When a philo­sopher deals with another philo­sopher or philo­sophy, his or her stance is never the one of dia­logue, but always the one of divi­sion, of draw­ing the line that sep­ar­ates truth from fals­ity – from Plato whose focus is the line that divides truth from mere opin­ion, up to Lenin obsessed with the line that sep­ar­ates mater­i­al­ism from ideal­ism. The courses are an exer­cise in this art of delim­in­a­tion: their aim is to spe­cify the con­tours of the dia­lect­ical-mater­i­al­ist notion of neg­at­iv­ity by draw­ing a line that sep­ar­ates it from other forms of thought of neg­at­iv­ity