Persecution, then, gives rise to a peculiar technique of writing, and therewith to a peculiar type of literature, in which the truth about all crucial things is presented exclusively between the lines. That literature is addressed, not to all readers, but to trustworthy and intelligent readers only. It has all the advantages of private communication without having its greatest disadvantage—that it reaches only the writer's acquaintances. It has all the advantages of public communication without having its greatest disadvantage—capital punishment for the author. But how can a man perform the miracle of speaking in a publication to a minority, while being silent to the majority of his readers? The fact which makes this literature possible can be expressed in the axiom that thoughtless men are careless readers, and only thoughtful men are careful readers. Therefore an author who wishes to address only thoughtful men has but to write in such a way that only a very careful reader can detect the meaning of his book. But, it will be objected, there may be clever men, careful readers, who are not trustworthy, and who, after having found the author out, would denounce him to the authorities. As a matter of fact, this literature would be impossible if the Socratic dictum that virtue is knowledge, and therefore that thoughtful men as such are trustworthy and not cruel, were entirely wrong.
Another axiom, but one which is meaningful only so long as persecution remains within the bounds of legal procedure, is that a careful writer of normal intelligence is more intelligent than the most intelligent censor, as such. For the burden of proof rests with the censor. It is he, or the public prosecutor, who must prove that the author holds or has uttered heterodox views. In order to do so he must show that certain literary deficiencies of the work are not due to chance, but that the author used a given ambiguous expression deliberately, or that he constructed a certain sentence badly on purpose. That is to say, the censor must prove not only that the author is intelligent and a good writer in general, for a man who intentionally blunders in writing must possess the art of writing, but above all that he was on the usual level of his abilities when writing the incriminating words. But how can that be proved, if even Homer nods from time to time?