Scrooge is surprised to find out that the dead man is future Scrooge.

Scrooge is a very different person at the end of the Stave 4.  He has begun to reform.  As the Ghost of Christmas Yet to Come takes him to see the reactions to this poor man’s death, he does not realize that it is himself.  When Scrooge finally asks who it is, he is shown a headstone with his own name on it.  This shocks him.

“Am I that man who lay upon the bed?” he cried, upon his knees. (Stave 4, p. 50)

At this point, Scrooge is even more anxious to repent and reform.  He swears to “keep Christmas” in his heart, and he a good person.  The ghosts would not have bothered to show him these things if he was past hope, he figures.

I will not shut out the lessons that they teach. Oh, tell me I may sponge away the writing on this stone!” (Stave 4, p. 51)

At this point, Scrooge returns to the world of the living and realizes it is Christmas Day.  He does change, and becomes a good person.  He does not forget the lessons taught to him by the three ghosts.  Because of his intervention, Tiny Tim does not die and neither does Scrooge—for a good long while.

This chapter is an excellent example of dramatic irony, because we know that the man is Scrooge, but Scrooge does not.  We realize that he is still basically the same person, but he thinks of himself as reformed already.