No attempt is made in the following pages to submit to historical treatment the vast and varied mass of printed matter which Cardan left as his contribution to letters and science, except in the case of those works which are, in purpose or incidentally, autobiographical, or of those which furnish in themselves effective contributions towards the framing of an estimate of the genius and character of the writer. Neither has it seemed worth while to offer to the public another biography constructed on the lines of the one brought out by Professor Henry Morley in 1854, for the reason that the circumstances of Cardan's life, the character of his work, and of the times in which he lived, all appeared to be susceptible of more succinct and homogeneous treatment than is possible in a chronicle of the passing years, and of the work that each one saw accomplished. At certain junctures the narrative form is inevitable, but an attempt has been made to treat the more noteworthy episodes of Cardan's life and work, and the contemporary aspect of the republic of letters, in relation to existing tendencies and conditions, whenever such a course has seemed possible.