Getting into it with someone whose best response to the phrase "Black Lives Matter" is "All Lives Matter" may seem no more appealing than banging one's head against the wall. But one man pieced together the perfect response, and his Facebook post about it is going viral.

Actor Lee Edward Colston offered a play by play of the conversation that ensued after an "older white guy" on the subway approached Colston about his Black Lives Matter T-shirt.

"Why do black people get offended when we say All Lives Matter?" the man asked.

Colston, noticing the man was reading a book about climate change, challenged the man's insistence that global warming was "the most important issue of our generation."

Colston listened, and then countered back: "All planets matter."

"That's not fair," the man said. "It's not the same thing. Because it completely dismisses the fact that... Oh..."

That's a lightbulb moment, folks.