The term derives from th Greek word for 'place' and particularly from Aristotle's realisation that it is by associating ideas with places, or in groups, that we make sense of the world. For Aristotle it follows that rhetoric -- and we would now say discourses – works with particular configurations of words and meaning which become standard patterns of association and thus recognisable places for a culture. Obvious topoi may indeed be physical places, whether generalised (gardens, desert islands, bowers of bliss) or particular (London, Los Angeles), or they may be mental places, such as 'the Gothic house', 'romantic love' or 'Christian devotion' when these are seen as a kind of recognisable place in the mind.
Editors. "Topos". The Literary Encyclopedia. First published 01 November 2001
[http://www.litencyc.com/php/stopics.php?rec=true&UID=1126, accessed 20 June 2013.]