Mythconceptions About Science

by Alec Burton, M.Sc.,D.C.,D.O.

“Science is physics, all the rest is stamp collecting.”

Ernest Rutherford, 1871 – 1937

Science is highly regarded in modern society, and it is the common belief that there is something extraordinary and special about the enterprise.  It is thought to be a constantly expanding source of objective and reliable knowledge.  I think that science is one of the most useful activities ever conceived by the human mind and the results of its application are all around us. We are frequently lost in wonder.

However, as we may perceive its many results and benefits, we must also acknowledge its limitations. The high regard we have for science has elevated it to a position of a modern religion, but the common beliefs about it are unjustifiable.  For example, we have all read conflicting news re-

ports where one day they might announce that low-fat diets are healthy, and another day they might announce that high-fat diets are healthy.  And both reports claim to use science to support their conclusions!  How can we make sense of all of this in our search for the most reliable information about health?  To understand this problem, we must look closely at what science is, and what it is not.

Science does not prove things nor does it disprove them. Scientific theories do not claim to be true, but probably more true than the theories they displace.[1] Galileo (1564-1642) was successful in understanding the world through mathematical theories of motion, and then Newton (1642-1727) discovered important and significant improvements, which were tested countless times for hundreds of years.  Nevertheless, Einstein (1879-1955) exposed the errors in the previous theories and presented a radically different way of looking at the universe.

The origins of modern science can be traced back to Sir Francis Bacon (1561-1626), Lord Chancellor of England, a lawyer, philosopher and outstanding literary man, who gave a method of acquiring natural knowledge in his  “Novum Organum,”  published in 1620. It was a project that had not been explored much since the time of Aristotle (384-322 BC).

Until recently, it was believed that there was some special kind of approach that scientists practice called the scientific method.  This idea has largely faded through the work of Paul Feyerabend whose book Against Method[2] caused an absolute storm among philosophers when it was published in the 1970s, although his ideas are generally accepted now.  Much has happened in the past four centuries which is well documented in John Gribbin’s book Science: A History (1543 – 2001),[3] an epic and exciting work for anyone interested in science.

The scientific practice was formally analyzed by Thomas Kuhn (1922 – 1996) in his masterful work The Structure of Scientific Revolutions.[4] In this book, he introduced the term paradigm, a conceptual world view made up of theories, experiments and classical methods which seem adequate to de-scribe particular phenomena at the time.  But as knowledge advances, the inadequacies of the paradigm are exposed and a crisis arises which can only be resolved by a paradigm shift. Historically, such paradigm shifts were the displacement of Ptolemy’s cosmology by the Heliocentrism of Copernicus, and the replacement of Newtonian theories by those of Einstein and quantum mechanics.

The crucial defining characteristic of science is the type of reasoning it employs which, in philosophy, is called the problem of induction. Inductive reasoning is a process that goes from empirical premises to empirical conclusions, supported by the premises, but not deduced from them.  To contrast, in deductive reasoning, the conclusion is implicit in the premise.  For example,

     All men are mortal

     Socrates is a man

     Therefore Socrates is mortal

This is not the case with inductive reasoning, which is the inverse process, reasoning from the particular to the general. It is based on the assumption that if something is true in a number of observed occasions, it is also true on other occasions, although not observed. An example of this is the common opinion poll where the opinion of a small percentage is projected to the total population. It is not difficult to see that there are problems with this.

This leads to the issue of causation and the sceptics’ rejection of scientific principles or laws.  The philosopher David Hume (1711 – 1776)[5] was quite devastating in his rejection of the idea of causation. He said,  “Reason can never show us the connection of one object with another, though aided by experience, and the observation of their conjunction in all past instances.”  Hume argued that there is no necessary connection between cause and effect.  Hume’s influence was enormous and led to Immanuel Kant (1724-1804) developing his critical philosophy as a direct reaction to Hume.

Science is based on the inductive method of reasoning, and predicting natural events and occurrences are its forte. However, if you want to see how difficult and unreliable this can be, study the weather reports. This is science in action. When it comes to foretelling the future the difficulties are enormous, and no matter how many times an effect is observed following a particular cause, it is not possible to predict the outcome with perfect accuracy.

Bertrand Russell tells the story of the inductivist turkey who lived on the turkey farm in quiet confidence. He was fed every morning, given drink, his pen was dutifully cleaned and his environment tidied. He lived the good life and knew what to expect every day. Then one day, as Christmas approached, his keeper visited and cut his throat.

When one reads the voluminous literature on the philosophy of science, almost all the interesting examples are from physics. They are not from the life sciences, and they are not from the study of health.  In physics, it is possible, although difficult, to control the variables. It is virtually impossible in biology.  Of course, complex statistical methods are employed to counteract this problem, but it is still basically true, as Lord Rutherford stated,  “Science is physics.”

One of the best books on the philosophy of science is The Logic of Scientific Discovery[6] by Sir Karl Popper.  In this work, the author introduces the concept of falsifiability (or testability).  Scientific theories are essentially conjectures that are testable.  If theory is not capable of being falsified, it is not scientific.  In Hygiene, we are all familiar with the appealing “enervation-toxemia theory” which has enormous explanatory power, but it cannot be tested or falsified.  It is not scientific.[7],[8] In medicine the same criticism may be made against psychoanalysis; it is impossible to falsify.

This is not to suggest that a theory or position that is not scientific is not useful; science is not applicable to all areas of knowledge. This was a problem that pervaded the philosophers and scientists of the Vienna Circle in the 1920s. The movement came to be known as Logical Positivism, and a fundamental tenet they espoused was the verification principle, that only propositions based on experience and observation were meaningful. Its narrow vision was soon exposed but aspects of the philosophy, significantly modified, are extant today.

In our quest for knowledge we need both philosophy and science and we should vigorously guard against the tendency to elevate science to an unjustified position as the only source of reliable knowledge.  This is especially true in the study of health, where one must utilize experience and reason as natural guides.