In 1929, Karl Mannheim listed one of the tasks of the sociology of knowledge as solving “a problem which has always gone unanswered:. . . why we have not yet witnessed the development of a science of politics”. “In a world which is permeated by a rationalistic ethos, as is our own”,—he went on-“this fact represents a striking anomaly” (Mannheim 1997, p. 98). What the Hungarian-German scholar saw as the prime requirement in developing a scientific approach to the study of politics was a “new realism”, enabling one to recognize when thought is being socially conditioned and how partial all knowledge is (ibid., pp. 103ff). In considering the scope for a science of politics, Mannheim was following a tradition whose earliest roots lay in secular humanism, modern rationalism, the Enlightenment, and late-nineteenth-century positivism. To put it more exactly, Mannheim was enlarging on an issue that had been tackled by some of the leading lights of western political thought-from Machiavelli to Weber, taking in Hobbes, Montesquieu, and Tocqueville-that politics was fluid in nature and followed patterns of its own. It was such authors that gave rise to the modern idea that laws must be drawn up to enable politics to be “scientifically” grasped on a rational basis. Behind Mannheim’s concern one sensed, even at the time, an urgent practical need, born of the dramatic times he lived in. For contemporaries saw their age as radically different from the past; men of culture and science felt a duty to help the common cause of managing the change unfolding before their eyes (Blomert 1999).