In Butterflies (Van Gogh series), how is the Butterflies as a subject discussed?
Butterflies are found in art and literature, often as symbols of freedom, transformation and life. Van Gogh used butterflies in his works as a symbol of hope.One of his favorite metaphors was about transformative possibilities.  In a letter to his sister Wil, Van Gogh says that like a grub eats salad roots, unknowing of the transformation that will take it to a beetle, we are not aware of our potential for metamorphosis.  Similarly, he as a "painter ought to paint pictures; possibly something else will come after that." Of prostitutes, such as those he met at brothels, Van Gogh wondered of any woman who fell into a life of degradation: "She is seeking, seeking, seeking -- does she herself know what?  Might she be transformed one day like a grub into a butterfly?"  That hope may have been on Van Gogh's mind when he took in pregnant Sien Hoornik, a prostitute, and her daughter when he lived in The Hague in 1882.In a letter to his friend Émile Bernard, Van Gogh uses the miracle of transformation from caterpillar to butterfly to consider what possibilities may be available in the universe:
"However, since nothing confutes the assumption that lines and forms and colours exist on innumerable other planets and suns as well, we are at liberty to feel fairly serene about the possibilities of painting in a better and different existence, an existence altered by a phenomenon that is perhaps no more ingenious and no more surprising than the transformation of a caterpillar into a butterfly or of a grub into a maybug. The existence of a painter-butterfly would be played out on the countless celestial bodies which, after death, should be no more inaccessible to us than the black dots on maps that symbolize towns and villages are in our earthly lives."When in need of solace, nature is where Van Gogh went to find peace.  In a letter to his sister Wilhelmina he writes that he finds to calm down it is best to "look at a blade of grass, the branch of a fir tree, an ear of wheat. So if you want to do, as the artists do, go look at the red and white poppies with their bluish leaves, their buds soaring on gracefully bent stems."
Sien Hoornik Émile Bernard Butterflies butterfly butterflies metamorphosis