Who is horwitz and what does Holden argue with him about

Horwitz. Holden argues with Horwitz, a cab driver, on his way to Ernie's. In the cab to Ernie's, Holden chats with Horwitz, the cab driver. He asks what happens to the ducks in Central Park during the winter, but the two get into an argument when Horwitz thinks that Holden's questions are stupid.