Esoteric knowledge is one of those things that sounds very cool—that word, “esoteric”—but for most of us lacks a clear definition. It conjures up the mists of the East, ancient riddles, dark secrets, and the promise of ultimate power—all things that entice many contemporary human beings, because, whatever esoteric knowledge is, it seems that an exciting offer is on the table. As with most offers, however, what is really on the table is a transaction. So, to assess esoteric knowledge, we need to know not only what we are allegedly getting, but what we are trading away!