But the most usual species of connections among the different events which enter into any narrative composition is that of cause and effect; while the historian traces the series of actions according to their natural order, remounts to their secret springs and principles, and delineates their most remote consequences. He chooses for his subject a certain portion of that great chain of events which compose the history of mankind: Each link in this chain he endeavours to touch in his narration; sometimes unavoidable ignorance renders all his attempts fruitless; sometimes he supplies by conjecture what is wanting in knowledge; and always he is sensible that the more unbroken the chain is which he presents to his readers, the more perfect is his production. He sees that the knowledge of causes is not only the most satisfactory, this relation or connection being the strongest of all others, but also the most instructive;since it is by this knowledge alone we are enabled to control events and govern futurity.
Here, therefore, we may attain some notion of that of
about which all critics after Aristotle have talked so much, perhaps to little purpose, which they directed not their taste or sentiment by the accuracy of philosophy. It appears that in all productions, as well as in the epic and tragic, there is a certain unity required, and that on no occasion our thoughts can be allowed to run at adventures if we would produce a work that will give any lasting entertainment to mankind. It appears, also, that even a biographer who should write the life of Achilles would connect the events by showing their mutual dependence and relation, as much as a poet who should make the anger of that hero the subject of his narration.[10] Not only in any limited portion of life a man's actions have a dependence on each other, but also curing the whole period of his duration from the cradle to the grave; nor is it possible to strike off one link, however minute, in this regular chain without affecting the whole series of events which follow. The unity of action, therefore, which is to be found in biography or history differs from that of epic poetry, not in kind, but in degree. In epic poetry, the connection among the events is more close and sensible; the narration is not carried on through such a length of time; and the actors hasten to some remarkable period which satisfies the curiosity of the reader. this conduct of the epic poet depends on that particular situation of the imagination and of the passions which is supposed in that production. The imagination both of writer and reader is more enlivened, and the passions more inflamed than in history, biography, or any species of narration that confine themselves to strict truth and reality. Let us consider the effect of these two circumstances of an enlivened imagination and inflamed passions which belong to poetry, especially the epic kind, above any other species of composition; and let us see for what reason they require a stricter and closer unity in the fable.
, all poetry, being a species of painting, approaches us nearer to the objects than any other species of narration, throws a stronger light upon them, and delineates more distinctly those minute circumstances which, though to the historian they seem superfluous, serve mightily to enliven the imagery and gratify the fancy. If it be not necessary, as in the , to inform us each time the hero buckles his shoes and ties his garters, it will be requisite, perhaps, to enter into a greater detail than in the , where the events are run over with such rapidity that we scarce have leisure to become acquainted with the scene or action. Were a poet, therefore, to comprehend in his subject any great compass of time or series of events, and trace up the death of Hector to its remote causes in the rape of Helen or the judgment of Paris, he must draw out his poem to an immeasurable length in order to fill this large canvass with just painting and imagery.
The reader's imagination, inflamed with such a series of poetical descriptions, and his passions, agitated by a continual sympathy with the actors, must flag long before the period of narration and must sink into lassitude and disgust from the repeated violence of the same movements.
, that an epic poet must not trace the causes to any great distance will further appear if we consider another reason, which is drawn from a property of the passions still more remarkable and singular. It is evident that in a just composition all the affections excited by the different events described and represented add mutual force to each other; and that, while the heroes are all engaged in one common scene, and each action is strongly connected with the whole, the concern is continually awake, and the passions make an easy transition from one object to another.
