Those who have engaged with psychopaths or narcissists often retroactively report having had an initial feeling that something was off, but they did not heed it. Some actually said that they felt queasy or sensed a coldness in the individual, but brushed it aside because they wanted to like the person or were flattered by his attention.
Neither a perfectly-crafted mask nor the world’s most charming repartee can fully camouflage a lack of emotional empathy, which is the defining hallmark of both psychopathy and narcissism. A person cannot wholly fake that which they do not experience, even if they say and do “all the right things.” So while your conscious mind focuses on an individual’s statements and conversational style, your subconscious registers possible discrepancies between that person’s outward comportment and his hidden feelings. Stay attuned to both avenues of information if you suspect you are in the presence of a person who wants to manipulate you, or who is nothing like the entity they are conjuring in conversation.