In The Security Principle, French philosopher Frederic Gros takes a historical approach to the concept of "security", looking at its evolution from the Stoics to the social network. With lucidity and rigour, Gros's approach is fourfold, looking at security as a mental state, as developed by the Greeks; as an objective situation and absence of all danger, as prevailed in the Middle Ages; as guaranteed by the nation state and its trio of judiciary, police and military; and finally "biosecurity", control, regulation and protection in the flux of contemporary society. In this deeply thought-provoking account, Gros's exploration of security shines a light both on its past meanings as well as its present uses, exposing the contemporary abuses of security and the pervasiveness of it in everyday life in the Global North.