The underlying realities of the world – from Earth’s rotation around the sun to Darwin’s theory of evolution – are rarely obvious or expected
The horizon
The horizon tells us the Earth is flat but our perception is often wrong.
Photograph: Alamy
All is not what it seems. Much of the universe – from the unimaginably small to the cosmological – is not how it appears to us, and our view is lamentably limited. The Earth’s rotation around the sun has been accepted for less time than it was not, and we still don’t yet know what makes up most of the cosmos. The knowledge that all life is built of cells is less than two centuries old, that all life is encoded in DNA has been known for just 50 years. When Darwin came up with evolution by natural selection, his loyal ally TH Huxley exclaimed “How extremely stupid, not to have thought of that!”

But evolution is not obvious at all, and it took thought and experiment and hard tenacious graft to reveal that truth. The real structure of the universe – the atomic, subatomic and quantum – was concealed from our eyes for all but the tiniest fragment of our tenure on Earth. We humans are awful at perceiving objective reality. We come with inbuilt preconceptions and prejudices. We’re dreadful at logic, and see patterns in things that are not there, and skip over trends that are. We attribute cause and agency to chance and coincidence, and blame the innocent as the root of all manner of evil. We use the phrase “common sense” as an admirable quality for scrutinising the world in front of us.

If this all sounds misanthropic, it’s not. Blind, directionless evolution gave us the gumption and the tools to frown at what we see, and ask if it really is how things are. Science is quite the opposite of common sense.
Common sense deceives us all the time: the horizon tells me the Earth is flat; people seem to get better after taking homeopathic pills; spiders are dangerous; a cold snap ridicules global warming. Of course, it is tricky to challenge someone’s opinion successfully if it is based on their learned experience. But that is exactly what science is for. It is to extract human flaws from reality; it is to set aside the bias that we lug around. Our senses and psychology perceive the world in very particular ways that are comically easy to fool. But the great strength of science is that it recognises the human fallibility that cripples our view of the universe. The scientific method attempts to remove these weaknesses.
 
 

That is why this should be instilled in us from as early as possible. At school, the facts must be taught, and the histories of those discoveries too. But we must bequeath the next generations the tools to question our limited perception – science as a way of knowing. It is frequently said – often by people like me – that children are born scientists, that their curiosity is inbuilt, and that this is eroded by age. It’s a pleasant sentiment, and certainly children are unsullied by the baggage of a life.

But children are not scientists. As ever, anything of value comes with effort, not by grace. Science is a particular way of thinking, not beset but enabled by doubt, and it comes from teaching. Somewhere in the country there is an eight-year-old girl who will change the world and win a Nobel prize for it. She will make people healthier, or see new stars, or merely reveal wonder. But it will be because her parents and teachers have taught her not to be satisfied with how things appear, and given her the tools to think critically and force the universe to reveal its true nature.
I was prompted to write this after I wrote on the biological non-existence of “race” a few weeks ago, and this prompted ire (and plenty of charmless racial abuse). Much of the commentariat was expressing the view that “obviously race exists because people look different, and these differences broadly cluster into traditional descriptions of race – blacks, whites, Asians”.

Modern genetics has unearthed a treasure trove of information about humans that was previously veiled or indecipherable, one of which is that some sets of genetic signatures broadly correlate with large land masses, especially ones bound by oceans. But these are neither exclusive nor essential associations with the way we use the term “race”. Last month, in the journal Nature, genetics was used to question, support and in some examples refute the history of the British people. The study catalogued the major immigrations from mainland Europe up until the 10th century, as revealed by subtle shadows of these interlopers hidden deep in our DNA. Guardian columnist Simon Jenkins opined that some of the results were “simply implausible” because the study was “strong on algorithms but weak on archaeology”. Well, evidence of all sorts is used to piece together the past, and one is not better than the other. But the algorithms used by geneticists are not there for fun, or to befuddle, but to reveal patterns that are otherwise invisible. Indeed, the scientific techniques are routinely used on actual physical artefacts to expose what is hidden. What I can say with utter confidence is that as we continue to explore and characterise the human condition, we’ll find more things that may feel untrue or implausible or uncomfortable. Maybe now is the time to get on board with uncertainty, discomfort and novelty.