Abstract
A fundamental part of every critic to knowledge, in the scope of Western Philosophy, has consisted of investigating on the conditions of its own possibility, on what it is that makes achievable the spread of cognitive activity. From a philosophy that had as its main concern the investigation of life as a biological phenomenon, Georges Canguilhem developed a thought that may well be characterized as a "critique of the medical reason," whose central question was to know what is that makes possible the knowledge of life, his conclusion was that it is only from sickness and the pathological condition that life can become the object of science. But this commitment is not without precedents, in Plato himself is already possible to find such intuition, but especially in some modern thinkers such as Adam Smith, David Hume and Auguste Comte where Canguilhem found some ideas to sustain his own theory, namely, that it is in the pathos where one can find the condition of logos, conclusion that not only will have important epistemological consequences, but also a valuable ethical resonance.