I might allow different treatment of stuff for kids and stuff for adults, but I think I prefer to let the unadorned facts (or writings) speak for themselves. Some personal examples:

- In The Ballad of Black Tom, Victor Lavalle turns H. P. Lovecraft's most racist story ("The Horror at Red Hook") on its head, retelling it with a black protagonist. The most memorable thing about the book was that Lavalle dedicates his book "To H. P. Lovecraft, with all my conflicted feelings".

I wasn't aware when I first read Lovecraft in high school of how deeply racist he was. Anyone who isn't aware, as I wasn't, should read the article by Nnedi Okorafor, who won the World Fantasy Award a few years ago: http://nnedi.blogspot.com/2011/12/lovecrafts-racism-world-fa...

The Lovecraft poem quoted there is absolutely appalling. In her article, Okorafor says: "Do I want 'The Howard' (the nickname for the World Fantasy Award statuette. Lovecraft’s full name is 'Howard Phillips Lovecraft') replaced with the head of some other great writer? Maybe. Maybe it’s about that time. Maybe not. What I know I want is to face the history of this leg of literature rather than put it aside or bury it. If this is how some of the great minds of speculative fiction felt, then let’s deal with that... as opposed to never mention it or explain it away. If Lovecraft’s likeness and name are to be used in connection to the World Fantasy Award, I think there should be some discourse about what it means to honor a talented racist."

- I've been reading westerns the last few years, and (especially in the older works) see a lot of ethnic stereotyping and racism. I'm currently reading The Big Sky by A. B. Guthrie. The writing is brilliant - in the westerns I've read, the only writing as good has been Willa Cather's. Guthrie is a master of free indirect speech, and most of the narration is in that form. So the characters - mountain men of the 1830s - largely tell the story. But I don't have another book (out of over a thousand) where the "n-word" occurs as frequently - an average of maybe once every 3 - 4 pages. However ... there are essentially no black characters. It is almost always used by white characters to refer to other white characters, to Indians, or to themselves (the way we'd say "this guy" or "that guy").

A more general point is how you deal with someone who did good stuff but also held, say, racist views. Within reason, I think you should credit the good things but be honest about the bad. People will differ about what falls "within reason".

- I've enjoyed Ralph Waldo Emerson's essays since high school, and still enjoy reading them. He was progressive for his time, and staunchly anti-slavery. But I was disappointed when I saw some of his journal entries in which he denigrates black people, Irish, Indians, and Chinese.

- I took a course in existentialism and phenomenology in college. When we started the section on Heidegger, the professor (Izchak Miller, who later became part of the NetHack dev team) began by putting on the screen Heidegger's infamous statement made as rector at Freiburg. Miller said that, as a Jew, he was disgusted by Heidegger's Nazi sympathies, and that someone that smart should have known better. Nevertheless, he said that Heidegger was simply too important to be ignored, and that we would examine his philosophy - and that he left it up to us to think about how we would regard his moral failings.