Mill’s On Liberty (1859) offers one of the most powerful arguments for the progressive effects of liberty of speech and of the press. When interpreted within the contexts of his other writings, Mill’s approach is notable for three exceptions to its general liberty-defending rule. Mill appears to exempt defamatory speech from protection; he does not defend speech that incites violence; and, most importantly, Mill argues that the liberty principle does not apply in precisely the democratising places where progressive liberty of speech and press promise the greatest short-term benefits. I argue that Mill’s theory is a near-absolutist and conditional theory. Firstly, by interpreting defamation and incitement narrowly, Mill’s theory of free speech becomes nearly absolutist. Secondly, Mill’s comparative experience with British India, coupled with an unempirical philosophy of history borrowed from Auguste Comte, makes Mill’s theory conditional. In my conclusion, I argue that Mill’s near-absolutist, conditional theory should be updated. Mill’s theory of liberty remains very defensible but his theory of liberty of speech and of the press should be released from its straitened conception of British Indian publics. Publics were very much in existence in English and vernacular circles in Mill’s India, even if they were not recognised by Mill. Mill’s theory should also be liberated from the ahistorical and unempirical Comtist philosophy of history that contributes to the annulment of existing publics. However, to do so risks implying that the liberty principle can be applied to all societies indiscriminately at any place or time. A truly utilitarian theory of the useful effects of free speech and freedom of the press is instead relative to its historical and political circumstances.