At the beginning of the 18th century, the Englishman Jonathan Richardson became the first person to develop a system of art criticism. In An Essay on the Whole Art of Criticism as It Relates to Painting and An Argument in Behalf of the Science of a Connoisseur (both 1719), he develops a practical system of critical evaluation that reminds one of Jeremy Bentham’s utilitarian calculus. Establishing a hierarchy of values from 1 to 20—“sublimity” being the peak of artistic perfection—that anyone could learn to use, he suggests that criticism is merely a matter of ratings.

In the mid-18th century Alexander Gottlieb Baumgarten created the discipline of aesthetics, giving it a place as a separate philosophical study, and in so doing, afforded new criteria for critical judgment. In his most important work, Aesthetica (1750–58), he sets forth the difference between a moral and exclusively aesthetic understanding of art, a way of thinking that can be regarded as the major difference between a traditional and modern approach to art making and art criticism. Later in the century, Immanuel Kant’s Critik der Urteilskraft (1790; “Critique of Judgment”) introduced the ideas of a disinterested judgment of taste, the purposiveness of artistic form, and the difference between the beautiful and sublime. These ideas remain influential to the present day, especially in the formalist criticism that would dominate the mid-20th century.

Parallel with these developments, art history also came into its own in the mid-18th century in the person of the German historian-critic Johann Winckelmann, who took full advantage of the new formal parameters allowed by aesthetics. Generally regarded as the first systematic art historian, he was by training an archaeologist with a deep knowledge of antiquity. In works such as Gedancken über die Nachahmung der griechischen wercke in der Mahlerey und Bildhauer-Kunst (1765; “Reflections on the Painting and Sculpture of the Greeks”) and Geschichte der Kunst des Alterthums (1764; “The History of Ancient Art”), Winckelmann idealized Greek art for its “noble simplicity and quiet grandeur,” and in the process he helped bring about the rise of Neoclassicism in the arts. More important for art history and art criticism, he established a model for art-historical development based on these ancient foundations. He espoused the idea of a period style, whereby a visual idea slowly but surely unfolded in an organic sequence of artistic events, growing from a seed to a sturdy plant, which flowered and then decayed. More particularly, an initial “antique” (or archaic) style matured into a sublime style, whose gains were consolidated and refined into a beautiful style, which eventually collapsed into a decadent, anticlimactic, academic style of imitation. Winckelmann thought this pattern repeated in antiquity and in modern painting. Whether or not Winckelmann forced the parallel throughout history is beside the point; his idea of a discernible formal trajectory took hold.

But, just as some critics in the 17th century sought to expose the lawless alternatives to standing artistic models, Richardson’s and Winckelmann’s enlightened efforts to put art criticism on an objective basis were opposed by another Enlightenment figure, the great French encyclopaedist, author, and wit Denis Diderot. Aware of the increasingly “romantic,” unruly, informal—seemingly methodless—character of art, Diderot was concerned with its moral message (as his comments noting “the depravation of morals” in François Boucher’s painting reveal). He perceived that art seemed to have fewer and fewer clear—let alone absolute and rational—rules, which implied that it could be evaluated in a more personal, even irrational, altogether idiosyncratic way. The looser the rules, the more relative the standards by which art could be judged. He saw that the new freedom of art allowed for a new freedom of criticism. In a sense, unconventional art needed an unconventional criticism to give it a raison d’être.

Diderot reviewed Salons from 1759 to 1781. He wrote a book-length examination of the Salon of 1767, in which he not only assesses contemporary art but attempts to clarify its principles; building upon de Piles’s merging of emotion and intellect, he shows that philosophical evaluation and empirical documentation are inseparable in art criticism. The pages Diderot devotes to seven landscape paintings by Horace Vernet are particularly exemplary of his approach. Diderot describes Vernet’s landscapes with great precision, as though he were walking through them; the peripatetic response to the topical is basic to art criticism, which deals with new art whose value has not yet been clearly established. In addition to inspiring such a literal mode of interpretation, these landscapes also stimulated Diderot’s intellect and evoked a certain mood. Diderot praises Vernet because his landscapes appealed to his mind as well as his emotions—because spontaneous attunement to them led to reflection. This double demand—that the critic be responsive to the spirit of a work of art so that he is able to find the truth in it or, to put this another way, that he appreciate it in its immediacy so that he can find the meanings it mediates—has been the credentials of the critic ever since. The critic must have feelings as well as knowledge, so that, like Diderot at his best, his criticism fuses “colorful description and arresting philosophical observations,” as the American scholar Jean Eldred writes.

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aesthetics: Taste, criticism, and judgment

In the 18th century it also became apparent that, if successful, criticism just might elevate a subjective preference into a canonical art. Artists have always been threatened by destructive criticism—major 18th-century artists, such as Boucher, Quentin de la Tour, and Jean-Baptiste Greuze, did not exhibit in 1767 out of fear of it. But constructive criticism, showing how emotionally rich and intellectually meaningful his art was, could give an artist immortality. Thus, if the critic could make a convincing case for an art, on whatever “theoretical” ground, as Diderot did for Vernet, then it gained a certain significance that, however eccentric, gave it credibility, even fame, at least for a short time.