The question of how much free expression to tolerate hardly came up until the modern era. The creation in Europe of the printing press changed that and made expression a threat to long-standing social institutions. The nature of the new technology made it impossible to fully control the flow of books, pamphlets, and other printed material, but European governments tried. The argument in favor of a free press ultimately emerged, and the practice itself was institutionalized, mostly in Great Britain and northwestern Europe. The chapter emphasizes the self-regulating argument for free communication, that ideas beyond science would be improved if they must be subject to readers’ scrutiny. Particular attention is paid to Milton, Struensee and John Stuart Mill. The arguments made in favor of the broad protection of freedom of speech that prevail in much of the world are shown to have significant self-regulating components.