Though forbidden, fortune-telling, numerology, astrology, and other such practices were very popular in the Middle Ages. Popes were even said to have had their charts done.
Even though it was practiced, everyone knew it was a sin. You sinned if you went to a fortune teller. You were an even bigger sinner if you were a fortune-teller.
Know how these sinners are punished. It's actually a little bit funny, when you think about it.
Know that he encounters Tiresias. Know Tiresias' story as delineated in the footnotes.
