FAIRNESS SLIPPERY-SLOPE ARGUMENTS

When borderline cases form a continuum, if someone classifies a case at one end of the continuum, an opponent often challenges this classification by asking, “Where do you draw the line?” Sometimes this challenge is out of place. If I claim that Babe Ruth was a superstar, I will not be refuted if I can- not draw a sharp dividing line between athletes who are superstars and those who are not. There are some difficult borderline cases, but Babe Ruth is not one of them. Nor will we be impressed if someone tells us that the dif- ference between Babe Ruth and the thousands of players who never made it to the major leagues is “just a matter of degree.” What is usually wrong with this phrase is the emphasis on the word “just,” which suggests that dif- ferences of degree do not count. Of course, it is a matter of degree, but the difference in degree is so great that it should be marked by a special word.

There are other occasions when a challenge to drawing a line is appropri- ate. For example, most schools and universities have grading systems that draw a fundamental distinction between passing grades and failing grades. Of course, a person who barely passes a course does not perform very dif- ferently from one who barely fails a course, yet they are treated very differ- ently. Students who barely pass a course get credit for it; those who barely fail it do not. This, in turn, can lead to serious consequences in an academic career and even beyond. It is entirely reasonable to ask for a justification of a procedure that treats cases that are so similar in such strikingly different ways. We are not being tender-hearted; we are raising an issue of fairness or justice. It seems unfair to treat very similar cases in strikingly different ways.

The point is not that there is no difference between passing and failing. That is why this argument is not a conceptual slippery-slope argument. The claim, instead, is that the differences that do exist (as little as one point out of a hundred on a test) do not make it fair to treat people so differently (credit versus no credit for the course). This unfairness does not follow merely from the scores forming a continuum, but the continuum does put pressure on us to show why small differences in scores do justify big differences in treatment.