Essay on Poetic Theory

A Defence of Poetry (1821)

by Percy Bysshe Shelley


Percy Bysshe Shelley was born to a wealthy family in Sussex, England. He attended Eton and Oxford, where he was expelled for writing a pamphlet championing atheism. Shelley married twice before he drowned in a sailing accident in Italy at the age of 29. His first wife committed suicide, and shortly thereafter he married his second wife, Mary Wollstonecraft Shelley, who was the author of Frankenstein and the daughter of Mary Wollstonecraft, author of A Vindication of the Rights of Woman. Among Shelley’s closest friends were the other famous Romantic poets of the day, among them John Keats, whose death inspired Shelley’s “Adonais,” and Lord Byron.

Shelley’s “Defence of Poetry” is unusual compared with similarly titled “defenses” of poetry. Shelley’s essay contains no rules for poetry, or aesthetic judgments of his contemporaries. Instead, Shelley’s philosophical assumptions about poets and poetry can be read as a sort of primer for the Romantic movement in general. In this essay, written a year before his death, Shelley addresses “The Four Ages of Poetry,” a witty magazine piece by his friend, Thomas Love Peacock. Peacock’s work teases and jokes through its definitions and conclusions, specifically that the poetry has become valueless and redundant in an age of science and technology, and that intelligent people should give up their literary pursuits and put their intelligence to good use. Shelley takes this treatise and extends it, turning his essay into more of a rebuttal than a reply. To begin, Shelley turns to reason and imagination, defining reason as logical thought and imagination as perception, adding, “reason respects the differences, and imagination the similitudes of things.” From reason and imagination, man may recognize beauty, and it is through beauty that civilization comes. Language, Shelley contends, shows humanity’s impulse toward order and harmony, which leads to an appreciation of unity and beauty. Those in “excess” of language are the poets, whose task it is to impart the pleasures of their experience and observations into poems. Shelley argues, that civilization advances and thrives with the help of poetry. This assumption then, through Shelley’s own understanding, marks the poet as a prophet, not a man dispensing forecasts but a person who “participates in the eternal, the infinite, and the one.” He goes on to place poetry in the column of divine and organic process: “A poem is the very image of life expressed in its eternal truth . . . the creation of actions according to the unchangeable forms of human nature, as existing in the mind of the Creator.” The task of poets then is to interpret and present the poem; Shelley’s metaphor here explicates: “Poetry is a mirror which makes beautiful that which is distorted.”

The next portion of Shelley’s argument approaches the question of morality in poetry. To Shelley, poetry is utilitarian, as it brings civilization by “awaken[ing] and enlarg[ing] the mind itself by rendering it the receptacle of a thousand unapprehended combinations of thought. Poetry lifts the veil from the hidden beauty of the world.” Shelley also addresses drama and the critical history of poetry through the ages, beginning with the classical period, moving through the Christian era, and into the middle ages until he arrives back in his present day, pronouncing the worth of poets and poetry as “indeed divine,” and the significant role that poets play, concluding with his famous last line: “Poets are the unacknowledged legislators of the world.”

According to one mode of regarding those two classes of mental action, which are called reason and imagination, the former may be considered as mind contemplating the relations borne by one thought to another, however produced, and the latter, as mind acting upon those thoughts so as to color them with its own light, and composing from them, as from elements, other thoughts, each containing within itself the principle of its own integrity. The one is the το ποιειν, or the principle of synthesis, and has for its objects those forms which are common to universal nature and existence itself; the other is the το λογιςειν, or principle of analysis, and its action regards the relations of things simply as relations; considering thoughts, not in their integral unity, but as the algebraical representations which conduct to certain general results. Reason is the enumeration of qualities already known; imagination is the perception of the value of those qualities, both separately and as a whole. Reason respects the differences, and imagination the similitudes of things. Reason is to imagination as the instrument to the agent, as the body to the spirit, as the shadow to the substance.

Poetry, in a general sense, may be defined to be “the expression of the imagination”: and poetry is connate with the origin of man. Man is an instrument over which a series of external and internal impressions are driven, like the alternations of an ever-changing wind over an Æolian lyre, which move it by their motion to ever-changing melody. But there is a principle within the human being, and perhaps within all sentient beings, which acts otherwise than in the lyre, and produces not melody alone, but harmony, by an internal adjustment of the sounds or motions thus excited to the impressions which excite them. It is as if the lyre could accommodate its chords to the motions of that which strikes them, in a determined proportion of sound; even as the musician can accommodate his voice to the sound of the lyre. A child at play by itself will express its delight by its voice and motions; and every inflexion of tone and every gesture will bear exact relation to a corresponding antitype in the pleasurable impressions which awakened it; it will be the reflected image of that impression; and as the lyre trembles and sounds after the wind has died away; so the child seeks, by prolonging in its voice and motions the duration of the effect, to prolong also a consciousness of the cause. In relation to the objects which delight a child these expressions are what poetry is to higher objects. The savage (for the savage is to ages what the child is to years) expresses the emotions produced in him by surrounding objects in a similar manner; and language and gesture, together with plastic or pictorial imitation, become the image of the combined effect of those objects, and of his apprehension of them. Man in society, with all his passions and his pleasures, next becomes the object of the passions and pleasures of man; an additional class of emotions produces an augmented treasure of expressions; and language, gesture, and the imitative arts, become at once the representation and the medium, the pencil and the picture, the chisel and the statute, the chord and the harmony. The social sympathies, or those laws from which, as from its elements, society results, begin to develop themselves from the moment that two human beings coexist; the future is contained within the present, as the plant within the seed; and equality, diversity, unity, contrast, mutual dependence, become the principles alone capable of affording the motives according to which the will of a social being is determined to action, inasmuch as he is social; and constitute pleasure in sensation, virtue in sentiment, beauty in art, truth in reasoning, and love in the intercourse of kind. Hence men, even in the infancy of society, observe a certain order in their words and actions, distinct from that of the objects and the impressions represented by them, all expression being subject to the laws of that from which it proceeds. But let us dismiss those more general considerations which might involve an inquiry into the principles of society itself, and restrict our view to the manner in which the imagination is expressed upon its forms.

In the youth of the world, men dance and sing and imitate natural objects observing in these actions, as in all others, a certain rhythm or order. And, although all men observe a similar, they observe not the same order, in the motions of the dance, in the melody of the song, in the combinations of language, in the series of their imitations of natural objects. For there is a certain order or rhythm belonging to each of these classes of mimetic representation, from which the hearer and the spectator receive an intenser and purer pleasure than from any other: the sense of an approximation to this order has been called taste by modern writers. Every man in the infancy of art observes an order which approximates more or less closely to that from which this highest delight results: but the diversity is not sufficiently marked, as that its gradations should be sensible, except in those instances where the predominance of this faculty of approximation to the beautiful (for so we may be permitted to name the relation between this highest pleasure and its cause) is very great. Those in whom it exists in excess are poets, in the most universal sense of the word; and the pleasure resulting from the manner in which they express the influence of society or nature upon their own minds, communicates itself to others, and gathers a sort of reduplication from that community. Their language is vitally metaphorical; that is, it marks the before unapprehended relations of things and perpetuates their apprehension, until the words which represent them, become, through time, signs for portions or classes of thoughts instead of pictures of integral thoughts; and then if no new poets should arise to create afresh the associations which have been thus disorganized, language will be dead to all the nobler purposes of human intercourse. These similitudes or relations are finely said by Lord Bacon to be “the same footsteps of nature impressed upon the various subjects of the world” [“De Augment. Scient.,” cap. i, lib. iii—Shelley]—and he considers the faculty which perceives them as the store-house of axioms common to all knowledge. In the infancy of society every author is necessarily a poet, because language itself is poetry; and to be a poet is to apprehend the true and the beautiful, in a word, the good which exists in the relation, subsisting, first between existence and perception, and secondly between perception and expression. Every original language near to its source is in itself the chaos of a cyclic poem: the copiousness of lexicography and the distinctions of grammar are the works of a later age, and are merely the catalogue and the form of the creations of poetry.

Originally Published: October 13, 2009

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Audio Article
 Percy  Bysshe Shelley


The life and works of Percy Bysshe Shelley exemplify Romanticism in both its extremes of joyous ecstasy and brooding despair. The major themes are there in Shelley’s dramatic if short life and in his works, enigmatic, inspiring, and lasting: the restlessness and brooding, the rebellion against authority, the interchange with nature, the power of the visionary imagination and of poetry, the pursuit of ideal love, and the untamed . . .

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Originally appeared in Poetry magazine.

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