Why do giraffes have long necks? To reach tasty leaves high up in the African Savannah, of course. That explanation neatly fits the theory of evolution. Yet it can’t really be that, since their main food is ground level bushes, tidy though it would be.
Nevertheless, plausible misinformation like this is regularly passed down to each generation as part of our efforts to explain everything. The humble giraffe’s neck illustrates an important truth, which is that the greatest error of them all is to confuse fact with theory, certainty with supposition.
Actually, moving on from what giraffes eat, our own food fads are a good place to see “science” giving spurious authority to dodgy theories, not to say commercial interests. Take, for example, the idea that “fat is bad”. This can be traced back to a single researcher, called Ancel Keys, who published a paper in the 1950s saying that Americans were suffering from “an epidemic” of heart disease because their diet was more fatty than their bodies were used to after thousands of years of evolution. A survey demonstrating that a high-fat diet coincided with high rates of heart disease excluded the bulk of countries that did not fit his theory (such as France and Italy with their oily, fatty cuisines) or that the “epidemic” followed a reduction in the amount of fat Americans consumed – not an increase.
Not surprisingly, the American Heart Association was unimpressed at first yet it later became a firm advocate. The change, though, was not because it had new evidence but because it had some new members writing the report – Keys himself and one of his friends! Their warnings made the cover of Time magazine and were picked up by the US Department of Agriculture, who then drew up health guidelines that said things like “butter is bad” and “margarine is good”: highly authoritative government advice that quite possibly killed many of the people who believed it.
Certainly bad science is a serious business. Take the dark history of psychosurgery – of forced electric shock treatment and axes in brains. If that seems to belong more to horror films than the healing arts, in fact, today the same approach – only using different tools – has become mainstream in the form of mind-altering drugs. In the 1960s, these used to be things taken by hippies and searched for by police, but nowadays psychoactive drugs are routinely prescribed by doctors. It all illustrates the wisdom of the caustic remark of the inventor of homeopathy, Samuel Hahnemann that: “A qualified doctor is, of course, at liberty to give anything they like: Nature must submit out of respect for their diploma”.
An astonishing one child in five in the US is diagnosed as suffering from some kind of mental illness – and almost invariably treated this way. If the UK and Ireland have traditionally been more wary, the trend is definitely towards increased prescription of powerful chemicals for a whole range of dubiously defined “illnesses” such as schizophrenia, attention deficit hyperactivity disorder and depression. A perception of “big science” as infallible obscures the reality that there is a great deal of uncertainty in the current state of knowledge. The public seem not to be interested that, as with so many areas of medical science, the facts are much disputed and the efficacy of treatments highly debatable. Modern healthcare is built on naive public faith in technology and highly trained medical experts even though what has really improved public health has been better diet and sanitation.
Did I say “faith”? But curiously, there is a definite religious subtext to many scientific disputes. Take the great story of the battle between the Catholic Church and Copernicus and Galileo over whether or not the Earth went around the Sun. It is supposed to show how scientific method triumphed over ideology and superstition – but the reality was, if anything, quite the reverse. Copernicus, after all, was a dutiful Catholic priest who dedicated his book to the then Pope – who “received it cordially”! And yes, it’s true that Copernicus was concerned about the book’s reception and did delay its publication until after his death out of fear – but not fear of the Catholic Church, but of the scientific experts of the time, the academic authorities in the “schools” who were, almost to a professor, devoutly Aristotelian in outlook. It was the philosopher, not the Catholic Church, who created the dogma that the Earth must be motionless at the centre of the universe. And if textbooks endlessly repeat how Galileo’s new-fangled telescope “proved” his hypotheses, at the time, observational evidence, including crucially the lack of any observable parallax effect on the stars, supported the Church’s position. However, it is the winners who write the history of science.
Other great disputes also turn out, on closer examination, to really be surrogate battles between scientists with different, external, moral commitments. The battle between Louis Pasteur, a committed Catholic, and the then scientific establishment to prove that life cannot spontaneously generate from simple chemical reactions is one such. Pasteur is rightly one of the great names in the history of science and medicine, yet, in his lifetime, he was a hate figure and the object of intense opposition by almost the entire scientific establishment, precisely because of his opposition to the established views of the Ancients as well as, to a lesser extent, because of his resistance to the new ideas of his English contemporary, Charles Darwin.
The point is that science needs freedom of debate and scepticism, or it quickly becomes a more dangerous dogma than those it claims to be challenging. Whether it’s biochemists arguing over the origins of life, physicists arguing over the existence of the interstellar aether or climate scientists arguing over the drivers of the Earth’s weather, we need to remain sceptical. Because it is only by highlighting all the contradictions and inconsistencies in expert opinion and theory that the way is cleared for new, and likely better, ideas.
