For the mystics of the fifteenth century, it was the idea of the soul as bark, tossed on the sea of infinite desires, surrounded by sterile attachments and ignorance on all sides, and distracted by the meretricious sparkles of knowledge, in the midst of the great unreason of the world a boat at the mercy of the great madness of the sea, unless he drops anchor on the solid ground of faith, or spreads its spiritual sails so that so that the breath of God might bring it home to port.