In Act Three, Scene One, I was surprised at St. Clare's response to Tom's plea.
"Tom: Last night, between one and two, I thought so. I studied upon the matter then-- mas'r isn't good to himself.
St. Clare: Ah! not I understand; you allude to the state in which I came home last night. Well, to tell the truth, I was slightly elevated-- a little more champagne on board than I could comfortably carry. That's all, isn't it?
Tom: All! Oh! My dear young mas'r, I'm 'fraid it will be the loss of all-- all, body and soul. The good book says "it bitet like a serpent and stingeth like an adder," my dear mas'r.
St. Clare: You poor, silly fool! I'm not worth crying over.
Tom: Oh mas'r! I implore you to think of it before it gets too late.
St. Clare: Well, I won't go to any more of their cursed nonsense, Tom-- on my honor, I won't. I don't know why I haven't stopped long ago; I've always despised it, and myself for it. So now, Tom, wipe up your eyes and go about your errands."
-The first time I read this scene, I thought St. Clare was giving up something he really liked, and the quick way he gave it up made the scene less believable. How can someone so readily give up an addiction, and for a slave?
But in rereading the scene, it seems like alcohol isn't actually all that important to St. Clare, or Clare is just giving it up to make Tom feel better and just get out of the way.
Of course all of this can work and all of this can change depending on the actors' interpretation and presentation of the characters.