How Science Changes

Science is different from pseudoscience, and history is different from pseudohistory, not only in evidence and plausibility but in how they change. Science and history are cumulative and progressive in that they continue to improve and refine knowledge of our world and our past based on new observations and interpretations. Pseudohistory and pseudoscience, if they change at all, change primarily for personal, political, or ideological reasons. But how does science and history change?

One of the most useful theories of how science changes is Thomas Kuhn's
(1962) concept of “paradigm shift”. The paradigm defines the “normal science” of an age- as accepted by the majority of the practicing scientist in a field- and a shift (or revolution) may occur when enough renegade and heretical scientist gain enough evidence and enough power to overthrow the existing paradigm. “Power” is made visible in a social and political aspects of science: research and professional positions at major universities, influence with funding agencies, control of journals and conferences, prestigious books, and so forth. I define a paradigm as a model shared by most but not all members of a scientific community, designed to describe and interpret observed or inferred phenomena, past or present, and aimed at building a testable body of knowledge open to rejection or confirmation. In other words, a paradigm captures the scientific thinking of the majority but most of the time it coexist with competing paradigms – as id necessary if new paradigms are to displace ole paradigms.

Stacks Image 873

Philosopher of science Michael Ruse, in The Darwinian Paradigm
(1989), identified at least four usages of the word.

1) Sociological, focusing on “a group of people who come together, feeling themselves as having a shared outlook (whether they do really, or not) and to an extent separating themselves off from other scientist” (pp.124-125). Freudian psychoanalyst with psychology are a good example of science guided by a sociological paradigm.

2) Psychological, where individuals within the paradigm literally see the world differently from those outside the paradigm. We have all seen the reversible figures in perceptual experiments, such as the old women/ young women shifting figures where the perception of one precludes the perception of the other. In this particular perceptual experiment, presenting subjects with a strong “young women” image followed by the ambiguous figure always produces the perception of the young women, while presenting a strong “old women” image followed by an ambiguous figures produces the perception of the old women 95 percent of the time (leeper 1935). Similarly, some researchers view aggression in humans primarily as biologically innate and essential, while others view it primarily as culturally induced and dispensable.

3) Epistemological, where “one's ways of doing science are bound up with paradigm” because the research techniques, problems, and solutions are determined by hypotheses, theories, and models. A theory of phrenology that leads to the development phrenological equipment for measuring bumps on the skull would be an example of science guided by an epistemological paradigm.

4) Ontological, where in the deepest sense “what there is depends crucially on what paradigm you hole. For Priestley, there literally was no such thing as oxygen...In the case of Lavoisier he not only believed in oxygen: oxygen existed” (pp. 125-126). Similarly, for Georges Buffon and Charles Lyell, varieties in a population were merely degenerates from the originally created kind; nature eliminated them to preserve the essence of the species. For Charles Darwin and Alfred Russel Wallace, varieties were the key to evolutionary change. Each view depends on a different ontological paradigm. Buffon and Lyell could not see variations as evolutionary engines because evolution did not exist for them; Darwin and Wallace did not view varieties as degenerative because degeneration is irrelevant to evolution.

Stacks Image 877

My definition of a paradigm shift holds for sociological, psychological, and epistemological uses. To make it wholly ontological, however, would mean that any paradigm is as good as any other paradigm because there is no outside source for corroboration. Tea-leaf reading and economic forecasting, sheep's livers and meteorological maps, astrology and astronomy, all equally determined reality under an ontological paradigm. This is not even wrong. It is ridicules. As difficult as it is for economist and meteorologist to predict the future, they are still better at it than tea-leaf readers and sheep's liver diviners. Astrologers cannot explain the interior workings of a star, predict the outcome of colliding galaxies, or chart the course of a spacecraft to Jupiter. Astronomers can, for the simple reason that they operate within the scientific paradigm that is constantly refined against the harsh realities of nature itself.

Science is progressive because its paradigms depends upon the cumulative. Pseudoscience, non-science, superstition, myth, religion, and art are not progressive because they do not have goals or mechanisms that allow the accumulation of knowledge that builds on the past. Their paradigms either do not shift or coexist with other paradigms. Progress, in the cumulative sense, is not their purpose. This is not a criticism, just an observation. Artist do not improve upon the styles of their predecessors; they invent new styles. Priests, rabbis, and ministers do not attempt to improve upon the sayings of their masters; they repeat, interpret, and teach them.

By cumulative change I mean, then, that when a paradigm shifts, scientist do not abandon the entire science. Rather, what remains useful in the paradigm is retained as new features are added and new interpretations given. Albert Einstein emphasized this point in reflecting upon his own contributions to physics and cosmology: “Creating a new theory is not like destroying an old barn and erecting a skyscraper in its place. It is rather like climbing a mountain, gaining new and wider views, discovering unexpected connections between our starting point and its rich environment. But the point from which we started out still exists and can be seen, although it appears smaller and forms a tiny part of our broad view gained by the mastery of the obstacles on our adventurous way up” (in Weaver 1987, p133). Even though Darwin replaced the theory of special creation with that of evolution through natural selection, much of what came before was retained in the new theory – Linnean classification, descriptive geology, comparative anatomy, and so forth. What changed was how these various fields were linked to one another through history – the theory of evolution. There was cumulative growth and paradigm change. This is scientific progress, defined as the cumulative growth of a system of knowledge over time, in which useful features are retained and non-useful features are abandoned, based on the rejection or confirmation of testable knowledge.

Michael Shermer
Why people believe weird things (Chapter two) 1997

"I don't want to gain immortality through my work; I want to gain immortality through not dying" Woody Allen

Stacks Image 883