions of the logic of various aspects of his objections, especially those dealing with reverse causation. Over all, Dowe presents several flaws and weaknesses in theparadox and Grey’s argument so that the prospect of time travel may still flourish in our imaginations for years to come.

The Case for Time Travel, Phil Dowe, Philosophy, Vol. 75, No. 293 (Jul., 2000), pp. 441-451, Published by: Cambridge University Press on behalf of Royal Institute of Philosophy

          Time travel has been in the imaginations of some of our most creative thinkers for many years. Over time, our fascination with previewing the future and visiting the past has been tested by several paradoxes. One such paradox is that of the “no destination” argument. The argument is articulated by William Grey in his article “Troubles with Time Travel,” with his main argument being that a destination must exist for travel to be possible and according to a popular view that the past is fixed and the future is not yet existing, time travel is impossible. Phil Dowe, in his article “The Case for Time Travel,” comes to the rescue and presents flaws within Grey’s argument which help break the paradox of no destination. He presents the weaknesses in Grey’s presentation of the no destination paradox by showing that it doesn’t imply time travel is impossible in the Heraclitean view and that it lacks the ability to be applied to all theories of time and stay valid due to Grey‘s confusion between changing and causing the past. Dowe’s objections to Grey’s challenge to time travel allows for the hopes and wishes of time traveler supporters to remain alive.

               Grey presents the no destination argument through the Heraclitean view that only the present is real and that the past and future do not have eternal existence. This view of time is more popularly known as Presentism. From this view it is logical to understand his argument through the premises that “time travel is possible only if a destination exists, the past and future do not exist, and therefore time travel is impossible.” Although he follows the view that the past and future do not exist, he also presents an argument for the block theory of time (that the past exists yet fixed and unchangeable and the future is open and not yet existing) which follows that “if travel to the past were possible, the traveler could change the past, the past is fixed and unchangeable, and therefore, travel to the past is not possible.” His arguments presented in this light are logical, yet there are flaws that can be found within the premises which can leads to its unsoundness.

               Dowe responds to the no destinations paradox by first touching upon the fact that it doesn’t matter that the destination doesn’t exist when you depart, but that it exists when you arrive. He uses the analogy of waiting for tomorrow to demonstrate how although tomorrow does not yet exist, at some point we arrive at that tomorrow, which then would not rule out traveling to something that does not exist. I think a better argument can be constructed by focusing on tomorrow becoming today or in other words the future becoming the present which then exists. As the time traveler travels into the future, the future becomes his present and therefore his destination exists, but this destination only exists when he arrives (when it becomes his present) and not when he departs, according to the presentists perception of time. With these arguments, we can successfully show that there is nothing paradoxal about time travel into the future in the

Heraclitean or Presentist view.

               Dowe’s second point comes from Grey’s lack of applying the no destination paradox to other conceptions of  time, primarily the Parmenidian perception of time. The Parmenidian perception of time views the past, present and future as eternal truths which are fixed. Interestingly enough, in this case, it seems as though this view of time would support Grey’s argument, but Dowe objects to this by drawing upon the difference between changing and causing the past or future.

               The discussion on changing and causing the past is viciously explored by many philosophers. The issue arises with the fact that, if the past is fixed, and a time traveler wasn’t in the past and then later in the future travels there, he has then changed the past by merely being there because he there wasn’t before. Dowe proposes a solution to this paradox by explaining that there are not in fact two different pasts (temporal timelines), but instead that if the time traveler had traveled to the past then he had always been in the past.  This discussion goes deep into the realm of reverse causation, which assumes that future events can cause past events. The film 12 Monkeys does a great job of showing the complexities of reverse causation by showing the main time traveler causing events that lead to future ones. The concepts that surround reverse causation are very complex, but Dowe presents a logical argument that once again aids in the disassemblement of Grey’s argument.

               Although Dowe helps to revive the hopes of time travel in the face of the no desitantion paradox, there are still protests and questions of the logic of various aspects of his objections, especially those dealing with reverse causation. Over all, Dowe presents several flaws and weaknesses in theparadox and Grey’s argument so that the prospect of time travel may still flourish in our imaginations for years to come.

The Case for Time Travel, Phil Dowe, Philosophy, Vol. 75, No. 293 (Jul., 2000), pp. 441-451, Published by: Cambridge University Press on behalf of Royal Institute of Philosophy