To develop students' critical thinking is one of the primary goals of a modern democratic school system. However, what is to be developed has been the matter of long-standing debate. One particular area of conflict has been what role is played by the knowledge concerning the object to be critically thought about. The 'specifists' have asserted that knowledge about the object is the core. The 'generalists' have claimed that there is no need for any actual profound knowledge. Typically, this debate has been held at a theoretical and philosophical level. In this paper, I will make an empirically based contribution to the debate. In a unique approach, I will use a number of student essay responses to argue in favour of a specifist view, and at the same time to question some of the generalists' basic assumptions. The paper ends with an appeal to the generalists to provide us with proper clarification regarding the questions I raise. This is important as they hold the dominant position in the field. If they are to continue to do so, we need to be clear about the accuracy of their basic assumptions. This becomes even more essential as the generalist research has been severely criticised for producing inconclusive results, as well as the fact that the generalist view on critical thinking has been adopted by major policymakers both in Europe and the United States.