**A man could not always be where he belonged, though.** (George RR Martin, Game of thrones, Eddard,p117) and this one (my suggestion): *A man can not always be where he belongs, though.* (appears more acceptable to me)

I cannot understand why Martin used a past tense for a fact! If it is a fact -and it seems like a fact that we cannot be where we belong at all times-, shouldn't he be using a present tense? Can anybody explain this to me please?