Neurophilosopher argues morality is rooted in brain science, not reason

How do we determine right from wrong? According to Patricia Churchland, the answer is through science and philosophy. The distinguished proponent of neurophilosophy explores how moral systems arise from the influences of nature and nurture in her book, Conscience: The Origins of Moral Intuition.

Patricia Churchland explains the origins of conscience evolved in our mammalian ancestors

Patricia Churchland, a renowned proponent of neurophilosophy, explores how moral systems arise from the influences of nature and nurture in her book, Conscience: The Origins of Moral Intuition. (Becky Cohen/W. W. Norton & Company)
Listen to the full episode53:59

Telling right from wrong, or deciding how to feel about other people's behaviour, is a job for our consciences.

But where does that voice of conscience come from? And why should we trust it?

As Leonard Cohen once sang, "I don't trust my inner feelings. Inner feelings come and go." The famed Montrealer was reiterating a point made by Socrates right at the beginnings of Western philosophy. The inner voice can mislead us.

For Patricia Churchland, professor emerita in philosophy at University of California San Diego, it's instructive to know more about the origins of our human consciences. She argues the starting point could be as early as the first warm-blooded animals more than 200 million years ago. 

What began as an adaptation to foraging in cold or nighttime environments spurred further adaptations, such as a propensity to nurture, socialize, and learn from others.

Brain structures encouraging social behaviour took mammals right up to the doorstep of what we call morality in humans.

"I don't think that human behaviour is different in kind from the behaviour we see in chimpanzees, or baboons, or wolves," Churchland told IDEAS host Nahlah Ayed.

"I think it is more complicated because our ecology — especially now — is more complicated."

Vole brain breakthrough

Churchland wants the scientific research to inform what has long been a philosophical or religious conversation. Often, thinkers tried to answer questions such as "Why be good?" with appeals to reason or divine authority.

The biological story offers us a different answer: brain wiring.

"Why is [being social] so meaningful? Why do we care? We care because we're like that," said Churchland, author of Conscience: The Origins of Moral Intuition.

Prairie voles mate and bond for life, says Churchland. (Submitted by Emory University)

The philosopher explains that a key discovery for her came from research into vole biology.

A difference in the number and location of oxytocin receptors in the brains to two vole species — one adapted to life in mountain ecosystems, and the other to life on the plains — appeared to regulate the voles' love lives. 

The prairie voles, with more oxytocin receptors in certain areas, mated and stayed together to raise offspring. They show signs of emotionally depending on their partners, and acting altruistically for the good of the other.

This link between a physical adaptation to an environment and certain behavioural or cultural dispositions, such as caring for others rather than just the self, seemed to justify a biological basis for what we call moral behaviour.

Churchland insists that rooting morality in brain science, rather than reason or divine justice, does not diminish the value of our moral aims. 

"No, I think these rather humbling things are so charming and they make us feel our biology in this wonderful, warm way!" she said.

"I think it's great." 

* This episode was produced by Tom Howell.


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