by David Ragsdale, PhD

It is commonplace, nowadays, to come across words such as "scientific" and "unscientific" used to support or condemn various claims. The American politician Sharon Angle has asserted that the evidence for global warming is "junk science". Purveyors of homeopathic remedies refer to "scientific" evidence in support of their products' effectiveness. In cases like these, the terms "scientific", "junk science" and so forth are being used in the same sense that North Korea calls itself a "Democratic People's Republic" or that Rush Limbaugh calls Barak Obama a "fascist". "Scientific" merely means something that the speaker or writer wants us to believe is good, something that can be taken seriously, whereas "unscientific", "junk science", etc. mean just the opposite. In other words, these terms have been stripped of any deep meaning, and are simply intended to convey praise or condemnation.

It's no real surprise that know-nothing politicians and charlatans use and abuse words that they don't understand. But, even for scientists, the meanings of terms such as "scientific" and "scientific method" are not necessarily obvious, nor are the precise boundaries that circumscribe scientific activities always clear. Scientists firmly believe that science is a distinct, identifiable process and that the methods of science are revealing truths about nature. But then, most everyone, from birthers, to truthers, thinks that their beliefs and underlying assumptions are "true". What, if anything, makes science different or special? What is it, for example, that makes the scientific assertion that the earth is 4.6 billion years old more plausible than the contention of creationists that the universe was created six thousand years ago and that dinosaurs and humans lived at the same time? If you're like me, you believe the scientists, but why? After all, most of us have no idea how to determine the age of rock samples, so why should we put our trust in the scientists who claim that they do? We've all heard of the "scientific method", but what is it and what makes it different and better than other ways of understanding nature?

Perhaps the most famous modern attempt to articulate the scientific method was developed by the Austrian philosopher Karl Popper (1902 - 1994). Popper saw science as a logical process of hypothesis-testing. A scientific hypothesis or theory, according to Popper, is a statement about nature that can, at least in principle, be proven false. Thus, for example, the contemporary theory that anatomically modern humans first evolved around two hundred thousand years ago is scientific, because it would be proven false by the (very unlikely) discovery of a seventy million year old fossilized human skeleton. Another key idea, according to Popper, is that scientific theories are never proven true; they are simply retained until proven false. In other words, all scientific theories are tentative; they are the best explanations we have at present.

Popper's conception of the scientific method has been highly influential; however, it describes only a small fraction of what actually goes on in scientific research, leaving out such essential elements as creativity, insight, the development and use of technology, and much more. Furthermore, Popper's highly logical, linear conception fails to capture the complex social dimensions of science, an area that has been of particular interest to contemporary philosophers. The most influential thinker in this regard was the American physicist and philosopher Thomas Kuhn (1922 - 1996), whose book, The Structure of Scientific Revolutions, was a landmark in the philosophy of science. Kuhn argued that science, in a particular field at a particular point in history, is defined by what he called a "paradigm". A paradigm is a world view that determines what types of questions a scientist can reasonably ask and how she interprets her results. For example, in the early 20th century, most astronomers believed in a steady-state universe that had existed forever and didn't change. However, in the late 1920's, Edwin Hubble described his observations showing that distant galaxies are moving away from us; the farther away they are, the faster they are moving. These and subsequent data led to a paradigm shift: from the steady-state model to the idea of a universe that started with a big bang 13.7 billion years ago, and has been expanding ever since. Modern cosmologists frame their questions about the universe in terms of the big bang paradigm. According to Kuhn, the shift from one paradigm to another is somewhat like a religious conversion; it is a social phenomenon, involving the rapid emergence of a new consensus, when it becomes evident that an old paradigm is inadequate and a new, more powerful paradigm is available to take its place. Kuhn was himself a scientist, who wanted to understand and interpret science history. Unfortunately, his work has served as a key reference for many modern critics who regard science as, at best, just one more form of human story-telling and, at worst, a justification for destruction of the environment, oppression of the weak and so forth.

So what is science? Is there a unique scientific method? Poppers view was too linear and deductive to capture the reality of the scientific enterprise. Some modern thinkers have likened science and scientific knowledge to a vast interconnected web. The contemporary philosopher Susan Haack has suggested the metaphor of a crossword puzzle, in which some entries are in pen (things we are confident of) and others in pencil (things we are not so sure about) and in which the various intersecting entries (e.g. 4 down and 28 across) mutually reinforce each other.

Questions concerning what constitutes science and what gives science its claim to veracity are not mere philosophical musings. The view that modern science is just one more dishonest and self-serving institution is surprisingly pervasive and influential in some academic fields and more generally in modern society, which is increasingly distrustful of institutions of all kinds and has access to unfiltered information from every conceivable perspective through the internet. This anti-science meme obscures the role that scientific literacy plays in crucial issues, from global warming to the alleged link between vaccination and autism to purported health risks in our food and environment, and much, much more. Perhaps the most important role of contemporary science education is to teach people to consider these and other vital issues in terms of honest, critical and rational analysis of data obtained through careful observation - in other words, to think about them scientifically - rather than in terms of prejudice, wish-fulfillment or the furthering of ideological agendas.

David Ragsdale, Assistant Professor, joined the faculty at The Neuro in 1995 after completing his PhD at the University of California, Irvine, and post-doctoral training at the University of Washington. In 2008, David was named to the McGill Faculty of Medicine Honor List for Educational Excellence.