We noted last time that on his first trip to the past Tim entered the closet, traveled to the previous night's party, undid his embarrassment, then went back into the closet and leapt back to the future. What is significant in this is that he changed his own history, but he did not live through the altered version of history; on the other hand, he was present for the altered version, and did live through it. His father is unaware when he begins to tell Tim of his ability that he has done this already, a different version of Dad having talked to a different version of Tim from the one who has, sequentially speaking, already left from the future, altered the past, and returned to the future a few minutes from now. The Tim to whom he gives the speech is equally unaware of this. Neither of them have any memory of Tim's embarrassment of the previous night (a problem we addressed last time). It is not certain what that other Tim remembers about the party. Clearly he does not remember having had this conversation with his father this morning, because for him this is the first time through.
Again as noted, we do not know where this Tim went to test the ability. However, that other Tim returns. He remembers living through the party twice, once as an embarrassing disaster and then again corrected. However, he will only have remembered going to bed once, awakening once, talking to his father once, and going to the closet to test the ability once. Meanwhile, there is--or until this moment was--a version of him who does not remember any embarrassment at the party, remembers going to bed last night and getting up this morning, having a conversation with his father which was not in the least tinged by his recollections of the embarrassment of the previous night, and going to the closet to make a trip somewhere to alter the past in some way that our Tim did not consider. What is particularly significant is that this doppelganger Tim was certainly thinking something that morning, and since our Tim was thinking about an embarrassment which that other Tim never experienced, the other Tim was thinking about something different.
So we come to the issue at hand, which is what our Tim remembers of the life of the other Tim. We get the answer eventually, that he has no memory of the events that he skips when he leaps forward in time; but then, where do those memories go? What becomes of the version of Tim that lived through those moments?
That issue becomes more significant in later trips, but it is already present here.
We confront our next issue with our next trip, when Tim goes back to talk to that gorgeous girl who visited over the summer, Charlotte.