I have explained why free speech is a good idea if you wish to convince other people of the truth of your position. But it is also something that you should support even if you do not know what the true position is. Free speech helps those who do not know the correct position because it permits exploration of all alternatives, clear consideration of the evidence and an open assessment of the state of our knowledge.
Free speech is good because it permits a clear exploration of all possible positions on a topic. For example, the position that the earth is flat is not a serious scientific opinion. But consideration of that position can show just how strong the evidence for a round earth is. This is also true for fringe topics, rejected positions and other positions. In addition, a consideration of all topics may make us aware of positions that we have not considered or positions that have been ignored because they were similar to rejected positions. For example, the position that men are better than women generally is a rejected position. But the position that men are better than women at math is a different position. Finally, a clear consideration of the positions can clarify just how strong one’ s favored position really is.
Free speech is good because it permits a clear consideration of the evidence. Each position about a topic has evidence supporting it or contrary to it. A clear consideration of this evidence regardless of what the position happens to be results in a clear appraisal of how much support a position really has and what the nature of the support really is. For example, the position that black people are mentally inferior did at one time have some evidence supporting it. A clear consideration of that evidence shows that there is little solid evidence that black people are mentally inferior. Although the position is disgusting to us, a clear and rational appraisal of evidence results in a rational rejection of the position. If we rejected the position on any other ground, then we would still have some rational doubt about whether or not our rejection was a good idea.
Free speech also allows an open assessment of the state of our knowledge. It may be that none of the current positions in a topic are well-supported by the evidence. Rather than some sort of misguided loyalty to a position, we should simply acknowledge that our knowledge is not currently great enough to determine which position is correct. We can also determine what sort of evidence would determine the truth and which, if any positions, are ruled out.
All of these advantages are limited and negated when our free speech is denied. Free speech is just the right to express any opinion at all. Free speech is instrumentally good because it helps us find the truth. A clear consideration of all positions, all evidence for those positions and the current state of our knowledge can help us find that truth. The degree to which free speech is restricted and limited will also limit our awareness and knowledge of what is true.
Now that I have given reasons for free speech, I will consider reasons to reject free speech. I will attempt to list and briefly discuss these reasons next.