Christine V. McLelland GSA Distinguished Earth Science Educator in Residence Reviewers and Contributors: Gary B. Lewis Director, Education and Outreach, Geological Society of America Contributing GSA Education Committee members: Rob Van der Voo University of Michigan, Ann Arbor, Mich. Keith A. Sverdrup University of Wisconsin, Milwaukee, Wis. Mary M. Riestenberg College of Mount Saint Joseph, Cincinnati, Ohio Virginia L. Peterson Grand Valley State University, Allendale, Mich. Wendi J.W. Williams University of Arkansas, Little Rock, Ark. Sandra Rutherford Eastern Michigan University, Ypsilanti, Mich. Larissa Grawe DeSantis University of Florida, Gainesville, Fla. Aida Awad Des Plaines, Ill. Stephen R. Mattox Grand Valley State University, Allendale, Mich. Steve Boyer Tacoma, Wash. Jo Laird University of New Hampshire, Durham, N.H. Cover image: A basalt dike cuts through rocks of Permain age on Wasp Head, NSW Australia. Photo by Gary B. Lewis. Table of Contents What is Science? . 1 Scientifi c Method . 2 Observation . 2 Question . 2 Hypothesis. 2 Experiment . 3 Evaluation . 4 Defi nitions. 4 Fact:. 4 Hypothesis: . 4 Scientifi c Theory (or Law): . 4 Science Through the Recent Ages. 5 Scientifi c Method and Earth Sciences . 6 Conclusion . 7 Talking Points about Science . 8 On the Nature of Science . 8 On Evolution, Creation Science, and Intelligent Design . 8 Bibliography and Additional Resources . 9 iii Nature of Science and the Scientifi c Method “The most incomprehensible thing about the world is that it is comprehensible.” —Albert Einstein What is Science? false is not amenable to scientifi c investigation. Explanations that cannot be based on empirical evidence are not a part of sci- Science is a methodical approach to studying the natural ence (National Academy of Sciences, 1998). world. Science asks basic questions, such as how does the world Science is, however, a human endeavor and is subject to work? How did the world come to be? What was the world like personal prejudices, misapprehensions, and bias. Over time, in the past, what is it like now, and what will it be like in the however, repeated reproduction and verifi cation of observations future? These questions are answered using observation, test- and experimental results can overcome these weaknesses. That ing, and interpretation through logic. is one of the strengths of the scientifi c process. Most scientists would not say that science leads to an Scientifi c knowledge is based on some assumptions (after understanding of the truth. Science is a determination of what is Nickels, 1998), such as most likely to be correct at the current time with the evidence at • The world is REAL; it exists apart from our sensory per- our disposal. Scientifi c explanations can be inferred from con- ception of it. fi rmable data only, and observations and experiments must be • Humans can accurately perceive and attempt to under- reproducible and verifi able by other individuals. In other words, stand the physical universe. good science is based on information that can be measured or • Natural processes are suffi cient to explain or account seen and verifi ed by other scientists. for natural phenomena or events. In other words, scien- The scientifi c method, it could be said, is a way of learning tists must explain the natural in terms of the natural (and or a process of using comparative critical thinking. Things that not the supernatural, which, lacking any independent are not testable or falsifi able in some scientifi c or mathematical evidence, is not falsifi able and therefore not science), way, now or in the future, are not considered science. Falsifi - although humans may not currently recognize what those ability is the principle that a proposition or theory cannot be sci- processes are. entifi c if it does not admit the possibility of being shown false. • By the nature of human mental processing, rooted in Science takes the whole universe and any and all phenomena in previous experiences, our perceptions may be inaccu- the natural world under its purview, limited only by what is fea- rate or biased. sible to study given our current physical and fi scal limitations. • Scientifi c explanations are limited. Scientifi c knowledge Anything that cannot be observed or measured or shown to be is necessarily contingent knowledge rather than abso- lute, and therefore must be evaluated and assessed, and is subject to modifi cation in light of new evidence. It is impossible to know if we have thought of every possible alternative explanation or every variable, and technology may be limited. • Scientifi c explanations are probabilistic. The statistical view of nature is evident implicitly or explicitly when stating scientifi c predictions of phenomena or explaining the likelihood of events in actual situations. As stated in the National Science Education Standards for the Nature of Science: Scientists formulate and test their explanations of nature using observation, experiments, and theoretical and mathematical models. Although all scientifi c ideas are tentative and subject to change and improvement in principle, for most major ideas in science, there is much experimental and observational con- fi rmation. Those ideas are not likely to change greatly in the future. Scientists do and have changed their ideas about nature when they encounter new experimental evidence that does not match their existing explanations. (NSES, 1996, p. 171) Layers rocks making up the walls of the Grand Canyon. 1 The Nature of Science and the Scientifi c Method 2 The Standards for Science Teacher Preparation correctly elements that are applicable to most experimental sciences, state that such as physics and chemistry, and is taught to students to aid their understanding of science. Understanding of the nature of science—the goals, values and That being said, it is most important that students realize assumptions inherent in the development and interpretation of that the scientifi c method is a form of critical thinking that will scientifi c knowledge (Lederman, 1992)—has been an objective of science instruction since at least the turn of the last century. be subjected to review and independent duplication in order to It is regarded in contemporary documents as a fundamental reduce the degree of uncertainty. The scientifi c method may attribute of science literacy and a defense against unquestioning include some or all of the following “steps” in one form or acceptance of pseudoscience and of reported research. Knowl- another: observation, defi ning a question or problem, research edge of the nature of science can enable individuals to make (planning, evaluating current evidence), forming a hypothesis, more informed decisions with respect to scientifi cally based issues; promote students’ in-depth understandings of “tradi- prediction from the hypothesis (deductive reasoning), experi- tional” science subject matter; and help them distinguish sci- mentation (testing the hypothesis), evaluation and analysis, ence from other ways of knowing… peer review and evaluation, and publication. Research clearly shows most students and teachers do not Observation adequately understand the nature of science. For example, most teachers and students believe that all scientifi c investiga- tions adhere to an identical set of steps known as the scientifi c The fi rst process in the scientifi c method involves the method, and that theories are simply immature laws. Even when observation of a phenomenon, event, or “problem.” The dis- teachers understand and support the need to include the nature covery of such a phenomenon may occur due to an interest on of science in their instruction, they do not always do so. Instead the observer’s part, a suggestion or assignment, or it may be they may rely upon the false assumption that doing inquiry leads an annoyance that one wishes to resolve. The discovery may to understanding of science. Explicit instruction is needed both to prepare teachers and to lead students to understand the nature even be by chance, although it is likely the observer would be of science. (NSTA, 2003, and references therein, p. 16) in the right frame of mind to make the observation. It is said that as a boy, Albert Einstein wanted to know what it would be like to ride a light beam, and this curious desire stuck with him Scientifi c Method throughout his education and eventually led to his incredible theories of electromagnetism. Throughout the past millennium, there has been a real- ization by leading thinkers that the acquisition of knowledge Question can be performed in such a way as to minimize inconsistent conclusions. Rene Descartes established the framework of the Observation leads to a question that needs to be answered scientifi c method in 1619, and his fi rst step is seen as a guiding to satisfy human curiosity about the observation, such as why or principle for many in the fi eld of science today: how this event happened or what it is like (as in the light beam). In order to develop this question, observation may involve tak- …never to accept anything for true which I did not clearly know ing measures to quantify it in order to better describe it. Scien- to be such; that is to say, carefully to avoid precipitancy and tifi c questions need to be answerable and lead to the formation prejudice, and to compromise nothing more in my judgment than what was presented to my mind so clearly and distinctly of a hypothesis about the problem. as to exclude all ground of methodic doubt. (Discours de la Méthode, 1637, section I, 120) Hypothesis By sticking to certain accepted “rules of reasoning,” scien- To answer a question, a hypothesis will be formed. This is tifi c method helps to minimize infl uence on results by personal, an educated guess regarding the question’s answer. Educated social, or unreasonable infl uences. Thus, science is seen as a is highlighted because no good hypothesis can be developed pathway to study phenomena in the world, based upon repro- without research into the problem.