Talisse and I have been thinking about the famous maxim from John Stewart Mill’s On Liberty that

He who knows only his own side of the case, knows little of that. His reasons may be good, and no one may have been able to refute them. But if he is equally unable to refute the reasons on the opposite side; if he does not so much as know what they are, he has no ground for preferring either opinion.

We call it Mill’s Maxim.  It’s a central feature of our Why We Argue book, and we have a short popular essay on it published in Think a few years back.  Over at Philosophy 15, we have a 3-part discussion of the maxim, where Talisse argues that the maxim has two components.  First, it’s an epistemic thesis – that evidential assessment is comparative, and so to know the case for one’s view, it’s always how one view handles the relevant evidence compared to the competitors.  Second, it’s a semantic thesis – that understanding a view is to understand it contrastively, in terms of the views it must exclude.

In the spirit of the maxim, in the subsequent videos I then subject the view to a series of objections and contrasts in terms of how the view may be supererogatory instead of obligatory, how it may overplay the necessity of contrasts for comprehension, and whether the maxim puts us in danger of falling for really bad views.

Finally, there’s a question of whether the demands of following Mill’s Maxim places unnecessary or undue burdens on members of vulnerable groups.