Nineteenth-century aesthetic theory frequently makes the eye the preeminent means by which we perceive truth.

• In The Hero as Poet (1840), Thomas Carlyle writes, "Poetic creation, what is this but seeing the thing sufficiently? The word that will describe the thing follows of itself from such clear intense sight of the thing."
• In his definition of the pathetic fallacy (1856; NAEL 8, 2.1322), which to him characterizes bad poetry, John Ruskin differentiates "between the ordinary, proper, and true appearances of things to us; and the extraordinary, or false appearances, when we are under the influence of emotion."
• In The Function of Criticism at the Present Time (1865; NAEL 8, 2.1384–97), Matthew Arnold defines the ideal in all branches of knowledge as "to see the object as in itself it really is."

This emphasis in nineteenth-century aesthetic theory on seeing the object as it really is has a counterpart in the importance of illustrating literature, particularly novels. Dickens worked most frequently with two great illustrators, George Cruikshank and Phiz (the pseudonym of Hablot Knight Browne). William Makepeace Thackeray drew his own illustrations. In the works of these authors and others, the juxtaposition of text and picture creates a characteristic nineteenth-century style, which the critic Martin Meisel defines in his book Realizations as a union of pictorialism with narrative, creating richly detailed scenes that at once imply the stories that precede and follow and symbolize their meaning.

At the same time, developments in visual technology made it possible to see more and in new ways. Nineteenth century optical devices, creating illusions of various sorts, were invented near the beginning of the century: the thaumatrope, the phenakistoscope, the zoetrope, the stroboscope, the kaleidoscope, the diorama, and the stereoscope. Other inventions — such as the camera lucida, the graphic telescope, the binocular telescope, the binocular microscope, the stereopticon, and the kinetoscope — projected, recorded, or magnified images. Most important, the photographic camera provided an entirely new way of recording objects and people and transformed many areas of life and work.

The selections in this topic concentrate on one aspect of the Victorian visual imagination: the visual illustration of poetry through the accumulation of visual detail. In Mariana (NAEL 8, 2.1112–14), for example, Tennyson conveys Mariana's despair through the objects that surround her. In a review, Arthur Henry Hallam uses the term "picturesque" to describe Tennyson's first volume of poems. Contrasted with the descriptive, which gives an objective account of appearances, the picturesque presents objects through the medium of emotion. Such poetry lends itself to illustration, and nineteenth-century editions of poetry, such as Moxon's Illustrated Tennyson or Macmillan's 1862 edition of Christina Rossetti's Goblin Market and Other Poems, frequently contained illustrations, much as novels did.

Illustration's importance in nineteenth-century literary theory created a particularly close connection between painting and poetry. Dante Gabriel Rossetti painted portraits to illustrate his poems, such as The Blessed Damozel, and created pairs of poems and paintings such as Lilith, Sibylla Palmifera, and Astarte Syriaca. Poets also frequently took painting as the subject of their poetry, as in Robert Browning's Fra Lippo Lippi (NAEL 8, 2.1271–80) or Andrea del Sarto (NAEL 8, 2.1280–86). Similarly, a number of writers created prose descriptions of great paintings that were almost a kind of prose poetry, like John Ruskin's description of J. M. W. Turner's The Slave Ship (NAEL 8, 2.1321–22) or Walter Pater's description of Leonardo Da Vinci's La Gioconda (NAEL 8, 2.1510–11). Nineteenth-century artists felt a kinship between picture-making with words and picture-making with images that linked the sister arts of poetry and painting in close relationship.