So, are we animals? For many people today that sounds like a silly question. Of course, humans are animals!
We’re composed of cells with genetic material, and we move around, seeking energy to feed our bodies, pooping it out again as waste. We look a lot like our fellow primates with our five-digit hands and feet, our thoughtful eyes, and our lean, muscular physiques. We have lungs, a heart, a brain, a nervous system, and all those other features we share with mammals.
And just think of the “nodal” (the protein encoded by the NODAL gene), important to early embryonic development and crucial to our interior asymmetry. A decade ago, scientists discovered that this same signalling molecule gifts the humble snail the lopsided coil of its shell. A reminder, if we still need one, that all life is our kin.
So why have we spent much of modern history arguing to the contrary? And why does the idea that, somehow, we’re not really animals continue to grip our imaginations?
In classical thought, it was assumed that all life had a soul of some sort. But souls were still ranked in order of quality. Humans were thought to possess a better kind of soul in a hierarchy, with only the angels and God above us. And these intuitions took a new turn with the rise of scientific rationalism during the Enlightenment.
Humanists argued that we are separated from all other life through our exceptional minds, capable of moral thought and free will. It was even suggested that we are our thoughts and that these soul-like mental aspects of humans are more important and somehow separate to our bodies. That legacy of thought has proven extremely difficult to shake.
Theologians, philosophers, jurists, even scientists continue to claim that, while we may appear to be animals in many ways, being “human” is something different, something special or even non-biological.
The trouble for us is that this downplays all that is precious and valuable about our physical, animal life, from the games between children to the joy we experience when someone smiles.
And, as humans, different rules apply to us. We are allowed to monopolise the Earth’s resources and use other species for our own ends not because we’re animals but because we are beings with special, unique properties. Unless we confront that worldview, it will be remarkably difficult to put the stopper on our destructiveness.
Are human minds different from animal minds?
If you listen only to some cognitive scientists and technologists, you might think that our minds are like a mathematical formula that we will soon be able to lift out of our animal bodies and download into a human simulation, like a robot body or computer.
More recently, some neuroscientists have argued that to understand the mind, we need only consider the brain. As philosopher Derek Parfit put it, “the body below the neck is not an essential part of us.” But recent work has cast such a view in doubt.
The mental world of a human being – what we might call our human “experience” – is intimately affected by everything from our gut bacteria to the state of our various limbs. Studies on organ transplant patients have found that an alien organ disrupts everything from hormone release to the firing of neurons, which then influence identity, mental experience and mood.
The question, then, is whether we think that what matters about thought is purely goal-directed, computational thinking – ie. algorithmic, information-processing – or also our affective states – our experience of thoughts and memories as triggers for feeling states and emotions.
Indeed, do we think that these emotional “worlds” actually matter more when we consider what it means to be human? If that is the case, our hormonally-charged, physical being is far more important than we’ve acknowledged. And that is significant as we develop more and more technologies that disrupt or alter our bodies, from the use of our smartphones to more invasive possibilities like the brain-machine interfaces showcased by Elon Musk in 2020.
Gertrude the pig, who has a Neuralink brain-machine interface connected to neurons in her snout © Neuralink
And how we think about the value of animal being has huge consequences for how we come to think about the lives of other species too. Today, much of our legal language states that only human experiences have full moral value. You might even come up against the idea that other animals don’t really have minds or experiences in any meaningful way.
But these kinds of ideas are also looking increasingly unconvincing. In 2012, a series of leading scientists published the Cambridge Declaration on Consciousness, in which they claimed that consciousness of some imaginable kind is likely to be widespread, especially among mammals, birds, and cephalopods.
Some have argued back that the absence of humanlike subjectivity strictly limits what these experiences might be. Yet feeling and intelligence are profoundly useful defensive and expressive properties of biological beings. It’s parsimonious to assume evolution has called for them again and again throughout the long reach of time.
And, as neuroscientist Randolf Menzel has since argued, no brain is “structurally simple”. Menzel studies insect brains and reminds us that the honeybee has around 960,000 neurons within a hive of 50,000 or so cooperating individuals.
And it’s not just a matter of counting neurons. Some species have more neurons in their forebrains, like dogs and long-finned pilot whales – species that are highly social animals. The more we learn, the more we realise that life on Earth is full of diverse forms of intelligence and purpose.
As we stand on the brink of a biodiversity crisis and increasingly technologised lives, it’s time for us to rethink not only what’s precious to us about our animal life but to recognise that we don’t have the monopoly on valuable lived experiences. A little more humility would serve our species well if we want to be better prepared, both morally and mentally, for the future.
Are humans animals? | BBC Science Focus Magazine
Do humans have animal bodies – and animal minds?
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