This essay deals with the issue how to obtain a wider understanding regarding the value of critical thinking and dialogue in philosophy teaching at upper secondary school? This main question has been investigated with the guidance of Hannah Arendt. The conclusion is: Critical thinking and dialogue is a prerequisite for knowledge and knowing. The essay also deals with reasons why critical thinking and dialog no longer can be carried out in everyday schooling. The answer is that schools in Sweden slowly have been transformed into a commercial market, where customer satisfaction and the loyalty to the powers- that- be, and in many cases profitability are driving values. During the corresponding period, the teacher's practical professional skills have been degraded