What is human nature? Are we humans good or evil? To what extent is the character of a person produced by heredity, and to what extent by environment? Is competition more central to our existence than cooperation, or is it the other way around? How can a happy, peaceful and stable society be created? Are humans essentially the same as other animals, or are we fundamentally different? Should humans dominate and control nature, or should we be the custodians of nature? These questions are central to philosophy. Conflicting answers have been given by philosophers, scientists and religious leaders offer the centuries, from earliest times until the present.

The chemistry and physiology of emotions

Human emotions have a long evolutionary history. We share many emotions with our animal relatives - for example, mother love, fear and anger. Modern science has given us an insight into the chemistry and physiology of emotions. In our human brains, and in those of animals, there are billions of chemically moderated connections between neurons. These are called synapses. Whether or not a synapse “fires” and transmits its message to the next neuron depends on the chemical environment of the synapse, and this environment changes under the influence of hormones released by our glands, which are in turn influenced by our emotions.

Ethology: the science of inherited behavior patterns

Charles Darwin's book The Expression of Emotions in Man and Animals (1871) shows that he was aware that behavior patterns are just as reliably inherited as physical characteristics, and that they are similar within related groups of animals. For example, all members of the cat family show similar car-like behavior. Because of this pioneering book, Darwin is considered to be the founder of the science of ethology, the study of inherited behavior patterns.

More recently, in 1973, Karl von Frisch (1886-1982), Nikolaas Tinbergen (1907-1988), and Konrad Lorenz (1903-1989), shared a Nobel Prize in Physiology or Medicine. Karl von Frisch won his share of the prize for his studies of the waggle dance by which bees transmit information to their hive-mates. Tinbergen, who is famous for his studies of the instincts of birds, has pointed out that no modern ethologist would debate the question of whether heredity or environment plays a greater role in forming the character of an individual, since all learning is built upon a base of genetic predisposition, without which it would be impossible.

The third 1973 laureate, Konrad Lorenz, is most controversial, but also the most interesting of the three, since his famous book On Aggression casts light on why humans are so susceptible to militarism.

The dark side of human nature

Are humans good or evil? We can find evidence for both sides of human nature. It seems that humans can behave in both ways, depending on their education, and the circumstances in which they find themselves. In the recent killing of George Floyd, we see both sides of human nature. The brutal killing, and Donald Trump reaction show the dark side, while the worldwide anti-racist protests show human nature at its compassionate best.

Our collective shortsightedness: the climate emergency

There is a remarkable contrast in the way that governments around the world have responded to the COVID-19 pandemic and the way that they have responded to the climate emergency. The pandemic, which indeed represents an extremely grave danger to humanity, has produced a massive global response. Borders have been closed, airlines have become virtually inoperative, industries, restaurants and entertainments have been closed, sporting events have been cancelled or postponed, people have been asked to stay at home and practice social distancing, and the everyday life of citizens around the world has been drastically changed.

By contrast, let us consider the threat that if immediate action is not taken to halt the extraction and use of fossil fuels, irreversible feedback loops will be initiated which will make catastrophic climate change inevitable despite any human efforts to prevent it.

This threat is even more serious than the COVID-19 pandemic. Climate change could make much of the earth too hot for human life. It could produce a famine involving billions of people, rather than millions. And yet the world has hardly reacted at all.

A minority, for example the Scandinavian countries, have taken appropriate action. Most governments pay lip service to the emergency, but do not take effective action; and a few countries, such as the United States under Donald Trump, Bolsonaro's Brazil, and Saudi Arabia, deny that there is a climate emergency and actively sabotage action.

The world's net response has been totally inadequate. The Keeling Curve, which measures CO2 concentrations in the atmosphere, continues to rise, and the rate of rising is even increasing. What is the reason for this remarkable contrast between our strong reaction to the pandemic and our neglect of the climate crisis? Is it because we see clearly what is near to us and neglect whatever is far away? Or are powerful financial forces at work, controlling the mass media?

Sex and overconsumption

If we are to have a chance of avoiding catastrophic climate change, each of us must reduce his or her carbon footprint. Particularly in the wealthy parts of the world, we must simplify our lives and renounce overconsumption. Humans must stop using material goods as a means of social and sexual competition.

Human nature is best suited to sharing societies

What kind of society will make us happy and safe? What kind of society is sustainable? What kind of society is most in harmony with human nature? Our emotions have not changed much since the time when humans were hunter-gatherers, living in egalitarian groups that shared food whenever they were able to find it. There is much evidence that also today sharing and egalitarian societies are more happy than those with excessive individualism and competition.