Depends on which model for backwards time travel is used, it's e.g. consistent with the "you always travel back to a parallel timeline, never to your own past" which has as a consequence that your presense may alter the time after your arrival without making a contradiction because it's happening to another timetime that the one you came from so you aren't altering your past, in which case he may have known his history, but that isn't the one he's in.
Originally Posted by Fortis
Reductionist and proud of it.
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