The process is an indirect one in that there is no perception of madness other than by reference to an order of reason, and to the consciousness that we have when confronted with a man of reason, which can assure us of the coherence, the logic and the continuity that underlies his speech; that consciousness lies dormant until madness erupts, appearing all of a sudden, not because it has taken on a positive form but precisely because it is a kind of rupture.