How do smells shape friendship, aggression, and tears? Dr. Noam Sobel, a neurobiology professor at the Weizmann Institute, explains how odors influence hormones, emotions, and behavior, and previews digitized smell for medical diagnostics. Hosted by Andrew Huberman, this Essentials episode revisits research on click friendships, the smell of fear, and the chemical signals humans send each other, often without awareness. Sobel also describes his lab's work predicting odor similarity and generating smells from molecular mixtures. Humans sniff their hands after handshakes at high rates, and the behavior appears to compare self-odor with the other person's.