John Ruskin, the eccentric painter and polymath, would have delighted in the snarkiness of this particular birthday party. To celebrate his bicentenary, The Huntington presents 16 works by Ruskin, his friends, and his enemies. A champion of the arts, Ruskin was a great support to his many friends. But his advice, ginned up by his enthusiasm, could be cutting. As a professional art critic, he was even worse. James McNeil Whistler sued for libel after Ruskin likened his work to “flinging a pot of paint in the public’s face.” While “frenemies” may seem like an insulting theme, it points up Ruskin’s passion, the ferocity of his commitment to art and intellect, and the complexity of his influence. —C.J.F.