Ernst Katz was one of the foremost teachers of anthroposophy in America during the second half of the twentieth century. He was professor of physics at the University of Michigan and, quite likely, the only professor in the country who taught courses in both natural science and spiritual science at the university level. He and his wife Katherine fostered the growth of anthroposophy in Ann Arbor and ultimately enriched the spiritual lives of people from coast to coast.<BR><BR>In the early 1960's, Dr. Katz began writing his response to the many questions he was asked through the years. His teaching essays were intended to help students comprehend the profound wisdom contained in the major works of anthroposophy. He became a master at writing explanatory guides for some of the most important spiritual-scientific concepts, demonstrating complex esoteric ideas in terms of clear analogies and taking examples from everyday life.<BR><BR>Core Anthroposophy makes available all of Dr. Katz's carefully constructed teaching essays, offering students of anthroposophy a valuable and accessible resource for better understanding the esoteric teachings of Rudolf Steiner.