MADRID — In art as in life, the word sketch is complicated. A sketch of an unknown city might be useful as a map, especially if accompanied by advice on how to avoid the sketchy places. Sketches tend to be valued less than a finished work, except when they seem to capture something uniquely spontaneous and emotionally direct. At several moments in the history of art, in 16th-century Venice and again in the early 19th century, “sketchiness” became a virtue, a style in itself, and a reaction to the established way of finishing off a painting with a public, polished sheen.
A new exhibition at the Museo del Prado has gathered more than 70 oil sketches by Peter Paul Rubens, who played a key role in the evolution of the form from a preparatory tool to something far more intriguing and ambiguous: small but self-sufficient paintings with color on durable supports, with enough finish and substance that they often have a life of their own. Rubens made almost 500 of these oil sketches, and they were prized by connoisseurs and collectors even during the artist’s lifetime. Many were made as part of the process of developing a painting; others were probably made to sell an idea to a client; yet others were made to guide Rubens’s assistants and collaborators in the production of a finished work. In this country, people who mainly frequent smaller museums may be more familiar with his sketches than his finished work.
In the 1760s, the French philosopher Denis Diderot asked: “Why does a beautiful sketch accord greater pleasure than a beautiful painting?” and he answered with a distinctly modern sensibility: “Perhaps the sketch attracts us so strongly because being somewhat indeterminate it leaves more to our imagination, which sees in it anything it pleases.” Sketches thus empower the viewer.
This makes perfect sense when Rubens’s sketches are seen in the context of the Prado, which holds the world’s most extensive collection of the artist’s work. Rubens served as a diplomat to the Spanish crown. He lived and worked in what is now Belgium, then a region governed by the Spanish royal family, and he was the most revered painter of his age, regularly commissioned by the Spanish Habsburg rulers, especially Philip IV, who demanded dozens of works, many of them on a massive scale.
Walk the corridors of this museum, and the work of Rubens is so overwhelming in its rhetorical impact that for all of its many delights it can also feel oppressive. The central gallery of the museum’s 18th-century Villanueva building is dominated by Rubens, whose mastery of mythological and biblical arcana makes him seem the smartest boy in the room.
Given the scale of this space, Rubens’s control over the architecture of images — the larger argument that results from geometry, massing, color and the sense of motion — makes his work particularly effective. His portrait of the Duke of Lerma on horseback, which had enormous influence on later portraitists, radiates infectious confidence and a celestial, blue-sky endorsement of pure power. It is so convincing that one is inclined to forget what a miserable, reactionary figure the subject was, including his key role in the expulsion of the Moriscos, Christian converts from Muslim backgrounds, who were an easy target for nativist demagoguery.
Compared with the “finished” works in this gallery, the sketches are intimate, engaging and often full of a humor that gets airbrushed out of the larger, more formal works. Unlike musical sketches, in which the composer progressively adds in details of inner lines and orchestration, the best of the oil sketches don’t feel like way stations on the road to completion. In some cases, for example the sketches made for a prominent Jesuit church in Antwerp that was mostly destroyed by a lightning strike and fire in 1718, the preparatory works survive while the finished ones were lost. Sketches also exist for work that was never finished, or lost. But even for works that were finished, the sketches often stand apart, not so much first thoughts or discarded inclinations, but simply a different view of the matter.
In several juxtapositions of sketch to finished work, one notes differences without necessarily acknowledging improvement. A large, horizontal canvas, “The Recognition of Philopoemen,” was sketched by Rubens and then finished by both Rubens and Frans Snyders, who was tasked with the morbidly excessive kitchen still life that occupies much of this curious depiction of a Greek general who was so modest he helped cook a banquet in his own honor. In Rubens’s sketch, the animal carcasses and vegetal matter seem to swirl on the table in a lurid dream of gluttony. In the final version, this has been remade as a rather static study in textures and surfaces, so that the sketch relates to the finished painting rather like a real plate of food relates to the picture of food one finds in a glossy recipe magazine.
Two other juxtapositions, both devoted to the same subject, suggest how Rubens operated like a contemporary stage director rethinking classic works. Each iteration of the drama goes in a slightly different direction, teasing out diverse elements. Multiple efforts to depict the discovery of Achilles among the daughters of Lycomedes are included, and taken together they suggest four different vectors of imagination, not a single process of refining.
The subject, from a Roman epic poem, is obscure to modern readers: To save her son from death in war, Achilles’s mother, Thetis, hides him in female attire, but his cover is blown when the wily Odysseus and Diomedes place weapons within his reach, which he reflexively brandishes. In one sketch, Achilles looks like an awkward boy in a dress; in another, he is an androgynous but warlike figure, reminiscent of the biblical hero Judith; in a third, he comically tries on a war helmet, as if in fashion show; and in a fourth, the same helmet episode becomes more serious and menacing, the figure more clearly masculine in a traditional sense. One could play this episode for laughs, or take it seriously as a commentary on the complicated sexual impulses of Greek heroes; Rubens is capable of both.
The meaning of a sketch today is colored by our own relationship to rhetoric and public life. Rhetoric, once understood as the art of persuasion, is now almost synonymous with insincerity and hype; and opinion, once seen as hollow and groundless when compared with true knowledge, is now the dominant means of discourse. Sketches, if seen as less “rhetorical,” may read as more truthful. But in an age of half-finished thoughts and impromptu stabs at argument, there is something to be said for finishing a work, drawing out its full meaning and giving it the care of finality and conclusion. Do we credit Rubens as a master orator who take pains to make his public works convincing, or as a poet of stirrings and intimations who came closest to authenticity in his sketches?
Very likely, we will tend to Diderot’s sense that sketches are better than finished works because they empower us, the viewer, to complete them. But there’s no understanding Rubens’s grand canvases made without placing oneself in a far more uncomfortable position: If you don’t surrender to them, at least for a moment, you haven’t been looking closely enough.
Rubens: Painter of Sketches is on view at the Museo Nacional del Prado through Aug. 5. For more information, visit museodelprado.es.