In his essay The New Arts! or The Role of Chance in Artistic Creation, Strindberg described how he painted his work Underlandet:
“During quiet moments, I paint. In order to master the material, I choose a medium-sized canvas or preferably a panel, so that I can complete the painting in two or three hours, as long as my inspiration lasts. I am seized by whatever subject comes to mind. I picture a shadowy forest, and beyond the sun setting over the sea. [...] with the palette knife that I use for the purpose – I own no brushes! – I spread the paints over the panel, and there I blend them so that I have something approaching a depiction of the scene. The hole in the middle of the canvas represents the sea horizon; now the forest interior expands outwards, branches, treetops grouped into colours, fourteen, fifteen, random but always harmonious. The canvas is covered; I step back and look! Well I never! I cannot make out any sea. The illuminated hole shows an endless perspective of pink and blue-tinged light, where airy, incorporeal, unfathomable beings float about like fairies trailing clouds. The forest has become a dark, subterranean cavern choked by undergrowth: and the foreground – let us see what we have there – rocks covered in lichens that you will not find anywhere else – and there to the right the knife has slicked the paints too much, so that they are like reflections on water – look at that! It is a pond. Excellent! What now? Above the water there is a splash of white and pink whose origin and meaning I cannot explain. One moment! – a rose! – The knife works for two seconds and the pond is ringed with roses, so many roses! A light touch of the finger here and there blends together the intractable colours, they melt together and dispel the harsh shades, thin them out, dissolve them, and there is the painting! […] The art of the future (which will disappear like everything else!). Capturing the essence of nature; above all capturing nature’s creativity!”
Strindberg had no formal artistic training. He only painted landscapes, but never while directly looking at the subject. The paintings were executed during periods when, for various reasons, Strindberg suffered writer’s block. Today his paintings sell at auctions for record sums.