A variety of important cultural figures, both Writers and artists, were influenced by Swedenborg's writings, including Robert Frost,Johnny Appleseed, William Blake, Jorge Luis Borges, Daniel Burnham, Arthur Conan Doyle, Ralph Waldo Emerson, John Flaxman, George Inness, Henry James Sr., Carl Jung, Immanuel Kant, Honoré de Balzac, Helen Keller, Czesław Miłosz, August Strindberg, D. T. Suzuki, and W. B. Yeats. His philosophy had a great impact on the Duke of Södermanland, later King Carl XIII, who as the Grand Master of Swedish Freemasonry (Svenska Frimurare Orden) built its unique system of degrees and wrote its rituals. In contrast, one of the most prominent Swedish authors of Swedenborg's day, Johan Henric Kellgren, called Swedenborg "nothing but a fool". A heresy trial was initiated in Sweden in 1768 against Swedenborg writings and two men who promoted them.