According to Aristotle tragedy is the representation of action and action consists of incidents and events. Plot is the arrangement of these incidents and events. It is better for the poet to choose a traditional story and then proceed to make out of it his own plot. Stories taken from history, mythology or legend are to be preferred, for they are familiar and easy to understand and they serve as guide-lines for characterisation. Having chosen his story or having invented it, the artist must subject it to a process of artistic selection and ordering. Only relevant incidents and situations are to be selected and they are to be so arranged that they seem to follow each other necessarily and inevitably. Moreover, the incidents chosen must be serious that is to say weighty of some importance, and not trivial, because tragedy is an imitation of a serious action having certain magnitude.
The tragic plot must be a whole, complete in itself; it should have a beginning, a middle and an end. There might be earlier parts of the story the antecedents and that may be communicated by the dramatist in due course. But the beginning must be clear and intelligible even without them. It must not provoke us to ask why and how. A middle is something that is consequent upon a situation that has gone before and which is followed by the catastrophe. The middle is everything between the first incident and the last. The middle is followed by the end. An end is that which is consequent upon a given situation but which is not followed by any further incident or situation. The middle must follow naturally and inevitably upon the beginning and must logically lead to the end or the catastrophe. Thus artistic wholeness implies logical link-up of the various incidents, events and situations that form the plot.
As regards 'magnitude' the plot must have a certain length or size. It should be neither too small nor-too large. According to O.B. Hardison magnitude implies that the plot must have order, logic, symmetry and perspicuity. The plot should be long enough to allow the process of change from happiness to misery initiated by 'the beginning' to be properly and completely developed, but not too long-for memory to encounter it as a whole. If it is too long the beginning would be forgotten before the end. If it is too small its different parts will not be clearly distinguishable from each other as in the casetrf living organism. Within these limits, the plot should be as large as possible.
The plot may have variety but it should have a unity. This unity arises from the fact that every event has a logical connection with the rest of the action and none of them is irrelevant. There might be episodes but the same must be properly integrated with the main action. Otherwise the episodic plots are the worst of all. The unity of plot does not consist in the unity of the hero, it consists in the unity of action. The plot should be an organic whole so that if one of its parts is displaced or removed the whole should be disjointed and disturbed.
A defective plot is that in which the rules of probability or necessity are not observed. The best tragic effect of pity and terror can be produced only if the plot contains elements of surprise and accident. But there should be a sort of 'inevitability' in the events.
The above discussion makes it clear that Aristotle emphasises the Unity of Action but has little to say about the Unity of Time and the Unity of Place. About the Unity of Time he merely says that tragedy should confine itself as far as possible to single revolution of the sun. No law is implied here. About the Unity of Place, Aristotle only mentioned once when comparing the epic and the tragedy that epic can narrate a number of actions going on simultaneously in different parts while in a drama such simultaneous actions cannot be represented for the stage is one part (place) and not several parts or places. In this respect too Aristotle was very much misunderstood by the renaissance and the French critics who deduced from his statement the rigid unity of place.
Plots are of two types, Simple and Complex. A Complex plot implies reversal of intention or situation and recognition. Reversal of situation is a change by which the action veers round to its opposite. Recognition is a change from ignorance to knowledge. Both these parts of the plot turn upon surprise. A third part of the plot is the tragic incident such as death. Hamartia, Perepeteia, and Anagnorisis
In Aristotle's conception, "Hamartia, Perepeteia and Anagnorisis all hang together in the ideal schematisation of the tragic plot." Hamartia is the tragic error and it is related to the character of the hero but in a successful plot it is so closely worked into the plot as to be inseparable from it. The miscalculation of the hero causes a chain of incidents which result in the change from good fortune to bad which the tragic plot depicts. Both Perepeteia and Anagnorisis are incidents, and parts of the plot.
The Perepetia is the fatal working of the plot to result the opposite of that intended. For example events do not turn up according to the intentions of expectations of the hero. They move in an opposite direction to his intention.
The Anagnorisis is the recognition of truth; it is the change from ignorance to knowledge. For example, Oedipus's knowledge of his parent that motivates him to some action and determines the direction of the action in the story. Recognition and reversal can be caused by separate incidents often however it is difficult to separate them. Besides the complex and simple plots there are also spectacular plots. This type of plot depends on incidents of suffering. Aristotle rates it very low. It is the plot which derives its effect from the depiction of torture, murder, maiming, violence, death etc. According to Aristotle, the tragic effect must be created naturally and not with artificial and theatrical aids. Such spectacular plots indicate a deficiency in the plot.
The unravelling of the plot should be done naturally and logically and not by the use of arbitrary devices like chance, supernatural intervention etc. "Gods should intervene only where it becomes necessary to explain the past, or announce future events external to the action." (Atkins) Aristotle does not consider Poetic Justice as necessary for Tragedy. Similarly there is happiness for some of the characters and misery for others. Such a double ending weakness the tragic effect and hence must be avoided. It is more proper to Comedy. Thus Aristotle is against the mixture of the tragic and the comic or Tragicomedy.
POINTS TO REMEMBER
1. Plot is the principal part of tragedy; it consists of events and incidents. The plot may be borrowed or invented by the poet.
2. Stories taken from history, mythology or legend are to be preferred.
3. There should be an artistic selection and ordering of events by the artist.
4. The incidents chosen should be serious and not trivial.
5. The tragic plot must have a certain magnitude, i.e., size—should have a middle and an end.
6. The plot must have a unity. It may have a variety but it should be a perfect whole.
7. A good plot must observe the rules of probability and should be able to surprise.
8. Plots may be simple or complex.
9. Hamartia is the tragic plan in the character of the hero and is inseparable from the plot.
10. The perepeteia is the fatal working of the plot to result the opposite of that intended.
11. The Anagnorisis is the recognition of truth—the change from ignorance to knowledge.
12. The plot should be developed naturally and logically, and not by the arbitrary devices such as chance, supernatural intervention, etc.
13. Poetic justice, though not necessary, may be maintained.
14. There should be no mixing of the tragic and the comic.