I must do something." "That's another story," I replied.

"Let us by all means weigh what is to be done.

But let us begin by putting the law-courts out of the question.

Don't forget that you are challenged to mortal combat.

Let us consider how the challenge should be met, but we won't fight under Queensberry rules because Queensberry happens to be the aggressor.
Don't forget that if you lose and Queensberry goes free, everyone will hold that you have been guilty of nameless vice.