Massimo Pigliucci:

Pigliucci introduces two different kinds of ethics: the consequentialist or utilitarian ethics (the greatest good for the greatest number of people, as formulated by Jeremy Bentham and John Stuart Mill) and, deontology, or rule-based ethics (most religious ethics is based on "commandments" and Kant's ethics is based on his "categorical imperative"). These two kinds of ethics are not mutually exclusive. Joshua Greene, a psychologist at Harvard, in "The Cognitive Neuroscience of Moral Judgment" (2009), has shown that people use one or the other depending on which part of the brain is activated, the one in charge of emotions (that prefers deontological decisions) or the one in charge of abstract reasoning (that tends to think like a utilitarian). The psychologist Jonathan Haidt in "The Emotional Dog and its Rational Tail" (2001) advanced a theory that our moral principles are due to emotions that are not ethical but simply evolved because they were functional to our survival. There is scientific evidence that serial killers have a brain that makes them more prone to violence, and this brain anomaly may be caused by a gene called MAO-A that has been found in several serial killers. In the right (wrong) circumstances a person with that gene is likely to become a killer. There is also some scientific evidence that damage to the ventromedial prefrontal cortex (VMPFC) can cause people to become psychopaths. Antonio Damasio discusses some of this in "Neuroscience and Ethics" (2007). The relation between reasoning and emotion is not clear though. Kant thought that reasoning influences emotion which than yields a moral judgment. Hume thought that emotion determines the moral judgment and after the fact we found a rational justification for it. John Rawls thought that moral judgment precedes both emotion and reasoning, and emotion and reasoning are simply two different ways to carry it out. Hobbes thought that human nature is far from moral and that's why we invented the state to keep peace among us. Pigliucci mentions other neurobiological studies of morality, notably Kristin Prehn's & Hauke Heekeren's "Moral Judgment and the Brain" (2009), but this is an area where scientific studies must be taken with a grain of salt because there is a new hypothesis every year.

At this point Pigliucci brings in Charles Darwin and Frans de Waal, who showed that altruism is widespread in nature. Biologists such as William Hamilton and Robert Trivers tried to explain altruism in purely selfish terms: it is better for my survival to have friends. In the 1990s neuroscientists discovered "mirror neurons" that could explain where empathy comes from.

Another philosopher, Peter Singer, thinks that animals may have indeed an instinctive sense of justice, but humans are alone in being able to reason about it. Human morality is therefore the sum of an emotional sense of justice, that evolved because it was useful to survival, and the ability to reason about it.

Having introduced the scientific foundations of our moral sense, Pigliucci then begins to draw conclusions. First of all, he thinks that none of the ethical approaches is absolutely correct, but a mixture of them could be. Pigliucci points out that deontology is about intentions of actions whereas utilitarianism is about consequences of actions. Both have problems. For example, deontologists can state that lying is bad, but sometimes it is good to lie in order to protect somebody's life from a killer. On the other hand, utilitarianists cannot predict all the possible consequences of an action, and therefore be certain that it will provide the greatest good for the greatest number of people. There is a third kind of ethics. Aristoteles thought that the meaning of life is a quest for eudaimonia, that Pigliucci translates as "flourishing" in order to distinguish it from Christian and Buddhism ascetisms (eudaimonia includes physical pleasure). In order to achieve eudaimonia you have to be virtuous. There is no prescription for the specific action, but a general prescription for how to live a life. And it is a lifelong project: virtue comes from practicing it.

Pigliucci thinks that human beings are not rational animals but "rationalizing" animals. We think about our actions, and we even think about our thoughts. Williams James was the first psychologist to popularize the notion that cognition is split in two: a fast intuitive emotional form of decision making and a slow rational form of decision making. When under pressure, we use intuitions.

Pigliucci discusses what trust we can have in science. Great thinkers from Hume to Russell have shown that induction is a weak method to determine reality . Popper's "falsification" approach risks killing discovery of new facts that will prove science correct (hence Kuhn's "paradigm shift" approach). Most scientific theories have been proven false, or at least insufficient, but that doesn't mean that science should be rejected. Pigliucci offers a way to work with its imperfection called "perspectivism": scientific theories are tentative, not final, and capture some important fact about reality.

Pigliucci then deal with the self and free will. The idea of moral responsibility is based on the idea that we have free will: it is the person who kills, not the gun, because it is the person who consciously decided to pull the trigger. But if you can prove that external factors "made" that person pull the trigger, then the person is no longer fully guilty. A mental illness is considered such an "external factor" because it weakens the will of the person, the power to control one's actions. It turns out that a psychologist, Libet, conducted experiments that proved a funny fact: we are aware of our decisions after our brain already sent the signal to execute them. Libet rescued free will by hypothesizing that the conscious "i" can still veto the action that has been mechanically decided by unconscious electrochemical processes, but that's far fetched. Pigliucci mentions another possible explanation of Libet's experiments: maybe they simply show how we become conscious of our unconscious (instinctive) actions. Neuroscientists are focusing on the parietal cortex as the neural correlate of decision making, the place where the brain makes decisions.

The broader issue, however, is whether the universe is deterministic or not. There are three possible answers: the compatibilists (the universe is deterministic but free will is still a possibility), the libertarian incompatibilists (the universe is not deterministic), and the deterministic incompatibilists (the universe is fully deterministic and free will is an illusion). Science (quantum mechanics) seems to show that the universe is not deterministic: it has a random foundation. But that hardly explains free will: "random" will is not "free" will. Pigliucci leans towards "compatibilism". Free will has a neural basis, because everything we are has a neural basis, but free will is a complex neurobiological phenomenon and in fact it is more than just one.

The chapters on love, happiness and eros and philia), friendship are not particularly interesting, nor convincing.

The story resumes when Pigliucci discusses our instinctive, neural-based sense of fairness and John Rawls' ethics (according to which we should continuously revise our judgments until we reach a state of equilibrium). The evidence that our brains are equipped with an hardwired sense of fairness is weak (Pigliucci cites only one study) but the connection with Rawls' ideas would be powerful. Rawls thought that justice "is" fairness without the scientific evidence that humans are equipped with this sense. Rawls' "maximin" criterion states: "to maximize the minimum level of resources that all have access to". (Scandinavian societies seem to be the best implementation of the maximin principle).

Along the way, Pigliucci debunks widely held myths about the "innate talent" (talent mostly comes from practice not genes), wine experts (experiments show that they are not any better than ordinary drinkers), psychiatrists and stockbrokers (data show that they are not any better than amateurs), as well as the idea that positive thinking helps achieve one's goals and the illusion that your political views are rational.

Pigliucci also explains mystical feelings, based on Michael Persinger's "Neuropsychological Bases of God Beliefs" (1987), and the neurological bases of out-of-body experience, via Olaf Blanke's "Stimulating Illusory Own-body Perceptions" (2002). Pigliucci, a skeptic when it comes to Dawkins' "meme", provides a (tentative) evolutionary explanation for the emergence of religion, as the accidental byproduct of two skills that evolved for other reasons: pattern seeking (the ability to make sense of patterns) and agency projection (the instinctive "theory of mind" that makes us see all moving things as sentient beings). But he invokes Socrates' famous argument against religion (that gods are irrelevant to morality and that our sense of morality is independent of what gods may mandate

Unfortunately, the last chapter is hard to swallow. He argues that the happiest countries are countries like Scandinavia and France (John Rawls' just states), but these turn out to be amond the countries with the highest suicide rates in the world; hardly a proof of happiness.