Richard Matheson said this quote

“ He took the woman from her bed, pretending not to notice the question posed in his mind: Why do you always experiment on women? He didn't care to admit that the inference had any validity. She just happened to be the first one he's come across, that was all. What about the man in the living room, though? For God's sake! he flared back. I'm not going to rape the woman!Crossing your fingers, Neville? Knocking on wood?He ignored that, beginning to suspect his mind of harboring an alien. Once he might have termed it conscience. Now it was only an annoyance. Morality, after all, had fallen with society. He was his own ethic.Makes a good excuse, doesn't it, Neville? Oh, shut up. ”