Several times during the Revolution Maximilien Robespierre made reference to his physical frailty, of exhaustion and ill-health. Is it possible to identify more precisely the nature of his illnesses, and just when they occurred ? An analysis of his periods of illness and of absences from public life, in particular precisely when they occurred, is revealing. From his first great clash with a prominent Artésien noble in 1790, Robespierre was increasingly susceptible to periods of physical weakness, always correlated with political crisis.