Oh, really? One man's meat is another man's poison

Dr. John H. Watson:

Try some of this curry. It's excellent. Sherlock Holmes:
[ignoring him and speaking to the waiter]
Steak and kidney pudding, please. Major Duncan-Bleek:
Of course, the Bengal curry doesn't compare with that of Madras. It's the quality of the mutton that makes the difference, don't you think? Dr. John H. Watson:
The, uh... the meat's unimportant. It's the spices that make the difference. Don't you agree with me Holmes? Sherlock Holmes:
[he hasn't been paying attention to the discussion]
What? Dr. John H. Watson:
I say, we-we-we were discussing curry. Sherlock Holmes:
Oh, yes, curry! Horrible stuff! Dr. John H. Watson:
Oh, really? One man's meat is another man's poison