Tourette's syndrome slip

John Davidson, who has Tourette's syndrome, said the taboo word "nigger" with no conscious intention while two blacks were on stage. People freaked out. A few decades ago, antiracists understood the word as an unjust insult &mdash; when it was meant to characterize someone. But people could contemplate the word in the abstract, and discuss its meaning and implications (such as, a racist attitude)…