The brains behind morality: a lecture by prof. Patricia Churchland

To the untrained eye, rats, Daniel Dennett and neocortices do not seem to have anything in common. Within the hour, however, renowned professor emerita Patricia Smith Churchland from the Department of Philosophy of the University of California (San Diego), eloquently linked these offbeat topics together in her compelling lecture “The brains behind morality”. 

It’s nature!

With great enthusiasm Churchland spoke of an experiment Peggy Mason had conducted on rats. During this experiment she imprisoned one rat in a Plexiglas cylinder and then observed the behaviour of the second rat in the cage. This second rat was stubbornly determined to liberate the first rat and had to overcome great fears and difficulties to do so. This simple experiment captures the main idea of the lecture: the ability to act altruistically is not uniquely human, as has often been slightly arrogantly proposed by philosophers like Dennett.  Even mammals that are traditionally seen as selfish are surprisingly capable of showing empathy and morality, since these traits are locked in mammal brains. It’s mostly nature, not nurture.

Neocortices and neurotransmitters

A key milestone in our evolution from being self-absorbed reptiles to caring and social mammals is the development of the neocortex, which is the part of our brain that is incredibly flexible and adapts to our environment. This gives mammals a significant advantage over their reptile neighbours. However, having a neocortex does come with one crucial flaw: although the neocortex is a master at expanding and tuning itself to its surroundings, it does not amount to much at the beginning of a mammal’s lifetime. The neocortex of a young mammal is rather immature, which, in consequence, means that these babies are incredibly dependent on their mothers. The mother-baby bond, which lies at the base of sociality, was born at this turning point.

The hormone and neurotransmitter oxytocin is another important biological aspect of why we, by nature selfish, can feel such a strong bond with other beings that we are willing to risk our own wellbeing for theirs. This hormone, which is released during any kind of social interaction, reduces stress levels and blood sugar, but also makes you more likely to feel connected to others and to understand social signals.

In Darwin’s footsteps

By presenting these hefty biological topics as the neuroscientific beef-up of Charles Darwin’s theory on morality, Patricia Churchland placed these topics in a historical context and managed to give a talk that touched on many fields, but that was admirably unified.


This lecture was organised by the Honours Academy and hosted in the Academy Building. In the crowded auditorium honours students, honours affiliated staff members, but also the broader audience of Leiden University’s academic community, attended the first Honours Academy lecture. This lecture was the opening of an Honours Academy lecture series. The theme of this series is Identity and the next lectures (in the second semester) will be announced in due time on the Honours Academy website.

Zaza Jung, student Pre-University College

Last Modified: 27-10-2015