The concept of visual and mental image defined by Sérusier in A B C of painting was taken up by J.D. The naturalistic image received by the painter is metamorphosed on the canvas : in the first place, the process begins by a simplification, because of the reproduction on the twodimension plane surface of the painting.  In addition to the reduction of the " primitive visual image " we must also consider the modifications due to memory, personal feelings (of beauty, ugliness, harmony) psychological and physiological states of every human being, which vary by definition (i. e " sensitivity ").  All these factors, of unequal importance, condition the primitive image and change it into a " mental one ", worked out by the artist at work.