The question, “Show me the facts” is sometimes asked to evaluate an idea. Although the question appears reasonable, closer analysis indicates its reasonableness can be superficial.
Every day of my life, when the sky is not fully overcast, I see the sun rise in the east, climb to a zenith and then descend towards the horizon where it sets in the west. I have made this observation in arctic Norway, at Cape Agulhas in South Africa, on the coast of British Columbia and in Hong Kong. I have made this observation at all times of the year throughout all my life. I have never seen an exception to this observation and when I discuss it with other people, I invariably learn that they have seen the same thing. I have read that the Ancient Greeks, Ancient Egyptians, Arabs in the Middle Ages, Babylonians and Mayans used their observations of the Sun’s path around the Earth to calculate accurately the Sun’s position in the sky for every hour of the day during every day of the year. I have also learned that modern astronomers calculate the Sun’s future position from past observations of its path around the Earth. It is reasonable to accept the geocentric theory that the Sun orbits the Earth, as it correlates with my experience, with other people’s experience, with precise scientific observation and with astronomical calculations. Then I read in books that modern astronomers have rejected the geocentric theory and accepted the heliocentric theory that the Earth orbits the Sun. Both ideas are theories, because they explain the facts. No one has ever observed the Sun going round the Earth or the Earth going round the Sun.
Why do educated people accept the heliocentric theory, even though it contradicts what they observe every day? According to astronomers, the geocentric theory cannot explain the following groups of observations, while the heliocentric theory can explain them:
The phases of Venus. The Moon reflects the Sun’s light onto Earth. During a lunar month the Moon’s position relative to the Sun and to the Earth changes, which causes the Moon to exhibit phases – New, Gibbous, Full and Gibbous again. Like the Moon, Venus reflects sunlight onto the Earth. As Venus and Earth both orbit the Sun, the position of Venus relative to the Sun and to the Earth changes, which causes Venus to exhibit phases like the Moon;
The periodic retrograde motion of planets. Planets usually move westward across the sky from one night to the next. Periodically planets, however, appear to do a backwards loop and head eastward. in the Earth’s sky. This is known as retrograde motion. Planets orbit the Sun at different speeds. Mercury and Venus, being closer to the Sun orbit faster than Earth does, while Mars, Jupiter, Saturn, Uranus and Neptune, being further from the Sun, orbit more slowly than Earth does. When Venus or Mercury overtakes Earth, it appears to do a backwards loop in Earth’s sky. When Earth overtakes Mars, Jupiter, Saturn, Uranus or Neptune, the planet appears to do a backwards loop in Earth’s sky;
Stellar parallax. During the course of its annual orbit round the Sun, the Earth changes its position by 300 million kilometres. This change is enough for a star that is close to the Earth to appear to move relative to stars that are further away from Earth. We see this effect when we drive past buildings. Seen from our car, buildings change their position from being ahead of us to being behind us. Distant buildings do not change their position as much as near-by buildings, near-by buildings appear to move relative to distant buildings. This effect is known as parallax. As the Earth obits the Sun, stars that are near to Earth appear to change position relative to stars that are distant from Earth. In 1838 Friedrich Bessel used the parallax of 61 Cygni to estimate the distance between the Sun and 61 Cygni;
Stellar aberration. A star can appear to move slightly in the sky from day to day. In 1727 James Bradley suggested that this phenomenon was due to variations in the Earth’s speed as it orbits the Sun. In the 20th century Einstein’s theory of special relativity adjusted Bradley’s mathematics without changing his basic explanation.
How many people, who accept the heliocentric theory, could list these four observations? Few of those people, including myself, have actually made any of these observations for themselves. Large numbers of people accept the heliocentric theory, because of hearsay. This raises an important question, “Why do we accept one idea and reject another when we have not observed any of the relevant facts for ourselves?” This question is particularly pertinent when the idea appears to contradict our personal experience, as is with the Sun’s daily movement across the sky.
Surveys of the reasons why people voted to leave the EU in the Brexit referendum indicate that voters accepted the message on the Vote Leave Bus that leaving the EU would give the UK Government an additional £350 million to spend on the NHS per week. The same voters, however, rejected statements by economists, the Governor of the Bank of England and the Managing Director of the IMF that leaving the EU would cause Britain to be poorer.
Why do we accept some statements and reject others? In many criminal trials witnesses give contradictory testimonies. Some testimonies imply guilt and others imply innocence. Some witnesses are lying, while others are telling the truth. The jury has to decide what is true and what is false. How does a jury answer Pilate’s famous question, “What is truth?”
The internet has made more information more easily available to more people than in the past. If everyone applied the rules of logic to the same data, they would reach the same conclusions. In the age of the internet, however, opinions seem to be diverging more than converging. People do not appear to reach conclusions by the application of logic to data.
Do our opinions simply reflect the consensus of the group to which we belong? Many cyclists think some motorists are road thugs, who treat cyclist as roadkill on wheels. Many motorists, however, dislike cyclists, because they ride two abreast, disregard the highway code and slow down traffic. Cyclists and Motorists often reflect the attitudes of the group to which they belong. Both groups are of course right and wrong. Some cyclists do disregard the rules of the road and some motorists do drive dangerously close to cyclists. Other cyclists and motorists behave properly.
In the Trumpine era of fake news and alternative facts, it is more important than ever that we are able to assess the veracity of information. How do we do this?
I admit it. I enjoy reading the Economist. I find it insightful and on occasions amusing. I also realise that the Economist has a very definite world view. It believes in free markets, the decriminalisation of drugs, and an open society, in which information is shared. It has strong antipathy for President Trump and for Brexit. I believed that as long as I understood its world view and position on issues, I could read the Economist without having my views shaped by it. Then I read an article, in which the Economist polled its staff for the worst international airports. The results of the poll agreed with my selections for the worst two international airports. Nether airport is well known. Neither is Changi, JFK, O’Hare, Heathrow, Gatwick, Schiphol, Charles de Gaulle, Dulles or Frankfurt. The result of the poll deeply concerned me. Is my mindset so shaped by the Economist that we even agree about airports? Is my world view that of the Economist? Are my tools for testing the veracity of facts, tainted by that weekly? I sometimes wanted to scream at right wing Americans, “There are other news sources than Fox News”. Perhaps they could have screamed at me, “There are other news sources than the Economist”.
Being human, we have emotions, prejudices and preconceptions. All of them influence our interpretation of the world around us. We are not purely rational animals. We do not always act in our own best interests. We make mistakes.
A democracy assumes that the people will not elect a criminal to leadership. What happens when the people make a mistake? When that happens, a potential conflict arises between the democratic vote and the rule of law? People seem to choose sides based on political affiliation rather than evidence. In Nazi Germany the population continued to believe and trust Hitler, even as the evidence for his wrong-doing mounted. The Anglo-Saxon nations looked at Nazi Germany in the belief that such a thing could never happen in their countries. Were they correct? A frog can be boiled alive by raising the temperature of the water, in which it is swimming comfortably, by one degree at a time. We can lose our democracy by one tiny event at a time. How do we know what is true, when so many of our opinions are based on hearsay? How can we judge properly?
With so many opinions pointing in so many different directions, it is more important than ever to listen openly to a wide range of opinions. Yet it is so easy to tune into just Fox News or just CNN to evaluate Donald Trump, or indeed to listen to Theresa May on Labour’s antisemitism or to Jeremy Corbyn on Tory antiafrocaribbeanism. I just wish politicians would recognise that ordinary people are at the sharp end of their politics, whether they be African Americans and Mexicans in the USA, or Jews and West Indians in the UK.