The Four Horsemen are destructive behaviors in relationships identified by Gottman: defensiveness, stonewalling, criticism, and contempt. Among these, contempt stands out as the most detrimental. It signifies a deep-seated disdain for one's partner, which can erode the foundation of a marriage.
Gottman emphasizes that the presence of contempt is a critical indicator that a relationship is facing serious challenges. When one or both partners express contempt, it signals significant emotional disconnect and hostility, ultimately threatening the stability and health of the marriage.