Disagreement can be deeply unsettling. While it seems arrogant to ignore the opposition of other people, to lack confidence in the position dictated by one’s own evidence is spineless if not irrational. This has led many to propose rubrics distinguishing between disagreement that can be ignored and disagreement that should be taken seriously, but such rubrics produce hypocrisies and contradictions. Others have adopted a more relativistic approach, claiming that the incompatible views of other people should be tolerated. However, to say that we should ‘agree to disagree’ would be to deny that there is a conflict between the incompatible positions of different people—as long as I believe that what I know is contradicted by you, I cannot pretend our difference does not matter.

Incompatible positions matter because they are both about the same thing, the same world. This is why disagreement is disturbing—it indicates that another person shares the world I live in, and that, precisely because that person really is a different person, their view of it may not accord with my own.

It is impossible to explain the paradox of disagreement on the level of the fully formed thoughts comprising a disagreement in each case; to understand disagreement it is necessary to explain the ambiguous structure of the evidence on which the judgments comprising it are based. In each case, the basis of a judgment is an act of consciousness, which is about things belonging to the objective world, and yet exists in an individual’s own conscious activity, that the paradox of incompatible views on the same thing, which is to say, disagreement, effects us.