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Awe and wonder

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7 September 2023

6 min read

The heart of the matter

Heart doctor Michael Henein steps back to consider the unseen and unique wonders of the human body’s design.

Michael Henein

Professor Michael Henein is a consultant cardiologist, and a Professor of Cardiology at Umea University, Sweden.

A model of a human heart on a short stand.

Photo by Jesse Orrico on Unsplash.

Shakespeare famously asked:

“What a piece of work is a man, how noble in reason, how
infinite in faculties, in form and moving how express and admirable, in action how like an angel, in apprehension how like a god! the beauty of the world, the paragon of animals—and yet, to me, what is this quintessence of dust?

Humans may be complex, capable of great heroism and deep depravity, yet it is worth stopping for a moment to look at the human body and mind to marvel in what we have become, and how we are made.

The visible design of the human body points out common features shared along with other members of the animal kingdom. Examples of these features are: two eyes, two ears, two nostrils, one mouth and four limbs, attached to a body and head. Detailed study of different seen parts of the body may, however, show some differences. For example, the presence of fingers and nails, hair distribution as well as a developed tail. While most members of the animal kingdom have teeth and a tongue, those two could also vary in their number and size, respectively, according to different species. Genetic investigations have shown that we humans share 99 % of our genes with animals, suggesting that our “earthly” component shares a common origin. Indeed, the twenty first century scientific findings match what is written in the Genesis story of creation, a story written over 3,500 years ago, well before genetic sciences came to light.

Creatures great and small

As for morphological differences between animal species, it is difficult to naively conclude why some are wild while others are man-friendly-even if the wild ones have different shapes, design, dietary habits, body size and life span. Other important observed features of the members of the animal kingdom are that they are all born, they all age, then ultimately die.

If we are to look at the unseen features of the members of the animal kingdom, we can again identify similarities. For example, all have a gastrointestinal tract, a cardiovascular system, a reproductive system, a respiratory system, a urinary system and much more. While these systems may differ slightly between species, the overall structure and function achieve similar purposes. For example, heart speed is faster in small animals like rats compared to big ones like elephants who have very slow hearts. Likewise, the respiratory system and the number of respiratory cycles per minute are significantly faster in running animals compared to the sedentary and slowly moving ones. Finally, the number of offspring also differs in different species, being just one at a time in big animals like elephants and horses, and many offspring in small animals like rabbits and mice. Such paradox between the number of offspring and animal size makes you think of the important determining role of the activity of those animals.

Unseen wonders

Now to turn to the rest of the animal kingdom and the unseen features of the human body. To start, let us look at the amazing functions of the human brain and its various functions. When humanity is sometimes described as the crown of creation, such a description is based on the superiority of human brain function and skills. Its sophisticated structure and how vital centres are created deep in the skull, to be protected from traumas, make you marvel. Also, the brain controls the different functions of the whole body, with its sensory and motor activities, various vital system functions including the lungs and the heart, all endocrine glands’ function, in addition to various receptors and centres that allow utmost precision and accuracy in everything we do. An example of this kind of precision is a doctor feeling a vein or an artery with the tip of a finger to insert a needle or a musician moving a finger a few millimetres while playing a violin, to produce the exact sound needed. Furthermore, the integrated function of human muscles, nerves and spinal cord is also amazing, let alone the synapsis between the nerve endings and muscle bundles, the chemicals secreted in them which allow electric stimulus transmission from the nervous system to achieve the motor function and desired movement.

The human brain also has the unique feature of storing knowledge. Of course, we should not ignore the importance of the training and programming ability of human brain. We learn how to drive a car, how to play games, how to study, how to operate safely on a sick patient. Such acquired skills are quite limited in other members of the animal kingdom. Moreover, the human brain has the unique ability to invent, discover, improve and correct errors it identifies.

Another very unique feature of human brain is its ability to conduct speech, a feature of humans that is under-developed in other members of the animal kingdom. While most animals can make noise and sounds, only humans can articulate words, sentences and even sing very complex songs. This unique ability seems to be the underlying mechanism behind the development of languages which are based on the human ability to talk and transmit information and knowledge by words and phrases.

The unseen brain has allowed human life to develop over time, building skills and achievements from generation to generation. Millennia ago, humans lived in huts together with animals, and now they build houses and palaces to live in. Centuries ago, we used donkeys, horses and camels to travel but now we use cars, trains, ships and airplanes. Our ancestors burned wood and coal to cook and to warm but now we use electricity to do these.

When we look carefully at the unseen parts of the human body, we also realize that we cannot alter any of it, despite the scientific advances made over the years. We can understand what harms our body and take measures to avoid it. Out of the ability of our brain to discover and invent, we have now produced science-based means for curing various diseases. Consider how we can replace a dysfunctional heart valve or a mobility-limiting joint. These inventions have resulted in a better quality of life, alleviating of symptoms, even helping to avoid early death, in some cases such as heart disease and cancer.

The heart of the matter

Another unseen source of life in humans is the heart. This fist-size organ is so complex in its structure and function. Recent scientific advances have enabled us to study heart function in milliseconds, hence the development of pacemaker treatments. They have also allowed clear imaging of the inside of the heart and the identification of pathologies, developments that guide practitioners to the optimum treatment of heart conditions. Recent discoveries have also allowed us to better understand how people develop coronary artery disease and how the pathology starts at the innermost layer of the arteries, particularly in individuals carrying significant risks for atherosclerosis including, smoking, high blood pressure, diabetes, high cholesterol and obesity. Amazingly, obesity has been shown to be the strongest underlying cause of other risk factors, hypertension, diabetes and hypercholesterolemia. So, nature cannot be blamed in many of these patients but our own patterns of behaviour. Science has shown that walking at least 5,000 steps each day, complying with the design of our body, reduces the likelihood of developing coronary artery disease by 15 per cent.

The unseen physiology of the rest of our body systems and the interaction between systems make us wonder how we are made. A rise of our body temperature by one degree due to a bug infection affects all body systems from the brain to the heart. A virus which cannot be seen by the most powerful microscope can destroy our lungs and cause premature death, as was the case with COVID-19 and others.

Finally, human inventions in the form of powerful microscopes have allowed scientists to study the human cell, which is the smallest living component of our body. Such small cells cannot be replicated in any factory in the twenty-first century, despite the vast scientific developments that surround us. You'll be surprised to learn how complicated and meticulously fine-tuned a human cell is and also how it functions, connects with other cells and other parts of the body. An example of this is the interaction between body minerals, calcium, sodium and potassium with heart and muscle individual cells. Such a function is critically controlled by many factors such as time, electric stimulation and pressure differences producing remarkably harmonious contractions and relaxation of the muscles without missing a beat.

Essay

Awe and wonder

Creed

Easter

21 March 2025

7 min read

At the tilting points of the year, we ask what kind of world we want to build

Equinox is still a threshold between darkness and light.

Elizabeth Wainwright

Elizabeth Wainwright is a writer, coach and walking guide. She's a former district councillor and has a background in international development.

Sun rise casts a shadow over Stonehenge.

Nik, via Unsplash.

At the spring equinox, we appreciate and talk about the arrival of light in the northern hemisphere. For a brief moment, the Earth’s axis is tilted neither away from or toward the sun, and day and night are roughly equal length – ‘equinox’ is Latin for ‘equal night’. From here, we enter astronomical spring.

But it is not entirely accurate to talk about this being the moment when the darkness is finally diminished. That moment is the ‘equilux’ – equal light – and it happens a few days before the equinox, its date varying with latitude. Because the sun appears as a disc in the sky, the top half rises above the horizon before its centre does, which – when coupled with light being refracted by the Earth’s atmosphere – gives extra daylight. By the time of the equinox, and depending on your latitude, we already have 12 hours and 10 minutes of daylight. It is not much, but it is enough perhaps to read a few pages of a book without an artificial light, or to have “just one more” kick of a ball outside, as my daughter has learned to say.

There is beauty in the idea that for a brief moment during the equinox, we are all experiencing the same light and dark. But it is not true. At any particular moment, some of us experience more darkness than others, and some of us receive more light than we think.

Whenever its moment of arrival, though, the light will arrive. It always has, since the world was set spinning and tilting in space. We have always found ourselves poised at the threshold between the long dark of winter and the gathering light of summer. It is a threshold that is embedded in creation itself; all of life must in one way or another face the work, the inevitability, the challenge of transformation. This threshold is echoed through our own lives too – in the in-between spaces where one thing is ending, but the next has not yet fully begun. There are personal thresholds: a change in career, a birth, a loss. And there are collective ones: times in history when the old ways no longer work and we strain toward something new, unsure of how to get there.

Ancient people marked the equinox with purpose and care, watching for the moment the sun rose in the east and set in the west. At places like Stonehenge, huge stones were arranged to capture the exact angle of equinoctial light, as if the builders knew this threshold was something worth marking. Recently, archaeologists have suggested that Stonehenge was built not just for religious reasons, but for unification too: its stones come from Cornwall and Wales and Scotland – from all parts of the land. Their slow journey to their resting site on Salisbury plain would have been a chance for celebration and feasting, with thousands of people joining in along the way. It was a journey that would have brought together different people, including groups that had migrated from modern day Europe. Gathering light was a shared effort, and one worth celebrating.

For the early Celtic world, the equinox was a hinge between Imbolc, the season of early stirrings, and Beltane, the riot of summer. It was a time for reckoning and renewal – counting what food remained after winter, deciding what animals to keep or cull, what seeds to plant. To live well meant paying attention to the balance between what had been and what was to come. Lately, I have realised that it is not change itself that feels hard so much as not knowing the nature of the change that I, that we, will be called to. My young daughter has brought this into sharp focus. On the days when the dark feels relentless and the light seems distant, I find myself fearing for her future. I think of those Celtic people; the way they did not know the future but prepared for it anyway, perhaps in their rituals asking, how do the past and the future speak to each other at this moment, who are we, who might we become?

Even if we long to cling to what is familiar, the familiar will eventually change. Easter, and the equinox, are not just about light triumphing over darkness, but about transformation.

In a world where crisis seems to be following crisis, it is easy to feel that everything is tipping off balance. The equinox suggests though that equilibrium has never been static, and balance has only ever been fleeting, a transition between states of being. It is a moment of poised readiness, a preparation for movement. The world will keep tilting and tipping as it always has, and we will keep changing as we always have.

In the Jewish calendar, the equinox often falls near Passover, the great festival of liberation. The story of the Exodus is a story of transition – of leaving behind what enslaves us even when the road ahead is unknown. The Israelites did not step from captivity into freedom overnight. They wandered, and wrestled with doubt, and longed for the certainty of their old lives even as they were being offered something new. Thresholds are rarely comfortable.

I find myself at a threshold now: I am trying to shape a life that has reformed around motherhood, with past roles and jobs behind me, and the new identities yet to fully clarify. I have been feeling the truth of farmer-author Wendell Berry’s idea that "it may be that when we no longer know what to do, we have come to our real work." This real work has been stimulating but also confronting, as thresholds often are.

If we are, as many believe, living through a threshold moment in history – where old systems are failing, where climate and conflict threaten the future – how do we walk forward? How do we resist the temptation to cling to what is familiar, even when it no longer serves us? Easter falls just after the equinox. Shoots push through soil, lambs stumble into life, a chorus of birdsong swells, and we remember that nature is all resurrection. Even if we long to cling to what is familiar, the familiar will eventually change. Easter, and the equinox, are not just about light triumphing over darkness, but about transformation. Jesus did not return from the tomb unchanged; he was made new, unrecognisable at first, even to his closest friends.

The balance of light and dark is fleeting; it does not last; a threshold is not a place to linger. The world is always moving towards light, or toward dark, but always through change, and so are we. Balance is not an end in itself; it is a preparation for change. Perhaps these tilting points of the year are good moments to ask who we are becoming, and what kind of world we want to build, and how we will bear witness to the light, but also to the dark, as we do so.

This equinox, then, we will turn and face the coming light, but perhaps too we might turn and notice the faces that the light shines on – or doesn’t. Virginia Woolf reminds us that "A light here required a shadow there." When the light comes, darkness will too. These turning points of the year are an opportunity to sit in the truth of that, to appreciate the hope and the beauty of this spring threshold, but also to get to work. We can reach out to those who are experiencing more darkness than us, help build the world in such a way that draws attention to the light like the makers of Stonehenge did, take stock of what has been and who we are becoming, step away from what enslaves us even if we are not yet sure of the shape of freedom.

We cannot know what will happen next, but we can choose how to move forward. I wonder about those ancient people who somehow moved huge stones weighing up to 30 tons to Stonehenge; I wonder what they saw as they moved through the land, when they looked to the horizon, when they stood in the tension of their own now. They carried not just the weight of stone, but of their own unknowable future. Those ancient people persisted and celebrated and became us, passing on their burden, passing on their particular stone-bound, collectively built way of focusing the light. This equinox, I am thinking about how I can do the same – despite and because of the darkness, despite and because of the unknown path ahead.

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