This piece addresses the question “how has architectural theory changed over time?” In particular, it explores the longue durée of two millennia of architectural writings in the west. In doing so the piece addresses the historicality of architectural theory in the western tradition. It asks what the big paradigm changes are that architectural theory has gone through, how it was different in earlier centuries to now, and whether there are different genres, formats, media, or dominant questions and problems that have defined it in different epochs.