(47) the Rhetorica ad Herennium

At first glance, and also from reading surveys of the medieval commentary on it, the Rhetorica ad Herennium memory system seems excessively difficult. To start with, one seems to have to be able to visualize a long colonnade, with every fifth or even every tenth space marked in some distinctive way. In the Palace of Charles V in Granada, the doors and niches behind the columns might help a little as reference points for counting off every fifth intercolumniation (space between columns), although not much. It does not seem as though having such a space nearby would help remember things.

But there may have been an easier way. In one of the Harry Bosch detective novels, there is a memorable scene where Harry Bosch and an unidentified person share a cigarette on the steps of a courthouse in Los Angeles.
(see the notes page for medieval commentaries and Harry Bosch novels)