Naïve art is a form of visual art that is created by a person who lacks the formal professional artist education. The most influential painter of naïve art was Henri Rousseau. He was a French post-impressionist painter in the Naive or Primitive manner. He was also known as "Le Douanier" or the customs officer. According to the definition of the Progressive Painters of the Renaissance, the naïve "are an awkward relationship to the formal qualities of painting, especially not respecting the three rules of perspective".