The movements and protests of 1968 worldwide criticized the traditional idea of normality. From the 1970s onwards, psychiatry and antipsychiatry became an ideological battleground centered on the boundaries between normality and madness. In this scenario, characterized by a deep cultural and political transformation within the Left, the traditional concept of rationality and its very connection with irrationality was called into question. As a consequence, the very ideal of reason was questioned. This paper will explore the debate on rationality, irrationality and irrationalism within the so-called anti-institutional psychiatry and its reception in the Italian New Left during the second half of the 1970s.; Pokreti i prosvjedi koji su se 1968. odvijali širom svijeta, kritizirali su tradicionalnu ideju normalnosti. Od 1970-ih nadalje, psihijatrija i antipsihijatrija postali su ideološko bojište usredotočeno na granice između normalnosti i ludila. U ovom scenariju, koji karakterizira duboka kulturna i politička transformacija na Ljevici, tradicionalni pojam racionalnosti i njegova povezanost s iracionalnošću dovedeni su u pitanje. Kao posljedica toga, doveden je u pitanje sam ideal razuma. Ovaj će rad istražiti raspravu o racionalnosti, iracionalnosti i iracionalizmu unutar takozvane antiinstitucionalne psihijatrije i njezinu recepciju na talijanskoj Novoj ljevici tijekom druge polovice 1970-ih.