Aristotle next addresses what elements comprise the 'best' tragic plots. First, a perfect tragedy should have a complex plan - thus using reversal and recognition to imitate actions which elicit fear or pity in the audience. And yet, a good tragedy does not simply present the spectacle of a virtuous man suffering adversity, for that is merely 'shocking' and does not make us empathize with the hero.
If pity is aroused by 'unmerited misfortune,' and fear by 'the misfortune of a man like ourselves,' then a good tragedy presents a character whose downfall comes because of a flaw in him - 'an error or frailty.' Though he is renowned, prosperous, even seeming virtuous, there is a chink in his armor that will inevitably be found - and will be the source of his demise.
Fear and pity truly can only be elicited through this tragic flaw in the hero which in turn is motivated by the 'unity' or spine of the entire piece. Some poets, says Aristotle, use spectacle to motivate fear and pity, but this ultimately does not resonate for long, since spectacle produces a different type of 'pleasure' than the one requisite for tragedy. Only pity and fear can produce true 'purgation' or emotions, rather than a spectacle of false catharsis.
Aristotle next summarizes the circumstances that make for good tragedy. First, it must involve incidents between people who are 'dear to one another' - i.e. a son killing a mother, a brother killing a brother, etc. There are all kinds of permutations of such an incident:
a. the act can be done consciously and with knowledge of the people involved (i.e. Medea slaying her children)
b. the act can be done ignorantly, and the tie of family or friendship discovered afterwards (i.e. Oedipus)
c. the act is not done, because the hero can't go through with it
d. the act is about to be done, but then the discovery reveals the true identities of the characters, and the deed is stopped before it does irreparable harm.
Aristotle points out that case c) is the least dramatic (though it works in Antigone), and that d) is likely the most effective.
When it comes to character, a poet should aim for four things. First, the hero must be 'good,' and thus manifest moral purpose in his speech. Second, the hero must have propriety, or 'manly valor.' Thirdly, the hero must be 'true to life.' And finally, the hero must be consistent.
The concept of 'true to life' is addressed further, and Aristotle points out that a well-drawn character acts out of 'probability and necessity,' not because of some arbitrary traits bestowed upon him by the author. Moreover, the unraveling of the plot comes from the actions of the plot itself - the inner logic of the chain of events, rather than the character himself. Indeed, a well-drawn character is simply in service of the plot.
Aristotle next lists the types of recognition available to a poet. First, there is recognition by signs - bodily marks, external ornaments like jewelry, or some other marking that delineates the secret identity of a person. Aristotle calls this type of recognition the 'least artistic type.'
Second, there is recognition 'invented by will,' or the sudden revelation of an identity without forewarning or necessity. This too, says Aristotle, is a type of device 'wanting in art.'
A third type is recognition from memory, where a character sees an object and it 'awakens a feeling,' and recognition from 'reasoning' provides a fourth type, where the character determines a secret identity through a process of deduction. Fifth is recognition involving 'false interference,' where a messenger or outside character facilitates the revelation.
But the sixth and best type of recognition is one that 'arises from the incidents themselves' and the discovery is made naturally in the course of the plot. Again, Aristotle points to Oedipus Rex as the model, since nothing in the construction of the revelation is artificial. It is simply a process of the plot's unravelling from the center, an essential core of the drama's unity.
Aristotle underscores the significance of recognition in this section, as a crucial element in producing tragic catharsis. As in other chapters of The Poetics, he creates a hierarchy of tools available to a poet in order to point out which type of recognition is 'best.'
Recognition by 'signs', though mocked by Aristotle, is clearly the most familiar to modern audiences. Indeed, most contemporary thrillers involve the discovery of a sign in the climactic 'twist' - either a marking on a victim's body, a hidden piece of jewelry, etc. (The Silence of the Lambs, for instance, depends on Clarice's discovery of a sign in the killer's house.)
Recognition by 'invention' might seem vague, but again it is a device that reappears often in contemporary work. In Seven, for instance, the villainous character, played by Kevin Spacey, has to announce the impending recognition so that the hero and audience can react - something that Aristotle, no doubt, would scorn, since it produces only fleeting pity and fear.
The best type of recognition arises when the entire narrative revolves around the given revelation - when it is an inevitable result of the beginning incident, even though the audience does not know it as such. A good contemporary example might be Alfred Hitchcock's Psycho, where the source of evil becomes clearer and clearer as the movie evolves - but never so clear enough that we can determine what it is until it is too late.
Remember that ultimately all these elements are leading towards catharsis - and it is the effectiveness of catharsis that demonstrates the power of the particular dramatic work. Catharsis may seem like a vague emotional construct, but it is a product of very deliberate plot choices (i.e. reversal and recognition.) As one critic notes, "If catharsis has anything to do with the emotional side of tragedy - and we cannot doubt that it has - then it, like the tragic emotions and the tragic pleasure, must be 'built into' the plot and thus made available to a reader in the same way, on the same terms, as it is to the spectator in the theater" (Else, 441).
It is also significant to note Aristotle's delineation of the tragic hero's character. The tragic hero is not an eminently 'good' man, or model of virtue swiftly brought down by adversity. In that, says Aristotle, there is only shock - since we can see none of ourselves in a perfectly virtuous man, and find it arbitrary that he would be selected for cosmic punishment. What is far more effective is if the hero possesses some 'frailty', or flaw (like Achilles' heel), which he compensates for, hides, runs away from - but eventually catches up with him. An 'error' of character should not be confused with an error in a character's 'action' - a tragedy must spin on a fundamental flaw in the hero's behavior and one that the audience can identify with or substitute in themselves. Only through the tragic climax can he - and the audience - find redemption.