Just for reference since a lot of people get this backwards as you did, i.e. is Latin for "which is to say" (literally id est, "that is"), while e.g. is Latin for "for example" (literally exempli gratia, "free example"). There is another cousin which doesn't get so much use, namely viz., literally vide licit or "clearly seen", which is a sort of drop-in replacement for "namely" -- it's used to enumerate or clarify an indirect reference, as opposed to id est which clarifies an indirect implication.