What are Mills four main arguments in defence of freedom of speech?
The Infallibility Argument says we can never assume that the views we hold are true. Nobody is infallible, therefore nobody can be certain of being entirely correct. We can never be justified in suppressing views contrary to our own, because it is always possible that we are at fault, and these contrary views are in fact the truth. “There is quite a gulf … between our being certain of a view, and the view being certain” [u1-2: p183] An example from history is that of Galileo, who was imprisoned as a heretic by the Catholic Church for advocating Copernicus’ theory that the Earth orbited the Sun. The ruling authorities assumed their own infallibility, whereas – as we now know – they were in fact wrong. Note that we are no more justified now in suppressing geocentric models than the church was in suppressing Galileo’s heliocentric model, as it may turn out that we are in turn wrong. No matter how much evidence we have, or think we have, we can never be justified in assuming our infallib
