Marius the Epicurean: his sensations and ideas is a historical and philosophical novel by Walter Pater, written between 1881 and 1884, published in 1885 and set in 161–177 AD, in the Rome of the Antonines. It explores the intellectual development of its protagonist, a young Roman of integrity, in his pursuit of a congenial religion or philosophy at a time of change and uncertainty that Pater likened to his own era.