Not like that time I confused a human and an Orangutan.
"What did you call me?" he said.
"Orangutan, hide! Before the humans learn you can speak their language!" I said. Then he started hiding, then remembered "wait, I'm the human". It took him about 40 minutes. Finally, he came out of the closet and said, "Hold on..." Then he thought about it for another 40 minutes, twisting his face in a grotesque parody of thought.
I left. I knew he'd be mad. Humans are sensitive about being called anything they're not - orangutan, ape, piece of shit - even if you mean it as a compliment.
He sent me an e-mail later that week saying,
NOT! U r NOT dear to me at all!!!!11
Peter Voser, Chief Executive of Shell Oil