Suppose you work for your country's main security agency and you have apprehended a man who you
strongly suspect is involved in a terrorist conspiracy. You have some reason to believe that other
members of his group are planning a major attack that will cost many lives, but the man refuses to
identify them despite extensive interrogation. Your moral dilemma is whether you should torture the
terrorist in order to extract from him information that might prevent a major disaster.
Now you have to make a decision that is not just about satisfying your personal goals. Rather, you
have to deal with a conflict between competing ethical principles: the strict rule that torture is always
wrong, and the more flexible rule that you should pursue the greatest good for the greatest number of
people. You now have to face the last major philosophical question identified in chapter 1: what
makes actions right or wrong?
Some philosophers such as Nietzsche have rejected the whole idea of moral objectivity. Maybe
there are no absolute standards of right and wrong, so that morality is relative to particular
individuals, situations, or cultures. Perhaps we should say that torture is wrong if your society thinks
so, but OK otherwise. Or even more subjectively, perhaps torture is wrong for you if you don't like it,
but fine for me if I do. Many religious thinkers have thought that these kinds of moral relativism
would unavoidably result from the rejection of theology. Without God, anything is permissible.
In contrast, my aim is to develop a theory of objective morality that fits well with a general
naturalistic, evidence-based approach and with particular findings about how brains think. Many
philosophers would view this as a hopeless task, because of Hume's famous injunction that you
cannot derive an ought from an is. I do not claim to have produced such a derivation, as Hume was
undoubtedly right that there are no sound deductive arguments that can take you from empirical facts
about the world to the acceptance of particular or general moral judgments.
Rather, I will move toward a moral theory that is highly coherent with what is known about how
brains make moral decisions, and with other psychological and social facts. This moral theory should
be a central part of a general account of wisdom and why life is worth living. As in chapter 8, the
crucial bridge between is and ought is provided by human needs that point to a general theory of what
makes actions right and wrong. I will discuss brain mechanisms such as mirror neurons that enable
and encourage people to care about others as well as themselves.