Abstract
Starting from Canguilhem's remarks about normality and pathology, we analyze the ambiguities of the concept of mental health. Due to the little attention given to the understanding of individual sufferings by certain medical knowledge, we observe an increasing concern to measure, quantify and locate brain functions associated with unusual behaviour, states of anguish, learning problems or feelings of failure. The text of Canguilhem
The brain and the thought leads us to review the epistemological and ethical assumptions of current knowledge devoted to find the brain location of moral and intellectual functions; and it allows us to initiate a critical reflection about the axioms and presumptions of the science of the brain. Thus, taking as reference Canguilhem's reflections on the concept of health and on the history of sciences, we discuss the limits and difficulties of the quest to establish universal and objective parameters of mental health, begun in 1810.