Essays and Lectures is wonderful collection of non-fiction prose pieces by Oscar Wilde. It contains the following preface: HISTORICAL criticism nowhere occurs as an isolated fact in the civilisation or literature of any people. It is part of that complex working towards freedom which may be described as the revolt against authority. It is merely one facet of that speculative spirit of an innovation, which in the sphere of action produces democracy and revolution, and in that of thought is the parent of philosophy and physical science; and its importance as a factor of progress is based not so much on the results it attains, as on the tone of thought which it represents, and the method by which it works.