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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.

Explainer

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Economics

Leading

Politics

Wisdom

8 May 2025

5 min read

When someone makes a claim, ask yourself these questions

How stories, statistics, and studies exploit our biases.

Alex Edmans

Alex is a professor of finance, and an expert in the use and misuse of data and evidence.

A member of an audience makes a point while gesturing.

On the other hand...

Antenna on Unsplash.

“Check the facts.”

“Examine the evidence.”

“Correlation is not causation.”

We’ve heard these phrases enough times that they should be in our DNA. If true, misinformation would never get out of the starting block. But countless examples abound of misinformation spreading like wildfire.

This is because our internal, often subconscious, biases cause us to accept incorrect statements at face value. Nobel Laureate Daniel Kahneman refers to our rational, slow thought process – which has mastered the above three phrases – as System 2, and our impulsive, fast thought process – distorted by our biases – as System 1. In the cold light of day, we know that we shouldn’t take claims at face value, but when our System 1 is in overdrive, the red mist of anger clouds our vision.

Confirmation bias

One culprit is confirmation bias – the temptation to accept evidence uncritically if it confirms what we’d like to be true, and to reject a claim out of hand if it clashes with our worldview. Importantly, these biases can be subtle; they’re not limited to topics such as immigration or gun control where emotions run high. It’s widely claimed that breastfeeding increases child IQ, even though correlation is not causation because parental factors drive both. But, because many of us would trust natural breastmilk over the artificial formula of a giant corporation, we lap this claim up.

Confirmation bias is hard to shake. In a study, three neuroscientists took students with liberal political views and hooked them up to a functional magnetic resonance imaging scanner. The researchers read out statements the participants previously said they agreed with, then gave contradictory evidence and measured the students’ brain activity. There was no effect when non-political claims were challenged, but countering political positions triggered their amygdala. That’s the same part of the brain that’s activated when a tiger attacks you, inducing a ‘fight-or-flight’ response. The amygdala drives our System 1, and drowns out the prefrontal cortex which operates our System 2.

Confirmation bias looms large for issues where we have a pre-existing opinion. But for many topics, we have no prior view. If there’s nothing to confirm, there’s no confirmation bias, so we’d hope we can approach these issues with a clear head.

Black-and-white thinking

Unfortunately, another bias can kick in: black-and-white thinking. This bias means that we view the world in binary terms. Something is either always good or always bad, with no shades of grey.

To pen a bestseller, Atkins didn’t need to be right. He just needed to be extreme.

The bestselling weight-loss book in history, Dr Atkins’ New Diet Revolution, benefited from this bias. Before Atkins, people may not have had strong views on whether carbs were good or bad. But as long as they think it has to be one or the other, with no middle ground, they’ll latch onto a one-way recommendation. That’s what the Atkins diet did. It had one rule: Avoid all carbs. Not just refined sugar, not just simple carbs, but all carbs. You can decide whether to eat something by looking at the “Carbohydrate” line on the nutrition label, without worrying whether the carbs are complex or simple, natural or processed. This simple rule played into black-and-white thinking and made it easy to follow.

To pen a bestseller, Atkins didn’t need to be right. He just needed to be extreme.

Overcoming Our biases

So, what do we do about it? The first step is to recognize our own biases. If a statement sparks our emotions and we’re raring to share or trash it, or if it’s extreme and gives a one-size-fit-all prescription, we need to proceed with caution.

The second step is to ask questions, particularly if it’s a claim we’re eager to accept. One is to “consider the opposite”. If a study had reached the opposite conclusion, what holes would you poke in it? Then, ask yourself whether these concerns still apply even though it gives you the results you want.

Take the plethora of studies claiming that sustainability improves company performance. What if a paper had found that sustainability worsens performance? Sustainability supporters would throw up a host of objections. First, how did the researchers actually measure sustainability? Was it a company’s sustainability claims rather than its actual delivery? Second, how large a sample did they analyse? If it was a handful of firms over just one year, the underperformance could be due to randomness; there’s not enough data to draw strong conclusions. Third, is it causation or just correlation? Perhaps high sustainability doesn’t cause low performance, but something else, such as heavy regulation, drives both. Now that you’ve opened your eyes to potential problems, ask yourselves if they plague the study you’re eager to trumpet.

A second question is to “consider the authors”. Think about who wrote the study and what their incentives are to make the claim that they did. Many reports are produced by organizations whose goal is advocacy rather than scientific inquiry. Ask “would the authors have published the paper if it had found the opposite result?” — if not, they may have cherry-picked their data or methodology.

In addition to bias, another key attribute is the authors’ expertise in conducting scientific research. Leading CEOs and investors have substantial experience, and there’s nobody more qualified to write an account of the companies they’ve run or the investments they’ve made. However, some move beyond telling war stories to proclaiming a universal set of rules for success – but without scientific research we don’t know whether these principles work in general. A simple question is “If the same study was written by the same authors, with the same credentials, but found the opposite results, would you still believe it?”

Today, anyone can make a claim, start a conspiracy theory or post a statistic. If people want it to be true it will go viral. But we have the tools to combat it. We know how to show discernment, ask questions and conduct due diligence if we don’t like a finding. The trick is to tame our biases and exercise the same scrutiny when we see something we’re raring to accept.

This article is adapted from May Contain Lies: How Stories, Statistics, and Studies Exploit Our Biases – and What We Can Do About It
(Penguin Random House, 2024)
Reproduced by kind permission of the author.

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