After a review of the manifold phallic symbolisms, with their ambivalence of longing and fear, in ancient mythologies, the writer discusses their appearance in our present culture. A case is presented of a patient who had a fanatic preoccupation with 'truth' and 'knowledge'. Dreams and fantasies, in part reminiscent of the antique symbols, showed that knowledge represented his phallic sexuality which was greatly inhibited by castration fear. The writer arrives at the conclusion that as civilization progressed and interest shifted from gods and demons to abstract forms of learning and knowledge, 'progress', 'truth' and 'knowledge' have become enshrined as modern gods, and that it is possible that these abstractions are basically refined phallic symbols.