Sir

Several texts published in Nature, notably a leading article devoted to the opinion of the French Consultative Ethics Committee (Nature 387, 321 321 1997 & Nature 387, 324 324 1997) and John Harris's letter (Nature 387, 754 754; 1997), discuss the argument that application to man of asexual reproduction and cloning represents an affront to human dignity.

However, the two main arguments I set out in my Commentary (Nature 386, 119 119; 1997), and which were expanded in the French ethics committee opinion, were not accurately reported.

One of the components of human dignity is undoubtedly autonomy, the indeterminability of the individual with respect to external human will. No man or woman on Earth exists exactly as another has imagined, wished or created.

The birth of an infant by asexual reproduction would lead to a new category of people whose bodily form and genetic make-up would be exactly as decided by other humans. This would lead to the establishment of an entirely new type of relationship between the ‘created’ and the ‘creator’, which has obvious implications for human dignity.

Harris contests the validity of arguments based on the Kantian principle. But Kant did not say that respect for human dignity requires that an individual is never used as a means, but that an individual must never be used exclusively as a means. The word ‘exclusively’ makes all the difference between idle talk and one of the fundamental principles of modern bioethical thought.

The workman is indeed the means for doing work, the person who donates an organ is the means for saving the patient, but they are never exclusively a ‘means’, but also ends in themselves.

The creation of human embryos exclusively as a means, uniquely as a source of therapeutic material, would therefore seem in contradiction of Kant's principle, whose universality is far superior to that which Harris dismisses by omitting the word ‘exclusively’.

In reality, the debate is about the status of the human embryo and its rights as a human individual, and the answers to this question differ greatly both between and within nations. In general, however, all those who would legitimize de novo creation of human embryos for research or preparation of therapeutic material base their position on their belief that the embryo is not a human individual, without calling Kant's principle into question.

Is Harris announcing the emergence of a revisionist tendency in bioethical thinking?