A man's behaviour may be quite harmless and even beneficial, when he ismorally behaving like a scoundrel. And he may do great harm when he is morally acting on the highest principles.
When you want to put something into your part that is not in the play, you must ask the author-or some other author-to lead up to the interpolation for you. Never forget that the effect of a line may depend not on its delivery, but on something said earlier in the play, either by somebody else or by yourself, and that if you change it, it may be necessary to change the whole first act as well.
The utmost I can bear for myself in my best days is that I was one of the hundred best playwrights
in the world, which is hardly a supreme distinction.