talking point

noun

1. A specific topic raised in a conversation or argument which is intended as a basis for further discussion, especially one which represents a point of view.

   “Such an expression ["natural rights"] is, of course, an excellent talking point as a basis for argument to convince people, and perhaps through them to change the opinion of the government.”

   ““Something attempted, something done, has earned a night's repose. You have the satisfaction of having sacrificed yourself in the interests of [your uncle].” He had found a talking point. He had reminded me of those postal orders, sometimes for as much as ten bob, which Uncle Tom had sent me in the Malvern House days. I softened. Whether or not a tear rose to my eye, I cannot say, but it may be taken as official that I softened. “How right you are, Jeeves!” I said.”