If personal-identity is construed as a spatiotemporal wormhole that extends through time from the past to the present, then to have self-knowledge is to be able to know (to some degree) about the pasts that lead to the present time. While we form a narrative to connect these past events together to the present there is a potential discrepancy between our self-narrative and our persona-identity. There might be gaps in our self-narrative that does not account for past experiences or facts of our personal identity. This seems true but why does it pose a philosophical problem?
There is an analogy that is given between the personal identity and a train behind the warehouse. If I walk alongside with my friend near the train, at the one end of the train I exclaim "There is the train!" and as I walk through I end on the other end of the train and exclaim "There is the train!". A friend of mine, who tries to be clever, my retort "No Paul, that isn't the same exact train since it is only one cargo connected to the locomotive on the other end." I might respond "I never said that two ends of the train are the same, I said they are part of the same train". However, let's change this scenario a little bit: suppose that we walk across only to find a very long warehouse that blocks our view of the train. How do I know that both ends of the train are part of the same train rather than being separate? It seems that there is the gap (the warehouse) that makes it difficult to determine whether the parts are really separate or part of the same continuum.
That being the case, how can I know that one part of me that I simply do not remember (i.e. let's say, when I was four years old) is really part of the continuum of personal identity that I identify as "Paul"? Do I need a complete self-knowledge in order to justify that whatever part of me that I do not remember is really a part of me?
Monday, April 30, 2012
Sunday, April 29, 2012
Possible Incoherence of regressive time travel
In this short essay I will argue that regressive time-travel is incoherent in B-Theory of Time (Eternalism). In B-Theory of Time, time is seen as events that are related to each in tenseless terms such as before and after. If this is the case then let's posit the series of events in succession A, B, C, D, and E. B, C, D, and E are all after A, and conversely A is before all of them.
The pattern seems to be that events are either before events after them or after events before them. If this is the principle of temporal pattern that we accept for B-Theory of Time then it appears that regressive Time Travel seems impossible. Let me make an argument to show why this is the case.
Let's say that I use the time machine in event E which is way after event A. If what I do in E (using Time Machine) will afterwards get me to A, then what I do in E happens before I get to A. But if what I do in E happens before I get to A, then what I do in E happens before and after A at the same time. Because when I did use the time machine in event E that happens after A but it also happens before A at the same time. Therefore, what I did in event E happens before and after A. This would violate the principle of temporal pattern that events are either before events after them or after events before them.
What this would mean is that time travel conventionally understood is impossible in B-Theory of Time. However there is a way to reconcile this contradiction: a spatiotemporal wormhole that connects A and E together. But how does this reconcile the contradiction that E happens before and after A at the same time? This has to be understood in the principle of temporal pattern in which events are either after events before them or before events after them. E is an event that is after A but it is also an event that is before A even though it is also after A. So how does a wormhole solve this contradictory problem? There are two alternative explanation that can only be presented in the light of this question: is a wormhole an event?
This presupposes an assumption on what constitutes an event but let's assume that under B-Theory of Time an event is relational in so far as it is either before all other events after it or after all other events before it. Can a worm how be a event in so far as it is relational to all other events as before or after? Another alternative is that wormhole is not an event hence it is exempted from the principle of temporal patterns. I will argue against this alternative in favor of the argument that a wormhole is possibly an event:
The opening of the portal to the wormhole happens before the person cross through the portal through the wormhole. It seems that the tenseless relations "before" and "after" can coherently apply to the wormhole scenario. Let's instantiate this into X as opening the portal that leads to the portal and Y as going through the opened portal through the wormhole. X ipso facto is before Y and Y ipso facto is after X. So when I use a time machine in event E to go to A I go through the events X and Y in succession in order to get to A. So far so good since the temporal succession of X and Y is consistent with the principle, but does this reconcile the contradiction that E happens before and after A? One can argue like this: "What leads to event E is through the intermediates between E and A: B, C, and D. It is because of those intermediates that E is after A but not before A. These intermediates make it logically impossible for E to be also before A. However the use of the time travel in E leads to another intermediate such as X and Y. X and Y is a new intermediate that leads to A. So E happens before A through the intermediates X and Y and After A through intermediates B, C, and D. Therefore, there is no real contradiction in saying E happens before and after A."
So far this sounds like a very convincing response since both intermediates are consistent with the principle of temporal pattern so far. However I have a counter response to this argument: The intermediate X and Y happens after E and at the same time happens before A, which seems consistent with the principle of temporal pattern but there is a problem here: anything that happens after E also happens after A. If that is true then the intermediate X and Y happens after A and at the same time happens before A since they lead to A through time-traveling wormhole (X). Perhaps X itself counts as being a sub-part of E since it is within E that I open the portal before I time-traveled to A but what happens in Y, which is actually time-traveling through a wormhole (let's say mid-point) happens after E. If Y happens after E then it also happens way after A but at the same time Y happens before A since it leads to A. In a sense, the contradiction in E has transferred to the intermediate, more specifically Y.
If my counter-argument works here then it follows that regressive time-travel is still impossible in B-Theory of Time.
This presupposes an assumption on what constitutes an event but let's assume that under B-Theory of Time an event is relational in so far as it is either before all other events after it or after all other events before it. Can a worm how be a event in so far as it is relational to all other events as before or after? Another alternative is that wormhole is not an event hence it is exempted from the principle of temporal patterns. I will argue against this alternative in favor of the argument that a wormhole is possibly an event:
The opening of the portal to the wormhole happens before the person cross through the portal through the wormhole. It seems that the tenseless relations "before" and "after" can coherently apply to the wormhole scenario. Let's instantiate this into X as opening the portal that leads to the portal and Y as going through the opened portal through the wormhole. X ipso facto is before Y and Y ipso facto is after X. So when I use a time machine in event E to go to A I go through the events X and Y in succession in order to get to A. So far so good since the temporal succession of X and Y is consistent with the principle, but does this reconcile the contradiction that E happens before and after A? One can argue like this: "What leads to event E is through the intermediates between E and A: B, C, and D. It is because of those intermediates that E is after A but not before A. These intermediates make it logically impossible for E to be also before A. However the use of the time travel in E leads to another intermediate such as X and Y. X and Y is a new intermediate that leads to A. So E happens before A through the intermediates X and Y and After A through intermediates B, C, and D. Therefore, there is no real contradiction in saying E happens before and after A."
So far this sounds like a very convincing response since both intermediates are consistent with the principle of temporal pattern so far. However I have a counter response to this argument: The intermediate X and Y happens after E and at the same time happens before A, which seems consistent with the principle of temporal pattern but there is a problem here: anything that happens after E also happens after A. If that is true then the intermediate X and Y happens after A and at the same time happens before A since they lead to A through time-traveling wormhole (X). Perhaps X itself counts as being a sub-part of E since it is within E that I open the portal before I time-traveled to A but what happens in Y, which is actually time-traveling through a wormhole (let's say mid-point) happens after E. If Y happens after E then it also happens way after A but at the same time Y happens before A since it leads to A. In a sense, the contradiction in E has transferred to the intermediate, more specifically Y.
If my counter-argument works here then it follows that regressive time-travel is still impossible in B-Theory of Time.
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