Insincerity is one of the most important "emotions"/characteristics to recognize. We are all insincere from time to time (Does this outfit make my butt look big?). But chronic insincerity is a warning sign, perhaps of pathology. Chronic insincerity eventually will harm those who are close to "it" and you would be well advised to avoided. I don't mean to suggest that John Edwards is chronically insincere, but most of us would say that those who partake in a longstanding extramarital affair are certainly insincere.
Mr. Edwards displays a beautiful contracture of the central forehead. Such a sign is often seen when there is physical or emotional pain. In fact, if there is significant physical pain, this signal must be present. When there is emotional pain, it can be present when oneself or other is in pain. Emotional pain for others is an example of empathy. BUT THERE IS A WARNING SIGN HERE. Mr. Edwards displays a very slight smile in this image. A smile is INconsistent with any kind of pain, emotional or physical. So when these two facial signals are present at the same time, they exist in contradiction - THERE IS INSINCERITY PRESENT. Once again, it does not mean that the person as a whole is necessarily insincere, but in THAT MOMENT there is insincerity present. This combination of facial expressions is one of the surest signs of insincerity. When you see it displayed, take note of how much the person makes this expression. If you see it often - avoid him/her - in business and in your personal life.