Your fund, Pershing Square Capital Management, took a $500-million loss on its investment in J. C. Penney. How did that feel?

I’m not emotional about investments. Investing is something where you have to be purely rational, and not let emotion affect your decision making — just the facts.

Where do you think the investment went wrong?

Look, investing is inherently probabilistic — not every investment is going to be profitable. We bought a big stake in the company at a price that we believed to be attractive. We worked with the board to help recruit who we believed to be the best retail C.E.O. in America, Ron Johnson, who opened the Apple stores. The execution wasn’t perfect, far from it. Turnarounds are tough.

Your stake in Target also failed. Will you ever invest in another retailer?

It would have to be a very special situation.

Your short position on Herbalife — you’re betting against the company — has caused some friends like George Soros and Daniel Loeb to turn on you.

Neither of the people you mentioned is, or has ever been, a close friend of mine. I certainly know the people you mentioned — but, look, you need a thick skin to be in this business. In a short sale, the whole world is going to be on the other side of the investment until they realize you’re right.