Erich Fromm: Everything Must Be Doubted

What is meant by radicalism? What does humanist radicalism imply?

By radicalism I do not refer primarily to a certain set of ideas, but rather to an attitude, to an "approach," as it were. To begin with this approach can be characterized by the motto: de omnibus dubitandum; everything must be doubted, particularly the ideological concepts which are virtually shared by everybody and have consequently assumed the role of indubitable commonsensical axioms.

To "doubt" in this sense does not imply a psychological state of inability to arrive at decisions or convictions, as is the case in obsessional doubt, but the readiness and capacity for critical questioning of all assumptions and institutions which have become idols under the name of common sense, logic, and what is supposed to be "natural." This radical questioning is possible only if one does not take the concepts of one's own society or even of an entire historical period - like Western culture since the Renaissance - for granted, and furthermore if one enlarges the scope of one's awareness and penetrates into the unconscious aspects of one's thinking. Radical doubt is an act of uncovering and discovering; it is the dawning of the awareness that the Emperor is naked, and that his splendid garments are nothing but the product of one's phantasy.
This was part of the introduction to a Ivan Illich's Celebration of Awareness. The full text can be found here.