In 1975 the founder of a new field of biomedical ethics came up with 15 criteria by which someone’s “humanhood” could be judged.
Among the qualities defined by Dr Joseph F Fletcher, an ordained Episcopal priest in the US and a controversial professor of ethics who espoused the virtues of euthanasia, were some minimal intelligence, self-awareness, self-control, a sense of time and concern for others.
These, he said, distinguish us from our animal ancestors.
