In the second half on the nineteenth century a new school in painting appeared in Paris rejecting the old rigid structures. Impressionism, as its name indicates, focuses more on the fleeting feelings a scene evoques in the painter creating a dream-like artwork in which boundaries between elements in a picture are quite blurred. So, it is a movement that does not seek to replicate or re-present nature, but to exteriorise the impressions it left in the mind.
In literature, Impressionism is usually a technique that we find in short stories that deal with fewer characters. The compact size of this genre allows the writer to focus much more on the feelings and state of mind of his characters, rather than trying to establish some sort of a literary reality.
In short stories by Pope, James, Twain and others, we usually come across a character who reflects on events, who is disturbed by them and seems to have been deeply obsessed by them. We see a mind thinking, dreaming, fantacising about details that are not necessarily true. Impressionism gave room to psychological narration of passions, fears, dellusion and madness.