KEITH WHITTINGTON: John Stuart Mill was an extraordinary and influential thinker in the early 19th century in England. He was something of a radical within his society at the time and, as a consequence, was very interested in the ability to to develop and communicate radical ideas that were outside the mainstream, because he was interested in a lot of those ideas himself, and he was much more interested in how a free society should operate the ability of people to think for themselves in a free society, and sometimes run against the grain of public opinion and mainstream thought in general.

He offered a variety of arguments about why it is we ought to value that kind of speech, those kinds of spaces, that kind of robust debate. So one of those arguments I characterize as an argument driven by humility. That is, that part of what Mill wanted to remind us is that we all might be mistaken, that our own understanding is limited. Our own set of ideas are very limited. And that we can learn from each other. And we can learn from others who have different ideas than ourselves. But that requires some willingness to accept the possibility that we, in fact, might be mistaken. And of course, we walk around most of the time with the belief that we are upholding a set of correct ideas, that we think we know our own minds. We think the ideas we hold are true. That's why we hold them in the first place. And so it can be challenging to go into a conversation and go into a discussion, go into a public space and accept the possibility that we might be wrong. But Mill wanted to emphasize that it's only by accepting that possibility that we're wrong that we can have the opportunity to learn. And it's important for our own sake that we be able to continue to learn and grow by talking to people with different ideas and being genuinely open to the possibility that they might persuade us. They might show the flaws in our ideas. They might expose our mistakes. And as a consequence, they might help us make progress.

But he also constructs an argument that's really grounded instead on a concern with arrogance of others. Here, the concern is not so much that we be willing to hear from people that we disagree with because we accept the possibility that we might be wrong. But instead, he wants to speak to our instincts to want to suppress opinions that we find disagreeable or dangerous so that no one else can hear them, instead. And this is fundamentally a paternalistic concern, a concern that we're worried about other people, that they might be misled by bad ideas. And so even if we think that we ourselves are capable of separating good ideas from bad ideas, and so as consequence, we should be able to hear a wide range of views and arguments, we might be much less comfortable that other people can make the same distinctions, will come to good decisions, exercise good judgment when listening to those ideas. And so as a consequence, there's a certain arrogance where we want to impose our own beliefs on others and shield them from the opposition; shield them from listening to the critics so that the only voices they hear are our own. And it's difficult to resist that tendency and that instinct, precisely because when we're thinking about what ideas in society we find as wrongheaded, disturbing, maybe dangerous, it becomes all the more tempting to think, when confronted with that dangerous idea, that we shouldn't expose anyone else to that dangerous idea because they might be polluted by it. They might believe it. And they might even want to act on it.

And finally, Mill offers an argument that I characterize as an argument from conviction, which is to say that he says, we have a set of ideas that we walk around with. And we think they're probably right. We assume oftentimes they're right; we haven't thought about them very carefully. And they may be very deeply held ideas. They may be central to our belief system, our value system. More generally, they may be crucial to how we think about the world and how it operates, more generally. But oftentimes, we don't have a lot of reason to think about those ideas very carefully. We haven't explored them or thought about them very carefully ourselves. Instead, we've received them from others. We've taken it for granted they're probably true, and we've moved on. But he emphasizes that we don't really know how true those ideas are. We don't know how confident we ought to be about the truth of those ideas until we've seen them tested in intellectual battle, and until we've seen critics go after them with hard arguments, with counter evidence, with objections, and we've seen how well those ideas can weather that kind of storm. Can our ideas stand up to criticism and skeptical inquiry? And he says we shouldn't be very confident in ideas that we are not willing to expose to those kind of criticisms. That it's precisely the ideas that we've seen weather the criticism that we ought to be confident about.

And so as a consequence he encourages us to think that if we want to have real confidence in our beliefs as individuals, but also as a society, that we should be particularly willing to expose our ideas to the harshest critics we can find because those critics will help us, and they will help us be more confident in the strength of our own ideas. And sometimes they will also show us the weaknesses of our ideas and force us, then, to think more carefully about them and force us to build better and more robust supports for those ideas. So we will come away more sophisticated thinkers with more carefully held and carefully considered ideas than we went into those conversations with.