 At the heart of the Topics is a collection of what Aristotle calls topoi, “places” or “locations”. Unfortunately, though it is clear that he intends most of the Topics (Books II–VI) as a collection of these, he never explicitly defines this term. Interpreters have consequently disagreed considerably about just what a topos is. Discussions may be found in Brunschwig 1967, Slomkowski 1996, Primavesi 1997, and Smith 1997.