To turn the other cheek is to teach would-be cheats that cheating pays.

My fear is that that's what's going to happen with robotics and the military. Importantly, this discussion has to involve not just the scientists, but also the political scientists. It's got to be a multidisciplinary discussion. You can't have it be another repeat of what happened with the people working on the atomic bomb.

The newspapers do little better. Their coverage of nonhuman animals is dominated by "human interest" events like the birth of a baby gorilla at the zoo, or by threats to endangered species; but developments in farming techniques that deprive millions of animals of freedom of movement go unreported.

In appropriate circumstances we are justified in using humans to achieve goals (or the goal of assisting animals).

Without in any way minimising the economic and psychological blow that people experience when they lose their jobs, the unemployed in affluent countries still have a safety net, in the form of social security payments, and usually free healthcare and free education for their children. They also have sanitation and safe drinking water.

With the eventual acceptance of Darwin's theory we reach a modern understanding of nature, one which has since then changed in detail rather than in fundamentals. Only those who prefer religious faith to beliefs based on reasoning and evidence can still maintain that the human species is the special darling of the entire universe, or that other animals were created to provide us with food, or that we have divine authority over them, and divine permission to kill them.

I do not believe that it could never be justifiable to experiment on a brain-damaged human.