What does Scrooge say has caused him to see the Ghost?

Scrooge believes that his own past misdeeds and the weight of his selfishness have caused him to see the Ghost. He recognizes that his life choices and the way he has treated others have led to this haunting experience. The visitations serve as a catalyst for his transformation, urging him to reflect on his actions and seek redemption. Ultimately, Scrooge understands that the Ghosts are manifestations of his conscience, compelling him to change.