 Focusing on the incomparability of bearers of value has given rise to two lines of inquiry in the literature. The first concerns the relation between incomparability and vagueness; some argue that alleged examples of incomparability are better understood in terms of vagueness. The second concerns the range of comparative relations that can hold between two items; some argue that the Small Improvement Argument does not establish incomparability but rather that there are more value relations than previously believed. This section summarizes debate within each line of inquiry.