Psychopathology, Personal Identity and David Hume

Consider our idea of 'personal identity'. Of what simple ideas is it compounded, and from what impressions are they derived? David Hume was unable to answer the questions to his own satisfaction, and yet he could have answered them, I think, and many more, had he considered the implications of an off-hand remark that he made early on within his Treatise of Human Nature: " . . . in madness . . . our ideas may approach to our impressions" (page 2), for what is 'madness', succinctly, but a loss of personal identity? Hume's Treatise of Human Nature is mistitled, for it remains unconcerned with the possible abnormalities of the mind. I suggest within this essay, however, that had Hume considered the possibilities of abnormality implicit in his theory of the normal mind, he could not only have solved the problem of personal identity but established with remarkable accuracy the foundations of psychopathology as well.