I love Ebenezer Scrooge!  He has one of the great "bum raps" in
English Literature, for he is shown now as who he was not who he
became.  This is what happened: Scrooge changed the future!  And
how did he do it? By changing the present.  Tiny Tim did not die, and
he would have.  Scrooge sponged away the writing on a stone.  Think
about the effort needed to erase a stone with a sponge. It can be
done; it will take a lot of sponges and a lot of rubbing and a lot of
time. Yet Scrooge did it.  If you want to change the future, change
the present. It will be hard and you may be laughed at. It's your
choice.

 Now listen to the terrified Scrooge at his own grave:

     "Before I draw nearer to that stone to which you point," said
     Scrooge, "answer me one question. Are these the shadows of
     things that Will be, or are they the shadows of things that May
     be, only? ... Men's courses will foreshadow certain ends, to
     which, if persevered in, they must lead. But if the courses be
     departed from, the ends will change. Say it is thus with what you
     show me!...

     "Spirit, hear me! I am not the man I was but for this
     intercourse. Why show me this if I am past all hope?... Assure
     me that I may yet change these shadows you have shown me, by an
     altered life! ...  Oh, tell me that I may sponge away the writing
     on this stone!"

     ....

     Scrooge was better than his word. He did it all, and infinitely
     more; and to Tiny Tim, who did NOT die, he was a second
     father ... Some people laughed to see the alteration in him,
     but he let them laugh ... [and] his own heart laughed: that was
     quite enough for him.