The irrationality of disgust suggests it is unreliable as a source of moral insight. There may be good arguments against gay marriage, partial-birth abortions and human cloning, but the fact that some people find such acts to be disgusting should carry no weight.

Some scholars argue that although the brain might contain neural subsystems, or modules, specialized for tasks like recognizing faces and understanding language, it also contains a part that constitutes a person, a self: the chief executive of all the subsystems.

Morality is often seen as an innovation, like agriculture and writing. From this perspective, babies are pint-sized psychopaths, self-interested beings who need to be taught moral notions such as the wrongness of harming another person.

Part of the satisfaction of tattling surely comes from showing oneself to adults as a good moral agent, a responsible being who is sensitive to right and wrong. But I would bet that children would tattle even if they could do so only anonymously. They would do it just to have justice done.

In the past, there was active discrimination against women in science. That has now gone, and although there are residual effects, these are not enough to account for the small numbers of women, particularly in mathematics and physics.

Just as Darwin discovered the law of development of organic nature, so Marx discovered the law of development of human history: the simple fact, hitherto concealed by an overgrowth of ideology, that mankind must first of all eat, drink, have shelter and clothing, before it can pursue politics, science, art, religion, etc.

In science, every question answered leads to 10 more. I love that science can never, ever be finished. From a young age, people think, 'Science is hard and boring.' We don't tell children, 'Yes, you have to learn these formulae and theorems, but then you go on to learn about nuclear reactions and stars.'

The basic scientific conclusions on climate change are very robust and for good reason. The greenhouse effect is simple science: greenhouse gases trap heat, and humans are emitting ever more greenhouse gases.