The human body is a remarkably poor liar. The mouth can construct any narrative it chooses, but the limbic system, which governs the body’s stress responses, autonomic reactions, and behavioral outputs, has no access to the script. It responds to the psychological reality of the moment: the stress of fabricating, the anxiety of being caught, the discomfort of maintaining a false account under scrutiny, the physiological activation of concealing information that carries emotional weight. These responses leak continuously into behavior through channels that most people neither monitor nor control, because they are entirely unaware that the leak is occurring. The...