Egon Spengler him, which leaves him a little flustered. He celebrates his 40th birthday during this series, which would put him in his late twenties when "The Real Ghostbusters" began. Age is the largest factor causing Spengler to having transition from active ghost hunting to a mentorship role; in one episode where the original Ghostbusters guest starred on an episode the audience clearly sees middle adulthood has affected the speed and weakened the stamina of the original Ghostbusters. Although Egon Spengler does not appear in the 1990 "The Earth Day Special", his character and status as a Ghostbuster is mentioned, and Harold
Oswald Spengler while Karl Popper called the thesis "pointless". 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. Ludwig Wittgenstein, however, shared Spengler's cultural pessimism. Spengler's work became an important foundation for the social cycle theory. In late 1919, Spengler published "Prussianism and Socialism" ("Preußentum und