Typically, defenders of experiments on animals do not deny that animals suffer. They cannot deny the animals' suffering, because they need to stress the similarities between humans and other animals in order to claim that their experiments may have some relevance for human purposes. The experimenter who forces rats to choose between starvation and electric shock to see if they develop ulcers (which they do) does so because the rat has a nervous system very similar to a human being's, and presumably feels an electric shock in a similar way.

So far as this argument is concerned nonhuman animals and infants and retarded humans are in the same category; and if we use this argument to justify experiments on nonhuman animals we have to ask ourselves whether we are also prepared to allow experiments on human infants and retarded adults; and if we make a distinction between animals and these humans, on what basis can we do it, other than a bare-faced - and morally indefensible - preference for members of our own species?

There is no humane slaughter requirement for wild fish caught and killed at sea, nor, in most places, for farmed fish.

So why don't we make ourselves the last generation on earth? If we would all agree to have ourselves sterilized then no sacrifices would be required - we could party our way into extinction!

My view is different from this, only to the extent that if a decision is taken, by the parents and doctors, that it is better that a baby should die, I believe it should be possible to carry out that decision, not only by withholding or withdrawing life-support - which can lead to the baby dying slowly from dehydration or from an infection - but also by taking active steps to end the baby's life swiftly and humanely.

The traditional view of the sanctity of human life will collapse under pressure from scientific, technological and demographic developments.

...chimpanzees, bonobos, gorillas, and orangutans are thinking, self-aware beings, capable of planning ahead, who form lasting social bonds with others and have a rich social and emotional life. The great apes are therefore an ideal case for showing the arbitrariness of the species boundary. If we think that all human beings, irrespective of age or mental capacity, have some basic rights, how can we deny that the great apes, who surpass some humans in their capacities, also have these rights?