Abstract
People with dementia often undergo profound changes in attitudes and behavior. Following such changes, it can be difficult for carers to know the weight that should be attached to advance directives: should the person’s apparent current choices be respected or should they be overridden by choices that were made before the dementia developed? This question raises further questions about the nature of autonomy and identity and how these are affected by the various kinds of functional damage caused by dementia. Ronald Dworkin answered this question by arguing that identity is based around what he terms “critical interests” and that these interests are formed prior to the onset of dementia, which means that prior decisions (or precedent autonomy) should be respected. Agnieszka Jaworska has criticized this view and argued that people with dementia retain the capacity to form new critical interests because they retain the capacity to value. Christine Korsgaard’s account of personal identity shows that both Dworkin and Jaworska are partly right, but also that judgments about whether or not a given decision is in keeping with a person’s identity may be yet more difficult than either suggest. This indicates the need for further philosophical and ethical analysis of this area of medicine.