Ms Martin's dementia interferes with her insight and it may be considered acceptable to override her autonomy by reference to the principle of non-maleficence - the requirement to prevent harm.
The research points out that smoking may cause the risk of ablepsia, brain injury in old age, Alzheimer's disease and other kinds of dementia among old people.
Throughout the episode everything he says is brushed away as just the ramblings of someone with the disease but knowing what we know it becomes all the more obvious that he's in control.
That's why your muscles can start to atrophy if you don't use them for long enough, and why failing to stay active and learn new things can greatly increase the risk of developing dementia as you get older.
Those who don't want to descend into the indignity of extreme dementia, or doubt the ability of palliative care to ease their exit from life, will come here when the time is right.