Your best bet may be to attend the presentation, ask pertinent questions, and form your own opinion. You may want to do some Internet research ahead of time to help form your questions. Many revere him, and some also feel he wandered too far into Eastern philosophy. My own belief is that his Eastern interests have been unfairly overstated with the goal of questioning his orthodoxy. Many also feel his earlier works are more “solid” than his later ones. A complex man, to be sure, and one who struggled with his vocation towards the end of his life.