Board Thread:General Discussion/@comment-26173711-20160917200205/@comment-4560646-20161125210354

Mabian wrote: I don't follow. Sans presumably knows about Chara because he is trying to stop the anomaly, but he specifically says that he has sort of given up because he knows that his own actions don't matter, so long as there is another being that can just reset things. But this doesn't actually get us to the conclusion that Sans knows about Chara. He just knows that there is an anomaly causing disruptions to the timelines until suddenly everything ends. The initial reading of those lines suggests that he is talking about Frisk as the anomaly, not Chara. What specifically suggests that Sans is aware of Chara? The Anomaly is just Sans' way to refer to whomever is manipulating the timeline. For a big time it was Flowey, and afterward it was usurped by Frisk. Or technically Chara, since the save file is under their name, but Sans only sees Frisk and not Chara, and in Undertale's timeline he's never directly met Flowey - only heard of him from Papyrus - so to Sans the anomaly is just Frisk.

There's no way for Sans to know about Chara outside of history books - and even then, there's no incentive for him to connect Frisk with the kid who died a long time ago.