Having discussed basic concepts necessary for tragedies in the previous chapters. Aristotle now turns to four more concepts necessary for the plots of tragedies to function.
1). Astonishment – this refers to the pity and fear the tragedy is able to inspire in the audience. Though it is a surprise, the tragedy must feel like part of a larger design and not chance events, i.e. it must relate to the tragic flaws of the hero.
2). Reversal – the events of the tragedy come full circle.
3). Recognition – usually linked with reversal, the hero learns of the tragic reversal and the audience feels pity and fear they might have similar flaws.
4). Suffering – not only must the hero suffer, the suffering must produce catharsis (Aristotle uses the term purgation) in the audience so that they fear they may have similar tragic flaws and befall similar tragic fates.
The best tragedies have all these elements.