He wouldn’t have killed someone just to save Derwatt Ltd. or even Bernard, Tom supposed. Tom had killed Murchison because Murchison had realized, in the cellar, that he had impersonated Derwatt. Tom had killed Murchison to save himself. And yet, Tom tried to ask himself, had he intended to kill Murchison anyway when they went down to the cellar together? Had he not intended to kill him? Tom simply could not answer that. And did it matter much?
— from Ripley Under Ground, by Patricia Highsmith.
It’s the “Tom supposed” and “Tom tried to ask himself” that I find most chilling. He doesn’t ask himself. He tries to ask himself.