What does this statement imply "I can promise the one but not the other " from the Memoirs of Sherlock Holmes ("The Final Problem"), at this link:
"'...It has been a duel between you and me, Mr. Holmes. You hope to place me in the dock. I tell you that I will never stand in the dock. You hope to beat me. I tell you that you will never beat me. If you are clever enough to bring destruction upon me, rest assured that I shall do as much to you.'
"'You have paid me several compliments, Mr. Moriarty,' said I. 'Let me pay you one in return when I say that if I were assured of the former eventuality I would, in the interests of the public, cheerfully accept the latter.'
"'I can promise you the one, but not the other,' he snarled, and so turned his rounded back upon me, and went peering and blinking out of the room.
This got me thinking who or what could be the "one" and the "other" it's frustrating that even now I haven't been able to figure it out. Guys your aid is sought on this .