Divisionism, also called chromoluminarism, was the characteristic style in Neo-Impressionist painting defined by the separation of colors into individual dots or patches which interacted optically.  
By requiring the viewer to combine the colors optically instead of physically mixing pigments, Divisionists believed they were achieving the maximum luminosity scientifically possible. Georges Seurat founded the style around 1884 as chromoluminarism, drawing from his understanding of the scientific theories of Michel Eugène Chevreul, Ogden Rood and Charles Blanc, among others. Divisionism developed along with another style, Pointillism, which is defined specifically by the use of dots of paint and does not necessarily focus on the separation of colors.  
|A Sunday Afternoon on the Island of La Grande Jatte|
|Medium||Oil on canvas|
|Dimensions||207.6 cm× 308 cm(81.7 in× 121.3 in)|
|Location||Art Institute of Chicago, Chicago|
|Portrait of Félix Fénéon|
|Medium||Oil on canvas|
|Dimensions||73.5 cm× 92.5 cm(28.9 in× 36.4 in)|
|Location||The Museum of Modern Art, New York|
|Self-Portrait with Felt Hat|
|Artist||Vincent van Gogh|
|Medium||Oil on canvas|
|Dimensions||44 cm× 37.5 cm(17.3 in× 14.8 in)|
|Location||Van Gogh Museum, Amsterdam|
|La danse, Bacchante|
|Medium||Oil on canvas|
|Dimensions||73 cm× 54 cm(28.7 in× 21.2 in)|
|Location||Rijksmuseum Kröller-Müller, Otterlo, Netherlands|
|L'homme à la tulipe (Portrait de Jean Metzinger)|
|Medium||Oil on canvas|
|Dimensions||72.4 cm× 48.5 cm(28.5 in× 19.1 in)|
Divisionism is the technique of painting separate dots or patches of different colors in close proximity, which interact optically in the viewer's perception to generate more luminous colors. The paints are not actually mixed but viewed close together, so the separate colors of light reflected by the paints mixes in the eye and brain; the process is called additive mixing  and is also used by computer monitors.  This is different from mixing different paints together to produce a new color by subtractive mixing  which is also how laser printers produce colors.  Despite the theory, Seurat's paintings don't actually use true additive mixture, since the colors reflected by his paints as he used them don't actually mix in the eye. Instead, Seurat used highly contrasting colors in close proximity, but not close enough to mix additively; this effect is called simultaneous contrast, which creates a mild shimmering appearance and slightly increases the colors' apparent visual intensity.  
Impressionism was a movement that originated in France in the 1870s, characterized by the use of short, broken brushstrokes to capture the effects of light and atmosphere in a scene, rather than creating highly detailed and accurate representations. The Impressionists sought to create an "impression" of a scene rather than a detailed and finished painting. Divisionism, also known as Pointillism, developed from Impressionism in the 1880s. The Divisionists used a technique of placing small, distinct dots of color next to one another on the canvas, rather than mixing the colors on the palette. This created a more vibrant and dynamic effect, but also required a higher level of skill and precision. Neo-Impressionism emerged in the late 19th century, used more precise and geometric shapes to build compositions, and was strongly influenced by the scientific study of color theory and optical color effects, to create a more harmonious and luminous painting.    
Scientists or artists whose theories of light or color had some impact on the development of Divisionism include Charles Henry, Charles Blanc, David Pierre Giottino Humbert de Superville, David Sutter, Michel Eugène Chevreul, Ogden Rood and Hermann von Helmholtz. 
Divisionism, along with the Neo-Impressionism movement as a whole, found its beginnings in Georges Seurat's masterpiece, A Sunday Afternoon on the Island of La Grande Jatte . Seurat had received classical training at the École des Beaux-Arts, and, as such, his initial works reflected the Barbizon style. In 1883, Seurat and some of his colleagues began exploring ways to express as much light as possible on the canvas  By 1884, with the exhibition of his first major work, Bathing at Asnières , as well as croquetons of the island of La Grande Jatte, his style began taking form with an awareness of Impressionism, but it was not until he finished La Grande Jatte in 1886 that he established his theory of chromoluminarism. In fact, La Grande Jatte was not initially painted in the Divisionist style, but he reworked the painting in the winter of 1885-86, enhancing its optical properties in accordance with his interpretation of scientific theories of color and light 
Charles Blanc's Grammaire des arts du dessin introduced Seurat to the theories of color and vision that would inspire chromoluminarism. Blanc's work, drawing from the theories of Michel Eugène Chevreul and Eugène Delacroix, stated that optical mixing would produce more vibrant and pure colors than the traditional process of mixing pigments.  Mixing pigments physically is a subtractive process with cyan, magenta, and yellow being the primary colors. On the other hand, if colored light is mixed together, an additive mixture results, a process in which the primary colors are red, green and blue.
In Divisionist color theory, artists interpreted the scientific literature through making light operate in one of the following contexts: 
Seurat's theories intrigued many of his contemporaries, as other artists seeking a reaction against Impressionism joined the Neo-Impressionist movement. Paul Signac, in particular, became one of the main proponents of divisionist theory, especially after Seurat's death in 1891. In fact, Signac's book, D’Eugène Delacroix au Néo-Impressionnisme, published in 1899, coined the term Divisionism and became widely recognized as the manifesto of Neo-Impressionism. 
In addition to Signac, other French artists, largely through associations in the Société des Artistes Indépendants, adopted some Divisionist techniques, including Camille and Lucien Pissarro, Albert Dubois-Pillet, Charles Angrand, Maximilien Luce, Henri-Edmond Cross and Hippolyte Petitjean.  Additionally, through Paul Signac's advocacy of Divisionism, an influence can be seen in some of the works of Vincent van Gogh, Henri Matisse, Jean Metzinger, Robert Delaunay and Pablo Picasso.  
In 1907 Metzinger and Delaunay were singled out by the critic Louis Vauxcelles as Divisionists who used large, mosaic-like 'cubes' to construct small but highly symbolic compositions.  Both artists had developed a new sub-style that had great significance shortly thereafter within the context of their Cubist works. Piet Mondrian, Jan Sluijters and Leo Gestel, in the Netherlands, developed a similar mosaic-like Divisionist technique circa 1909. The Futurists later (1909–1916) would adapt the style, in part influenced by Gino Severini's Parisian experience (from 1907), into their dynamic paintings and sculpture. 
The influence of Seurat and Signac on some Italian painters became evident in the First Triennale in 1891 in Milan. Spearheaded by Grubicy de Dragon, and codified later by Gaetano Previati in his Principi scientifici del divisionismo of 1906, a number of painters mainly in Northern Italy experimented to various degrees with these techniques.
Pellizza da Volpedo applied the technique to social (and political) subjects; in this he was joined by Morbelli and Longoni. Among Pellizza's Divisionist works were Speranze deluse (1894) and Il sole nascente (1904).  It was, however, in the subject of landscapes that divisionism found strong advocates, including Giovanni Segantini, Gaetano Previati, Angelo Morbelli and Matteo Olivero. Further adherents in painting genre subjects were Plinio Nomellini, Rubaldo Merello, Giuseppe Cominetti, Camillo Innocenti, Enrico Lionne, and Arturo Noci. Divisionism was also in important influence in the work of Futurists Gino Severini (Souvenirs de Voyage, 1911); Giacomo Balla (Arc Lamp, 1909);  Carlo Carrà (Leaving the scene, 1910); and Umberto Boccioni (The City Rises, 1910).   
Divisionism quickly received both negative and positive attention from art critics, who generally either embraced or condemned the incorporation of scientific theories in the Neo-Impressionist techniques. For example, Joris-Karl Huysmans spoke negatively of Seurat's paintings, saying "Strip his figures of the colored fleas that cover them, underneath there is nothing, no thought, no soul, nothing".  Leaders of Impressionism, such as Monet and Renoir, refused to exhibit with Seurat, and even Camille Pissarro, who initially supported Divisionism, later spoke negatively of the technique. 
While most divisionists did not receive much critical approval, some critics were loyal to the movement, including notably Félix Fénéon, Arsène Alexandre and Antoine de la Rochefoucauld. 
Although Divisionist artists strongly believed their style was founded in scientific principles, some people believe that there is evidence that Divisionists misinterpreted some basic elements of optical theory.  For example, one of these misconceptions can be seen in the general belief that the Divisionist method of painting allowed for greater luminosity than previous techniques. Additive luminosity is only applicable in the case of colored light, not juxtaposed pigments; in reality, the luminosity of two pigments next to each other is just the average of their individual luminosities.  Furthermore, it is not possible to create a color using optical mixture which could not also be created by physical mixture. Logical inconsistencies can also be found with the Divisionist exclusion of darker colors and their interpretation of simultaneous contrast. 
Throughout history, forms of art have gone through periodic abrupt changes called artistic revolutions. Movements have come to an end to be replaced by a new movement markedly different in striking ways.
Georges Pierre Seurat was a French post-Impressionist artist. He devised the painting techniques known as chromoluminarism and pointillism and used conté crayon for drawings on paper with a rough surface.
Pointillism is a technique of painting in which small, distinct dots of color are applied in patterns to form an image.
Paul Victor Jules Signac was a French Neo-Impressionist painter who, with Georges Seurat, helped develop the artistic technique Pointillism.
Henri-Edmond Cross, born Henri-Edmond-Joseph Delacroix, was a French painter and printmaker. He is most acclaimed as a master of Neo-Impressionism and he played an important role in shaping the second phase of that movement. He was a significant influence on Henri Matisse and many other artists. His work was instrumental in the development of Fauvism.
A Sunday Afternoon on the Island of La Grande Jatte was painted from 1884 to 1886 and is Georges Seurat's most famous work. A leading example of pointillist technique, executed on a large canvas, it is a founding work of the neo-impressionist movement. Seurat's composition includes a number of Parisians at a park on the banks of the River Seine. It is in the collection of the Art Institute of Chicago.
Orphism or Orphic Cubism, a term coined by the French poet Guillaume Apollinaire in 1912, was an offshoot of Cubism that focused on pure abstraction and bright colors, influenced by Fauvism, the theoretical writings of Paul Signac, Charles Henry and the dye chemist Michel Eugène Chevreul. This movement, perceived as key in the transition from Cubism to Abstract art, was pioneered by František Kupka, Robert Delaunay and Sonia Delaunay, who relaunched the use of color during the monochromatic phase of Cubism. The meaning of the term Orphism was elusive when it first appeared and remains to some extent vague.
Neo-Impressionism is a term coined by French art critic Félix Fénéon in 1886 to describe an art movement founded by Georges Seurat. Seurat's most renowned masterpiece, A Sunday Afternoon on the Island of La Grande Jatte, marked the beginning of this movement when it first made its appearance at an exhibition of the Société des Artistes Indépendants in Paris. Around this time, the peak of France's modern era emerged and many painters were in search of new methods. Followers of Neo-Impressionism, in particular, were drawn to modern urban scenes as well as landscapes and seashores. Science-based interpretation of lines and colors influenced Neo-Impressionists' characterization of their own contemporary art. The Pointillist and Divisionist techniques are often mentioned in this context, because they were the dominant techniques in the beginning of the Neo-impressionist movement.
Albert Dubois-Pillet was a French Neo-impressionist painter and a career army officer. He was instrumental in the founding of the Société des Artistes Indépendants, and was one of the first artists to embrace Pointillism.
Charles Angrand was a French artist who gained renown for his Neo-Impressionist paintings and drawings. He was an important member of the Parisian avant-garde art scene in the late 1880s and early 1890s.
Ogden Nicholas Rood was an American physicist best known for his work in color theory.
Asnières, now named Asnières-sur-Seine, is the subject and location of paintings that Vincent van Gogh made in 1887. The works, which include parks, restaurants, riverside settings and factories, mark a breakthrough in van Gogh's artistic development. In the Netherlands his work was shaped by great Dutch masters as well as Anton Mauve a Dutch realist painter who was a leading member of the Hague School and a significant early influence on his cousin-in-law van Gogh. In Paris van Gogh was exposed to and influenced by Impressionism, Symbolism, Pointillism, and Japanese woodblock print genres.
The Lagoon of Saint Mark, Venice is an oil on canvas painting by Paul Signac. This painting focuses on a seascape image which became a common theme late in Signac's life.
Baigneuses: Deux nus dans un paysage exotique is an oil painting created circa 1905 by the French artist and theorist Jean Metzinger (1883–1956). Two Nudes in an Exotic Landscape is a Proto-Cubist work executed in a highly personal Divisionist style during the height of the Fauve period. The painting is now in the Carmen Thyssen-Bornemisza Collection, Spain.
La danse is an oil painting created circa 1906 by the French artist and theorist Jean Metzinger (1883–1956). Bacchante is a pre-Cubist or Proto-Cubist work executed in a highly personal Divisionist style during the height of the Fauve period. Bacchante was painted in Paris at a time when Metzinger and Robert Delaunay painted portraits of one another, exhibiting together at the Salon d'Automne and the Berthe Weill gallery. Bacchante was exhibited in Paris during the spring of 1907 at the Salon des Indépendants, along with Coucher de soleil and four other works by Metzinger.
Coucher de soleil no. 1 is an oil painting created circa 1906 by the French artist and theorist Jean Metzinger (1883–1956). Coucher de soleil no. 1 is a work executed in a mosaic-like Divisionist style with a Fauve palette. The reverberating image of the sun in Metzinger's painting is an homage to the decomposition of spectral light at the core of Neo-Impressionist color theory.
Femme au Chapeau or Lucie au chapeau is an oil painting created circa 1906 by the French artist and theorist Jean Metzinger (1883–1956). The work is executed in a highly personal Divisionist style with a marked Proto-Cubist component during the height of Fauvism. Femme au Chapeau exhibits a presentiment of Metzinger's subsequent interest in the faceting of form associated with Cubism. The painting now forms part of the collection of the Korban Art Foundation.
Le Chahut is a Neo-Impressionist painting by Georges Seurat, dated 1889–90. It was first exhibited at the 1890 Salon de la Société des Artistes Indépendants in Paris. Chahut became a target of art critics, and was widely discussed among Symbolist critics.
Models, also known as The Three Models and Les Poseuses, is a work by Georges Seurat, painted between 1886 and 1888 and held by the Barnes Foundation in Philadelphia. Models was exhibited at the fourth Salon des Indépendants in spring of 1888.
Portrait of Irma Sèthe is an oil on canvas painting by the Belgian neo-impressionist painter Théo van Rysselberghe. The work is a portrait, painted in pointillist style, of Irma Sèthe, one of the heiress of a musical Brussels family close to the painter, playing the violin. The work is now in the private collection of the Musée du Petit Palais in Geneva.