When the writer who started the conversation asked Rossio to “please never come on my feed with the n word again,” Rossio doubled down, arguing in a thread that the stigma faced by African-Americans is similar to that faced by those who refuse to vaccinate their children out of scientifically discredited fears of autism.

Rossio’s many critics—the tweet had more than a thousand replies—included fellow screenwriter Jeffrey Grubb, who responded acidly: “God, this is such a good point. I remember how American founders and citizens enslaved vaccine skeptics for decades. And then, even after freeing them, the government enshrined laws to marginalize vaccine deniers and to deny them wealth and opportunity. That’s just history.”

Another Twitter user replied to Rossio with the announcement that his comment inspired him to donate $25 to a nonprofit that vaccinates children around the world.