The great historian of antiquity Eduard Meyer thought highly of Spengler, although he also had some criticisms of him. Spengler's obscurity, intuitionalism, and mysticism were easy targets, especially for the positivists and neo-Kantians who rejected the possibility that there was meaning in world history. The critic and aesthete Count Harry Kessler thought him unoriginal and rather inane, especially in regard to his opinion on Nietzsche. Philosopher Ludwig Wittgenstein, however, shared Spengler's cultural pessimism. Spengler's work became an important foundation for the social cycle theory.