PHILADELPHIA — In the space of three small galleries in the Barnes Collection exhibition “Suzanne Valadon: Model, Painter, Rebel,” you encounter one of the most exciting transformations in art history.

Valadon, born as Marie-Clémentine Valadon in 1865, is seen first as the subject of paintings by other artists, including as a voluptuous siren, floating in a stormy sea, with blond hair flowing in the water and arms outstretched to ensnare a hapless mariner. Next, we see her early work, domestic sketches of her son and mother, evocative but sometimes a little clumsy. And then we turn the corner, and there she is, fully fledged, a brilliant artist, making breathtaking paintings that have the flat, colorful solidity of Gauguin, but a piercing intelligence and emotional insight.

She was self-taught, and in the span of just a little more than a decade, went from competence to mastery, and not just mastery. She uncovered and made legible new kinds of domesticity beyond the expectations of bourgeois propriety. She was to interior space what painters of the sublime were to the natural world, an explorer and an adventurer, charting new realms of ambition, desire and ennui.

Valadon came to the bohemian world of French art through the servant’s entrance, working first as an artist’s model. Respectable women didn’t do this. The work required professionalism and stamina, the ability to hold a pose, to erase one’s particularity, to suppress or exaggerate emotions, and to defend one’s ego and body against male painters who would exploit both. These skills were too often rewarded with sexual harassment and abuse. Women were idealized in paint but dehumanized in person.

Valadon was only 15 when she began to model, posing for artists including Gustav Wertheimer, who painted the image of her as a siren when she was about 17. She also appears in works by Toulouse-Lautrec, Pierre Puvis de Chavannes and Renoir, who used her in two of his better paintings, “Dance at Bougival” and “Dance in the City.” When she was 18, she bore a child (the father remains unknown), who grew up to be the painter Maurice Utrillo, a troubled figure who was not nearly as inventive as his mother. And she had affairs with the composer Erik Satie and Toulouse-Lautrec, who gave her the nickname Suzanne, based on the biblical Susanna, ogled and abused by the Elders in a story from the Book of Daniel.

Standard accounts of Valadon’s life suggest she used her time modeling to absorb artistic wisdom from the male painters who objectified her. Maybe, though it’s hard to imagine how much practical information she could glean while sitting on the opposite side of the easel. Her early drawings suggest, rather, an extraordinary amount of raw talent, followed by prodigiously rapid development. She stopped modeling in 1906 and by 1912 was painting at a very high level. Between her first artistic forays and a large 1912 group portrait of her with her family — including her son Maurice, her son’s friend André Utter and her mother — she married, divorced and built a self-sufficient career as an independent artist.

The painting, titled “Family Portrait,” is a stunner. Utter, her lover who was then in his mid-20s, is seen mostly in profile. Her son, who suffered from alcoholism, droops dejectedly in the foreground, and her mother looks in from behind, age scarring her face like water scours canyons. Valadon is the center of the grouping, her hand on her heart, her eyes directly addressing the viewer. The gesture with her right hand has the self-deprecating confidence of a someone who is almost terrified of her own abilities. She is the head of the family, the author of the image, a beautiful woman with a lover (and later husband) almost half her age. She has forged a family unlike almost any other family one might see in a painting from the 19th or 20th centuries.

Mary Cassatt or Berthe Morisot would never have painted anything like this. They not only came from an earlier generation, but they also came from money and privilege. Nor were they likely to paint their younger lover entirely naked, as Valadon did in her 1909 “Adam and Eve,” a double portrait in which Utter tenderly directs Valadon’s hand up to the fatal apple. As artist Lisa Brice speculates in a catalogue essay, “Valadon benefited from a level of freedom that Cassatt’s and Morisot’s upper-class standing made practically impossible for them to experience.”

This exhibition, billed as the first devoted to Valadon at a major U.S. museum, includes more than 50 works, and almost all of them are arresting. As suggested by the show’s subtitle (“Model, Painter, Rebel”) there is an effort to connect Valadon’s early years as subject to her greater career as maker. Is this seen in the particularly direct way that models look out of the canvas? In greater empathy for the naked female figure? In the way that, as Brice suggests, her portraits of other people are “always, to a degree, a self-portrait”?

Probably all of the above. But it’s also true that bodies, in her imagery, are thoroughly de-romanticized. Wertheimer, an Austrian painter who once had a significant international reputation, may have painted the young Valadon as a supple siren. But when Valadon paints bodies, they always seem to be stubbornly present. Not ugly, nor intentionally stolid, nor contorted into awkward shapes, as her friend Degas often painted them. But with their heavy outlines, and the riot of color and pattern that surround them, they inhabit the image with a forceful, blunt, plain-spoken insistence.

The last thing the woman in the 1923 work “The Blue Room,” often cited as Valadon’s masterpiece, is going to do is change her posture or her expression or her clothes. The world gathers around her and surges up to her formidable presence, and she remains, for as long as we look, immutable.

Throughout the show, you see how well Valadon knew the work of other artists. Gauguin and van Gogh and Cézanne are all somewhere in the background. But the pure weirdness of Valadon’s vision, the way a foot seems to summon a carpet to life, or a still life bubbles over into quasi-abstraction, erases any sense of indebtedness to others. Like the bodies she paints, her peculiarities are stubbornly present, convincing, insistent and irreducible.

Suzanne Valadon: Model, Painter, Rebel is on view at the Barnes Collection in Philadelphia through Jan. 9. For more information, visit barnesfoundation.org.