All human beings, says the Universal Declaration of Human Rights, are born free and equal in dignity and rights. But who is the ‘human’ of human rights? The Universal Declaration, and other official human rights documents, take the answer to be self-evident. What could be more obvious? The ‘human’ bearer of rights is a universal, timeless figure – human rights are the rights we are accorded simply for being Homo sapiens.

It’s an attractive idea. Without some divine being to underpin our morality, rights appear very fragile, subject to fluctuating social mores and political power. By establishing human rights as a matter of