PREFACE

...to these books of Porta, one must compare either the diligence of his method, the sheer multitude of types [of secrets], or the clarity with which he explains certain things. Indeed, we do not deny that reading both works together The publisher is likely referring to Johannes Trithemius’s Polygraphia, mentioned at the end of the previous page, and Porta’s own work. might be done with no small profit.

And indeed, if for no other reason, then certainly for this one, Porta must be read thoroughly by those devoted to military and civil prudence, and indeed by all those who have a mind to investigate the secrets of others. For while it is within our power not to use this art ourselves, we cannot prevent adversaries, enemies, and others from employing it.

But if it should happen—a thing for which students of military and civil affairs must greatly strive—that hostile stratagems original: "stratagemata"; here referring to encrypted messages or secret military maneuvers of this kind or other such writings should fall into our hands, we will be able to recognize and uncover them with Porta’s help. For this also must be counted among those features in which these books far excel the published works of others on this subject: that they explain, with singular industry and skill, the method not only for inventing secrets of this kind, but also for unfolding original: "evolvendarum"; referring to the process of deciphering or unravelling a coded message those used by others, as far as it is possible to do so.

What of the fact that these books render most clear very many passages of ancient writers that speak of this art, or are derived from it, which are often otherwise quite obscure?