At one point in “The Metaphysical Club,” Menand observes that even such luminaries as Ralph Waldo Emerson would read books for any insight and stimulation they might offer, and abandon efforts at complete comprehension. That is the way I had to read this book. It has far too much happening for me to fully comprehend, but I found it delightful to listen to. The ideas are stimulating, the characters are inspiring, and the writing is luminous.