Anicius Manlius Severinus Boethius (475 (estimate) - 524)
Was a Roman statesman and philosopher. He wrote his most famous work, The Consolations of Philosophy, in prison while awaiting his execution.
He also had written some texts on music theory, geometry, and theology. While Boethius was a Christian, The Consolations of Philosophy is remarkable in that it has no reference to Christian beliefs, and is of a strictly philosophical nature.
This is a nice quote attributed to him: "Of all misfortune, the worst kind of fate is to have been happy. "