Seth Meyers got some help Tuesday from Late Night writer Amber Ruffin who popped in to explain to Megyn Kelly why her defense of wearing blackface on Halloween was, yes, racist. As we all know by now, during a segment on Halloween costumes on her NBC show yesterday, Kelly wondered, “What is racist, because you do get in trouble if you are a white person who puts on blackface at Halloween, or a black person who puts on whiteface for Halloween,” adding, “When I was a kid that was okay as long as you were dressed like a character.”

After taking a deep sigh, Ruffin calmly explained that “there is no magical day when you can wear blackface with no repercussions—unless all of your friends are white.”

Going on to relate the long and painful history of white people painting themselves up to mock black people, Ruffin patiently explained to Kelly, “Blackface is racist because it turns black people into a costume and divorces them from their humanity.” Ruffin also noted Kelly’s all-white panel of guests, and suggested having a few black people on her show might help.

Kelly issued apologies yesterday for her remarks, and again today at the top of her show, saying her defense of wearing blackface for Halloween “was wrong, and I am sorry.”

You can watch the clip of Ruffin above.