Updated: May 10
The paintings of that diverse group of artists that make up the impressionist and post-impressionist movements are so widely viewed today. It is easy to forget how controversial they were when they first appeared.
The term impressionism was coined by a French Journalist in 1875, who used it to ridicule a painting by Claude Monet Impression Sunrise which he said resembled wallpaper.
Another early critic faulted the impressionists' practice of painting with short, choppy, brush strokes. He accused them of firing paint at the canvas with a pistol.
And practically everyone thought the pictures were ugly, sometimes even shocking. Le Dejeuner Sur L'Herbe by the great impressionist precursor Edouard Manet was one of them. This painting depicting two women and two men picnicking in a woods scandalised Paris when it was first exhibited in 1863.
To the 19th century eyes, this new french art was an insult.
Like many art movements, impressionism was a reaction, in this case to the academic tradition of 19th century France. The realists decreed that art meant subjects were drawn from history or ancient mythology and painted on a vast scale.
Like the person who does not know anything about art, but knows what they like, these 19th-century art fans appreciated what they knew. And what they enjoyed were idyllic depictions of nymphs and naiads and vast narratives of past events.
But the impressionists, and later the post-impressionists, painted scenes from contemporary life, filled with everyday people engaged in everyday activities, taking place in familiar landscapes and on city streets.
In Manet's Le Dejeuner, for example, the artist has painted a scene from contemporary bohemian life in a way that parodies the conventions of the then-accepted academic art. The models were real people: Victorine Meurent, a professional model; either Gustave or Eugene Manet, brothers of the painter; and Ferdinand Leenoff, a Dutch sculptor. But they were placed in a scene that alluded to Renaissance composition and mythology. This rejection was evident in the piece, and the artist rejected such academic notions of art.
The avant-garde artists not only tackled contemporary subjects, but they also painted them differently.
Discoveries and innovations in colour theory and the invention of chemical pigments made the artist more aware of colours. They provided them with new colours to work with. This enabled them to reject the traditional use of continuous blended brush strokes. Consequently, they applied bright, high key colours in loose brush strokes, which were to be combined by the viewer's eye.
Thus the impressionists became less concerned with depicting the world as they saw it and more interested in recording their visual sensations of colour movement and light. There was a great deal of interest in painting fleeting scenes, on the spot, out of doors, which enabled them to capture spontaneous impressions of atmosphere and light.
Impressionism dates from the first impressionist exhibition in 1874 through the eighth in 1886 when the impressionists were acknowledged as serious artists by critics and general society.
Although post-impressionist wasn't coined until the 20th century, it came to apply roughly to the period of 1885-1905 and to include a group of painters whose different styles were linked only in their debt to and dissatisfaction with impressionism.
Artists like Paul Cezanne, Georges Seurat, Vincent Van Gogh and Paul Gaughin, all of whom had at first accepted impressionism, began to feel that the movement was rejecting too many of the traditional elements of picture-making in its quest for momentary sensations of light and colour.
So, while retaining the impressionists' bright palette, they began to explore form and expressiveness in painting and the modern notion of a picture as a beautiful area in its own right rather than a mirror of nature.
Of course, impressionism and post-impressionism are just terms relating to nineteenth artistic discoveries that shaped the course of twentieth-century art. The important thing is to look at the pictures and enjoy these achievements of intellect and sensation, colour and form, of genius and imagination.