  The most extreme form of discontinuity is incommensurability or incomparability, when two values cannot be ranked at all. Pluralists differ on whether pluralism entails incommensurabilities, and on what incommensurability entails for the possibility of choice. Griffin denies that pluralism entails incommensurability (Griffin uses the term incomparability) whereas other pluralists embrace incommensurability, but deny that it entails that rational choice is impossible. Some pluralists accept that there are sometimes cases where incommensurability precludes rational choice.  We shall return to these issues in Section 4.