PureInsight | August 11, 2003
[PureInsight.org] What is science? Scientists and philosophers disagree on what it is. Any strict definition of science seems to be inadequate. One positive outcome of these issues is that they can help us to break through rigid notions of science and open our minds to possibilities of what science can be. But we must be careful that we do not fall into superstition or pseudo-science that leads us away from the truth. Although there might not be a single definition of science that could satisfy every reasonable person, a genuine science should lead us closer to the truth.
One of the reasons why there can be fundamental differences in opinion between scientists is that the basis of their opinion is largely philosophical and not entirely scientific. Of course, the things that scientists and philosophers normally do are quite different. However, although scientists have distinguished themselves from philosophy long ago, basic advances in modern science were influenced by philosophy. In turn, advances in science also influenced the development of philosophy. Much of modern science and mathematics developed along with philosophy, and the ties cannot be completely severed. Much of modern science still rest largely on a philosophical foundation although many scientists seem to have forgotten this.
The main point here is that the very starting point of modern science is not based on absolute certainty. Instead, the foundation of modern science has been and continues to rely on speculative philosophy. Even the same data from observations of the same physical phenomenon can be interpreted in very different ways depending on one's philosophical point of view. And the most precise mathematical statements also may be interpreted differently on how they relate to reality depending on one's philosophical point of view. This has important consequences on how (or whether or not) we can relate modern scientific theory with the truth of the universe.
This short article will present a brief sample of some fundamental controversies in modern science and philosophy of science.
Many mainstream scientists and philosophers believe that modern physics is the most mature and reliable science. Nevertheless, there have been controversies even at the heart of modern physics. Stephen Hawking is regarded as one of the most brilliant theoretical physicist of our time. He wrote:
"Any sound scientific theory, whether of time or of any other concept, should in my opinion be based on the most workable philosophy of science: the positivist approach put forward by Karl Popper and others. According to this way of thinking, a scientific theory is a mathematical model that describes and codifies the observations we make. A good theory will describe a large range of phenomena on the basis of a few simple postulates and will make definite predictions that can be tested… If one takes the positivist position, as I do, one cannot say what time actually is. All one can do is describe what has been found to be a very good mathematical model for time and say what predictions it makes." (The Universe In a Nutshell , p31)
Stephen Hawking is a positivist, as he also explained in his other writings. Positivism was popular decades ago, and its strong influence can still be felt today. However, many mainstream scientists and philosophers no longer agree with it entirely. Prominent scientists have opposed it since the time of Ernst March who helped to advance positivism:
"The distinguished physicist Max Planck, for example, maintained that Mach's [positivism]…, if generally accepted, would fatally impair the progress of science itself by crippling the scientific imagination and the scientist's faith in his own work as a true representation of reality. Others have held that the dignity of science as the supreme vehicle of human knowledge would disappear if the theories of natural science should generally be thought of as nothing more than a system of convenient summary of formulas for predicting the occurrence of sensations. Even Einstein, despite his great admiration for Mach, sometimes seems to have opposed positivism, in his later years…" (The Age of Ideology , p253-254)
We know that scientists disagree on various theories, but this disagreement on a central feature of positivism is more fundamental than any theory choice. This shows a difference in opinion, not just about any particular theory, but a difference in opinion about any conceivable theory in modern physics. Can a scientific theory truly represent reality or is it just an abstract model that goes no further than to describe observations? It is a question about whether or not we can really understand the truth of the universe with modern scientific theories.
Positivism itself was founded by Auguste Comte, a 19th century philosopher. In fact, many pioneers of modern science have been influenced by philosophy. Einstein himself spent a great deal of time studying and writing about philosophy and science, and philosophers such as Ernst Mach and David Hume had a strong influence on the development of Einstein's scientific theories. He once wrote:
"I can say with certainty that the study of Mach and Hume has been directly and indirectly a great help in my work…" (Albert Einstein Philosopher-Scientist , p272)
A striking example of how differences in philosophical points of view can dramatically affect important scientific theories can be seen in debates between Roger Penrose and Stephen Hawking. They debated about fundamental aspects of the nature of the universe. And much of the disagreements between them and the divergence of their theories arose from their very different philosophical points of view. Hawking said,
"These lectures have shown very clearly the difference between Roger and me. He's a Platonist and I'm a positivist." (The Nature of Space and Time, p120)
Most practicing modern scientists do not concern themselves with philosophy in their daily work. They merely tend to use well-established theories toward some application. In a way, philosophy and modern science are different. However, for pioneering scientists who try to break through the limitations of current theories, they occasionally have to deal with deep philosophical issues. Today, philosophy still plays an important role in the development of theoretical physics. From Scientific American, George Musser made it clear that physicists are still seeking help from philosophers. He wrote,
"Philosophy played a crucial role in past scientific revolutions, including the development of quantum mechanics and relativity in the early 20th century." (Scientific American, September 2002, p48)
And now, decades later, a leader of the effort in trying the merge quantum mechanics and relativity into quantum gravity, Carlo Rovelli said,
"The contributions of philosophers to the new understanding of space time in quantum gravity will be very important." (Scientific American, September 2002, p48)
In an earlier quote above, Stephen Hawking mentioned the "positivist approach put forward by Karl Popper and others". Karl Popper was a philosopher who made important contributions to philosophy of science and has influenced many scientists. In Science: Conjectures and Refutations, he wrote:
"'When should a theory be ranked as scientific?' or 'Is there a criterion for the scientific character or status of a theory?'… I wish to distinguish between science and pseudo-science;"
This addresses our first question: what is science? Popper proposed that falsification is the criterion:
"…the criterion of falsifiability… [is the solution to] the problem of drawing a line… between the statements, or systems of statements, of the empirical sciences, and all other statements – whether they are a religious or of a metaphysical character or simply pseudo-science."
For example, Einstein's theory of gravitation is considered to be falsifiable because the theory makes precise claims that can be tested by rigorous empirical methods and can be refuted if it failed the tests. In 1919, Eddington's eclipse observation confirmed that light bends around the strong gravitational force of the sun just as Einstein's theory predicted. Had the observation been different, the theory could have been refuted. That observation only showed that the theory passed the particular test, and it does not say that the theory is entirely correct since it can still fail other tests in the future. Basically, if a theory is falsifiable, then although the entire theory cannot be proven to be true for all cases, it can be tested with empirical methods to check for defects. Then it should be possible for science to check itself and improve. This is how science is supposed to advance. Many modern scientists believe that falsifiability is a necessary feature of a scientific theory.
However, Thomas Kuhn, who is the author of The Structure of Scientific Revolutions, disagreed with Popper. According to Kuhn, scientists tend to be dogmatic in seeking confirmation of established paradigm even in the light of conflicting data. Scientists stubbornly try to fit observed anomalies into their paradigm. Scientific revolutions have occurred in history, but only rarely, when an entire paradigm is in crises. In short, according Kuhn, falsifiability cannot be a criterion of science because it excludes the larger aspect of what scientists actually do. In Logic of Discovery or Psychology of Research, Khun wrote:
"...a careful look at the scientific enterprise suggests that it is normal science, in which Sir Karl's sort of testing does not occur, rather than extraordinary science which most nearly distinguishes science from other enterprises. If a demarcation criterion exists (we must not, I think, seek a sharp or decisive one), it may lie just in that part of science which Sir Karl ignores." (Philosophy of Science, p. 14).
Thomas Kuhn is the author of The Structure of Scientific Revolutions. And although Thomas Kuhn may be the most widely studied writer in Philosophy and History of Science, he does not have the last word. Other notable philosophers and scientists criticize him on various fundamental aspects of science.
These controversies between some of the most distinguished experts on science are just a tip of the iceberg. In Philosophy of Science, Martin Curd and J. A. Cover wrote:
"…[there are] many sharp disagreements within the philosophy of science and [there is an] unresolved character of nearly all the fundamental questions that philosophers ask about science" (p. xix)."…we have explored a number of attempts to demarcate science from pseudoscience. But the results have been curiously inconclusive…. It is highly unlikely that any simple minded, one- or two-sentence definition of science will yield a plausible demarcation criterion that we can use to label and condemn as pseudo scientific…" (p77-79).
One thing is for sure. Currently, there is no strict definition of science that can satisfy every reasonable person. Many very capable people have struggled with fundamental issues of science for many decades, and there are no indications that they are getting any closer to resolving them. Although we must be careful to not fall into pseudoscience, we must be equally careful to not reject certain possibilities of what science can be. These issues bring us back to our first question: what is science? Although we may not be able to give a precise definition, one possibility shines through: science does not have to be just like modern science.
Mr. Li Hongzhi once said, "If human beings are able to take a fresh look at themselves as well as the universe and change their rigid mentalities, humankind will make a leap forward."
Curd, Martin and J. A. Cover (1998), Philosophy of Science. W. W. Norton & Company, Inc.
Hawking, Stephen (2001), The Universe In a Nutshell. A Bantam Book.
Hawking and Penrose (1996), The Nature of Space and Time. Princeton Science Library.
Kuhn, Thomas S. (1962), The Structure of Scientific Revolutions (3rd edition). The University of Chicago Press.
Musser, George, "A Hole At The Heart of Physics", Scientific American, September 2002.
Schilpp, Paul Arthur (1970), Albert Einstein Philosopher-Scientist, Open Court Publishing Company.
