Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Augustine of Hippo remains one of the most prominent and influential figures in the world of Catholicism, famous for his many writings and sermons on Catholic Christianity as well as his ardent defence of it. His debate with Fortunatus, a member of the Manichaean faith presented Augustine with one of his defining moments as a member of the Catholic clergy. This is because Augustine had only been a presbyter in the Church at Hippo for a few months when this debate took place and therefore had much at stake against his wily opponent. To make matters even more complicated for Augustine, he himself had been a Manichee for at least nine years and knew Fortunatus as a skilled debater. But rhetoric, or the art of persuasion, was a field in which Augustine excelled, having both a natural proclivity for speaking as well as the formal education behind it. Chapter one begins with an introduction to the debate, the primary characters, and the religions involved. Chapter two continues with an exposition of Augustine and his association with Manichaeism and then goes on to describe Augustine‟s anti-Manichaean works. From this point, chapter two continues with a section on Manichaeism, its spread, its myth and its practice. From this contextual basis, chapter three deals with the methodology of Critical Discourse Analysis and the three most important characters in the form of Halliday, Fairclough and van Dijk. This chapter is followed by another chapter on theory: Argumentation Theory. Chapter four includes subsections on van Eemeren and his methodologies of Pragma-Dialectics and Strategic Maneuvering. The analysis chapters of this dissertation begin with chapter five which deals with concepts from Critical Discourse Analysis and Argumentation Theory. This chapter includes subsections on categories of enquiry, followed by a section on a number of recurring devices, namely: answering questions, changing the topic and quoting scripture. A Critical Discourse Analysis section follows with subsections that include difference, evaluation and knowledge as a common ground component of contexts. This in turn is followed by sections on Argumentation Theory and Strategic Maneuvering, which include subsections on economy, efficacy and coherence; realism and wellfoundedness; logical reasoning process and pragmatic inferences; reasonableness versus effectiveness; the rhetorical perspective; discussion strategies; dialectical aims versus rhetorical aims and deceptive manoeuvring. The final analysis chapter, the Contra Fortunatum in context, includes subsections on the opening of the debate, the structure of the debate and the topics of discussion. Within this last section subsections on the Nebridian conundrum, the origin of evil, and free will occur. The next subsection dicusses topics not mentioned in the debate: the Manichaean myth, Mani and the previous friendship between Fortunatus and Augustine. Following this there are sections on Manichaeism presenting itself as a form of Christianity, the debaters talking past each other and the issues of audience composition and power relations between the various role players. Chapter seven takes a concluding look at the issue of who should be designated the winner of the debate. / AFRIKAANSE OPSOMMING: Augustinus van Hippo bly een van die mees prominente en invloedryke figure in die wêreld van die Katolisisme, bekend vir sy vele skrywes en preke oor die Katolieke Christendom sowel as sy ywerige verdediging daarvan. Sy debat met Fortunatus, ʼn lid van die Manichese geloof, het aan Augustinus een van die bepalende oomblikke in sy rol as Katolieke geestelike besorg. Die rede hiervoor is dat Augustinus ten tyde van die debat nog net ʼn paar maande ʼn presbiter in die kerk in Hippo was; daarom was daar baie op die spel in die debat teen hierdie gedugte opponent. Om dinge selfs nog meer ingewikkeld vir Augustinus te maak, was hy self vir ten minste nege jaar 'n Manicheër en was hy bekend met Fortunatus se retoriese vermoëns. Retoriek, of die kuns van oorreding, was egter 'n veld waarin Augustinus uitgeblink het. Hy het beide ʼn natuurlike aanvoeling vir redevoering sowel as ʼn formele opleiding gehad. Hoofstuk een van die proefskrif begin met ʼn inleiding tot die debat, die hoofkarakters en die gelowe wat betrokke is. Hoofstuk twee gaan voort met ʼn uiteensetting van Augustinus en sy assosiasie met die Manichese geloof en beskryf ook Augustinus se anti-Manichese werke. Van hier af gaan hoofstuk twee dan verder met 'n afdeling oor die Manichese geloof, die mitologie en lewenswyse, sowel as die verspreiding van die Manicheïsme. Met hierdie kontekstuele agtergrond as basis handel hoofstuk drie oor die metodologie van Kritiese Diskoersanalise en die drie belangrikste eksponente van hierdie teoretiese rigting, Halliday, Fairclough en Van Dijk. Hierdie hoofstuk word gevolg deur nog ʼn teoretiese hoofstuk wat handel oor Argumentasieteorie. Hoofstuk vier sluit onderafdelings in oor Van Eemeren en sy metodologieë van Pragma-Dialektiek en Strategiese Maneuvers. Die ontledingshoofstukke van hierdie proefskrif begin by hoofstuk vyf wat handel oor Kritiese Diskoersanalise en Argumentasieteorie. Hierdie hoofstuk sluit onderafdelings in oor kategorieë van ondersoek, opgevolg deur ʼn gedeelte oor 'n aantal herhalende tegnieke: die beantwoording van vrae, die verandering van die onderwerp en skrifaanhalings. ʼn Volgende afdeling oor Kritiese Diskoersanalise volg daarop met onderafdelings wat verskil, evaluasie en kennis as ʼn gemeenskaplike komponent op die terrein van konteks insluit. Hierop volg 'n afdeling oor Strategiese Maneuvers. Laasgenoemde sluit onderafdelings in oor ekonomie, doeltreffendheid en koherensie; realisme en gegrondheid; logiese denkprosesse en pragmatiese gevolgtrekkings; redelikheid versus effektiwiteit; die retoriese perspektief; besprekingstrategieë; dialektiese doelwitte versus retoriese doelwitte en maneuvers van misleiding. Die finale ontledingshoofstuk, getiteld die Contra Fortunatum in konteks, sluit onderafdelings in oor die openingsreëls van die debat, die struktuur van die debat en tematiek daarvan. In die laaste afdelings word die kwessies van die Nebridiese vraagstuk, die oorsprong van boosheid en die vrye wil ingesluit. Die volgende onderafdeling bevat onderwerpe wat nie in die debat behandel word nie: die Manichese mite, Mani en die vroeëre vriendskap tussen Fortunatus en Augustinus. Daarop volg die afdelings oor die Manichese strategie om hierdie godsdiens as Christelike godsdiens voor te stel, die deelnemers se taktiek om verby mekaar te praat asook oor die samestelling van die gehoor en kwessie van die magsverhoudinge tussen die onderskeie rolspelers. Die laaste hoofstuk sluit samevattend af met 'n kort bespreking van die kwessie van wie as die wenner van die debat beskou moet word.