PREFACE

—ably. For indeed, both these and other similar matters can be understood through specific rules and taught and learned by a fixed method. This is proven not only by the books written on these subjects, but also by the many most illustrious examples provided by many great men—both the ancients, as far as our knowledge and reports go, and more recent figures. Since these examples are already quite well known to the learned class, for whom these works are published, we judge it unnecessary to present them here at this time.

Furthermore, it is a significant part of the political and military arts, and others of that kind, to be able to hide those plans which could harm us if they became known to the enemy, and to communicate them to friends in such a way that they cannot be discovered by any means—neither by a dishonest courier nor by the enemies themselves, should the messages entrusted to them happen to be intercepted.

For this reason, both ancient and certain modern wise men have applied their skill to devise several stratagems original: "stratagemata," referring to clever tricks or schemes used to outwit an opponent, particularly in a military context for this purpose, as well as for other ways to secretly convey the hidden thoughts of the mind.

However, as to who has gathered, invented, and published more numerous and more ingenious methods, there is no one today, as far as I know, who stands above Giambattista della Porta original: "Io. Baptiſta Porta" (1535–1615), a famous Italian polymath and cryptographer, a most learned man. For this reason, when I saw that his books on secret writing original: "de furtiuis literarum notis," the title of Porta's landmark 1563 work on cryptography—commonly titled On Ciphers original: "de Ziferis"—were being greatly sought after by those devoted to the liberal arts...