The primary purpose of this chapter is to examine the nature of self in dementia; in particular, how the cognitive deficits inherent in dementia influence the conception of what it means to be human. Alzheimer's disease is the result of global cortical atrophy with demonstrable deterioration of cognitive functions including memory, visuo-spatial functions, language and adaptive behaviour. People living with dementia, however, do not usually claim to be somebody else. Their numerical identity is never in question and their distinctiveness from other human beings is without doubt. For Hume, the mind is a concept rather than a thing and the self is the conglomeration of perceptions. In this account, a centre of experience that is a self, is illusory. However, Hume's account ignores the agentic aspect of the self and concentrates exclusively upon the perceptual aspects. The role of language, from which arises the capacity to give a narrative account is missing from Locke and Hume's accounts.