“Irritability,” from Latin irritabilis, irritabilitas (see also “sensibility” from Latin sensibilis, sensibilitas), is a medical description of the condition of the body with regard to its ability to respond to (external) sensory stimuli and to react to them. Abnormalities of irritability and sensibility were considered symptomatic of illness.
Around 1700, the Cartesian-mechanistic conception of life came in for increased criticism (Mechanism). …