You can't win with a racist. But I'm trying anyhow: Could I get a little help here?

[Max Blair]

Hi. I am mildly autistic. I don't really understand how the world works. I have this friend, also mildly autistic, who believes that the overwhelming weight of peer reviewed science, most evident by the work of the late Canadian JP Rushton, decisively proves that black people are, on the average, substantially less intelligent than white people. She believes that the reason for this has been proven by Rushton to be because they have smaller brains. Yeah, I know. You can't win with a racist. I know the smart thing to do is just unfriend her, walk away, cut my losses, and blah blah blah. But hell, I haven't made a new friend that's stuck in years. I don't like to give up. This is kind of a last ditch deal here.

What would you say to my friend?