A and Not-A

A Christian thinker may say, "Here is Subject A. What do you think?" The response is typically, "I am for A," or "I am against A." Coming from the side of philosophy, where one finds an A, one finds a not-A, which is the principle of contradiction, or the law of non-contradiction. The question now becomes, "This thinker discusses Subject A. What about Not-A?" Say, for instance, that the subject under consideration is some aspect of bioethics. What is the thinker's interest beyond it? The answer may reveal a lot about who the thinker is.