Unit Overview

This week we attempt to understand a little about the science of morality before moving on to understanding what morality is from a philosophical perspective and various philosophical theories of morality. In short, morality, from a scentific perspective, is a set of instincts and emotions that help species raise their young and live together and cooperate in groups.


In the Darwin reading he argues that humanity’s highest faculty, it’s moral sense, is present, in rudimentary form, in other social species. The “common themes in primate ethics” reading gives you a brief overview of some of the moral capabilities that we share with primates. The evolutionary social psychology reading is not required but just provided if your curious to learn more about the topic, although you may find it helpful.

Moral Emotions

David Hume (1711-1776) was the first philosopher to really focus on the role of emotions in moral judgements. He argued that abstract reasons don’t motivate action. And that since moral beliefs are very motivating they must not be abstract reasons but rather emotions. I, his book A Treatise on Human Nature, he famously said that reason was “the slave of the passions.”

Approximately a hundred years later Charles Darwin would publish his book The Origin of Species (1859) in which he would explain his theory of evolution. Part of what he would seek to explain with his theory of evolution was social and moral behavior.

The basic idea is that since the beginning of our species we have lived in social groups. These social groups are made possible by our ability to cooperate together and to care for others, most importantly our children but also other members of our tribe or family. Our sense of empathy and our concern for fairness or justice are necessary for us to cooperate and live together. Since the dawn of humanity, humans have been governed by rules that dictate what is morally permissible. As these groups got bigger the rules become laws. Legal and criminal justice systems arose to enforce the laws. Societies across the globe in countries like Greece, Rome, China, India, Mesopotamia and many other places all had such systems. These large societies required people to be able to live together. Our best scientific evidence makes it clear that humanity’s ability to live together, to care for each other, to cooperate comes from our ancestors and distant relatives in various species. Without the cognitive and emotional capacity for moral behavior, social interaction and society itself would not be possible.

The Leopard and the Baby Baboon

I really like this video as it illustrates the power of emotional instincts. In this particular case it is the maternal instincts of the leopard that are triggered by the cries of the baby baboon.

Other Displays of Animal Emotion


Frans De Waal on Moral Behavior in Animals

In this video De Waal gives us an overview of some of the moral capacities that animals possess and use to cooperate and solve tasks. The view of animals he presents here, being social and cooperative, is in contrast to the traditional view of animals and humans as being entirely selfish, vicious, and power hungry. He specifically identifies two features of animal behavior as the foundation, or the precursor, of moral behavior in human beings. And, incredibly, showing that some primates have a rudimentary sense of fairness.

Evidence for Moral Emotions in Humans

One could certainly teach an entire class on moral psychology and entire academic careers are dedicated to studying the topic, but we will have to be content with just a brief discussion of human moral psychology. The video below shows that morality in humans is not a matter of reasoning but that human infants possess powerful moral emotions:

That research indicates humans come into this world with a powerful set of emotions and instincts that help us navigate the social world that we inhabit.

One thing to keep in mind is that human moral psychology is double edged sword. While we do have powerful instincts to care for others and to help others we also have powerful emotional instincts to harm others. We like to see people we see as bad punished. And often we see entire groups as bad. The simplest summary of human moral psychology is that we are altruistic towards those that are in our group (race, religion, nationality, etc.) but that we tend to have very little regard and often hate members of other groups. Think about all the instances of slavery, genocide, and racism throughout history and still existing to this day. Such emotions are the legacy of our tribal past in which we had to fight with other groups to survive. To survive our ancestors had to be able to care for each other and help each other find food, hunt, and build shelter, and they had to fight members of other tribes for survival, often to the death.

Right now there are thousands of children dying in third world countries of preventable diseases, but we don’t really care about them. That fact doesn’t move us. This is because our moral emotions were designed by natural selection to care about those who are close to us, both in physical proximity and group membership.

In some ways, the fundamental challenge of being a good person is to learn to care about people beyond those who are closest to us. Can we as a species transcend tribalism?

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