It was believed that Van Gogh suffered from syphilis and this led to a condition later in life with his eyesight as well as affecting his mental state. It was said that he started to see things with a yellow halo around the objects, which is one reason why his later painting like Starry Night have emphasis on "hazy" patterns.
In Provence: Vincent van Gogh spent nearly two years in Provence and it is during this time that many believe him to have painted his best works. Again, it's impossible to easily categorize his paintings during his time in Arles and Saint-Rémy. Suffice it to say that this two year period in his life yielded what can arguably be called the most brilliant paintings he would ever produce. There are so many different specific works which warrant more study than I could ever begin to undertake: his outstanding portraits of the Roulin family, his works in Arles (the famous The Café Terrace on the Place du Forum or The Night Café in the Place Lamartine) or the surrounding countryside (his many churning cypresses trees and olive groves, for example), as well as what some consider to be his one greatest work of all, Starry Night at right above. It's fascinating to understand that even as Vincent's artistic brilliance climbed to new heights in Provence, so too did his physical and particularly his mental state make similar, radical advances (for the worse).
