My essay A Streetcar Named (among Other Things) Proof in Circles Disturbed: The Interplay of Mathematics and Narrative (Princeton 2012), co-edited with Barry Mazur. In it, I make my case that logical-deductive proof was developed in classical Greece by the adaptation of narrative and poetic practices to the new environment of agonistic discourse in the public assemblies and courts of law. Strong evidence of such patterns is found in 5th and 4th-centyr BCE oratorical speeches and in early Greek deductive mathematics. A brief typology of these types of narrative/poetic-derived proofs in rhetoric and Euclid is presented. This paper focuses on the cognitive dimensions of this transformation. The historical investigation of the same thesis was developed with my colleague Michalis Sialaros (Birkbeck), and to be published as “Sing Muse of the Hypotenuse”, in the forthcoming volume Writing Science, (De Gruyter 2013) edited by Markus Asper.