I began to understand my sensations, to know what I wanted, at around the age of forty.. ..but only vaguely. At fifty, that is in 1880, I formulated … - Camille Pissarro

Each one of us [artists] has several facets. The surface often appears more important than what is inside, hence the errors of those who judge carelessly. How many times has that not happened to me! The surface is often complete in some people from the very beginning, but not the possession of their own sensations. From this come errors. Some natures achieve the surface very slowly j this is the least danger an artist runs. So one should not think of the surface or the appearance, but concentrate on what is inner!

The ones [compliments] I value most came from Edgar Degas who said he was happy to see my work becoming more and more pure. The etcher Bracquemond, a pupil of Ingres, said - possibly he meant what he said - that my work shows increasing strength. I will calmly tread the path I have taken, and try to do my best. At bottom, I have only a vague sense of its rightness or wrongness. I am much disturbed by my unpolished and rough execution. I should like to develop a smoother technique which, while retaining the old fierceness, would be rid of those jarring notes which make it difficult to see my canvases clearly except when the light falls in front. There lies the difficulty - not to speak of drawing.

This morning I received a letter from . He writes that he does not believe scientific research into the nature of color and light can help the artist, neither can anatomy nor the laws of optics. He wants to discuss these questions with me and find out my views. Now everything depends on how this knowledge is to be used. But surely it is clear that we could not pursue our studies of light with much assurance if we did not have as a guide the discoveries of Chevreul and other scientists. I would not have distinguished between local color and light if science had not given us the hint; the same holds true for complementary colors, contrasting colors, etc. 'Yes', he will tell me: 'but these have always been taken into account, look at Monet' It is at this point that the question becomes serious!