What really is the nature of suffering? Three problems with Eric Cassell's concept of distress

Eric Cassell famously defined suffering as a person's severe distress at a threat to their personal integrity. This article draws attention to some problems with the concept of distress in this theory. In particular, I argue that Cassell's theory turns on distress but does not define it, which, in light of the complexity of distress, problematizes suffering in three ways: first, suffering becomes too equivocal to apply in at least some cases that Cassell nevertheless identifies as suffering; second, Cassell's account does not explain what sort of experience suffering is, resulting in theoretical and practical difficulties in distinguishing it from other medical conditions; third, there is good reason to believe that, in medical contexts, 'distress' just means 'suffering' or some cognate concept not yet distinguished from it, rendering Cassell's theory circular. I consider a rebuttal to my objections and reply, concluding that Cassell's theory of suffering needs a definition of distress to settle what the nature of suffering really is.