Jan Andrea
Topics in the History of Science
13 March 1997
Introduction: Why Teach the History of Science in a Science Class?
It is the end of the twentieth century. Science and technology are gaining ever more importance in everyday life. New discoveries and inventions bring with them astounding possibilities for the betterment of humanity's standard of living... as well as the need to ensure that such possibilities do not also bring greater harm. It is therefore imperative that the population responsible for making such decisions be well educated, not only in the morality of technology's applications, but also in the science that lies behind each technology. A democracy familiar with the ways in which nuclear reactions occur in a power-generating facility, for example, would be better equipped to vote on its usage and limitations than is our current population.
It should be clear that science education is the key to producing a citizenry capable of handling the immense decisions that will be faced in the near future as a result of today's scientific breakthroughs. At no time during our past has so much information been available to the public; and yet the level of scientific understanding in the general population is appallingly low. A recent NSF survey of American adults found that fewer than one in ten could explain the structure of a molecule; just one in five could provide a "minimally acceptable definition" of DNA; and perhaps most disturbingly, only 49 percent were aware that the Earth revolves around the Sun once a year. These are concepts basic to the understanding of many new technologies ó even to the world in general ó and yet the very public that needs this information to adequately justify voting on such matters as research funding has no idea what that funding really means in terms of doing science.
One must ask, what is the cause of such distressingly low rates of scientific literacy? Where does the fault lie ó with educators; with media's love-hate relationship with science, and its portrayal of many discoveries as Frankenstein waiting to happen; or simply with a public attitude that science is not important to their daily lives? Clearly, there is no one scapegoat upon which the blame may be placed; surely there are areas in which all of the above may be improved.
As a future science educator, however, my concern is with the presentation of science in public schools, and especially within the junior high or middle school years. When one considers that many adults have had two or fewer years of science in high school, and those generally did not include physics or chemistry, the teaching of physical principles in the earlier grades becomes all the more crucial. The methods used to teach science at that age level may well determine the students' future attitude towards science in general. In my own experience, if the teacher uses methods that captivate and involve the students, those students are far more likely to show a continuing interest in the sciences; whereas if methods stressing memorization and recall are used, without actively engaging the students, they will probably develop a dislike for the rote memorization that they see as science.
The use of historical examples, vignettes, and theories in the teaching of science can provide a very real and far more personal learning experience for the average student. A student struggling with the concept of genetic change over time, for example, may find considerable comfort in the knowledge that it was only relatively recently that scientists began to understand it: s/he may greatly benefit from reading an account from a contemporary biologist who also found the concept difficult. The same is true of the basic concepts of the physical sciences: knowing that natural philosophers the likes of Galileo and Newton (of whom they will certainly have heard) struggled for years to reconcile the mathematics of movement with its more familiar real-world functions, the students will find that they have common ground even with such genius. The resultant relaxation can help them overcome conceptual difficulties that have arisen from their feelings of intellectual inadequacy .
The use of historical examples can also illustrate the changing and changeable nature of scientific inquiry. Too many students in the past were taught science as dogma: rather than a continuously evolving knowledge base, they were told that science was infallible, or even that it had some kind of quasi-magical window into the Ultimate Truth . If they can understand previous scientific theories in their historical context, however, it is much easier to see that the knowledge we have now is constantly being augmented and revised; this, too, may increase their desire to "do" science, since there is still so much to be learned and modified.
On occasion, examples in the history of science can also be used to predict possible student misconceptions, because in many ways, the students of today are in a similar position to natural philosophers of the past. They know the world, in essence, from their own observations. In their reality, it does take a constant force to create a constant velocity ó after all, if we push a block around on the table, it does not just keep moving after we let go: it stops. Without having the experience of motion in a vacuum, children are just as bound by their observations as were men of science five hundred years ago, who were quite certain that there was some kind of force constantly acting on bodies in motion, and that the state of rest was the "natural" state. If you were to ask a middle-school- aged student to explain why a block stops on a table, instead of going on indefinitely, they would likely give a similar explanation, without mentioning the force of friction. Friction is such a part of their lives that they do not generally think about it... just as would have been the case for scientists in the past.
In sum, there are many reasons to incorporate the history of science into science classrooms of all levels. But the "how" remains to be explored. I shall use the example of a traditionally difficult subject for early adolescents: the principles of motion.
Applications: Using the History of Science to Teach Basic Mechanics
The study of mechanics and motion has a long and torturous scientific history, its recorded portion going back to ancient Greece. Aristotle's ideas about motion and many other subjects remained in circulation for centuries after his death, and so he had a profound influence on the natural philosophers who followed him. Butterfield states that it was not closer observation that would change this ideology, but a fundamental shift in thinking ó any change in the conceptual framework surrounding motion could occur only through new modes of imagination, such as Galileo's vision of motion in a vacuum, and other such situations that could not ordinarily be experienced .
Almost every modern child is familiar with the thrill of pushing toy cars down a long hallway, or letting them slide down an incline. But those experiences present a more complex image than the idealized conception of motion: even the most well-oiled toy will eventually succumb to friction, leading the child to believe, if on a subconscious level, that motion requires a continuous input of force. It is this seemingly intuitive image that the teacher must strive to correct, and history presents many intriguing ways in which to do so.
When students "learn" about motion in the traditional manner ó that is, the teacher stands in front of the class and lectures about the scientific material, while the students passively take notes, which they will later memorize and repeat for the teacher ó they may come away from the lesson with some ideas about how motion works, but in all likelihood with more questions that answers. If, however, the students can somehow be engaged with the process that spawned the knowledge with which they are now confronted, they are far more likely to be able, not only to recall, but also to use that information later, and that is the ultimate goal of science education.
One approach to engaging students in a science class is storytelling. The use of historical vignettes is gaining popularity in many fields of education , precisely because it works: students are presented with a scenario, often involving a famous scientist (who may or may not at first be named) and a conflict ó scientific or social ó that must be solved. In the case of motion, there are many examples from which one can choose; however, the alternate explanations created by past scientists to explain motion pose a more interesting challenge to students. According to Butterfield, there are several:
1) The Aristotelian view: The natural state of an object is at rest, and a force is necessary to keep a body in motion. The greater the force, the greater its speed. If you push a book across a tabletop, it stops moving after you let go of it; but while you are pushing, the harder you push, the faster it goes.
2) From the middle ages: Objects are given a kind of motive force ó impetus ó when they are moved, and the more dense an object is, the more impetus it can hold. A stone, when thrown, can attain a greater distance than a ball of feathers because it has a greater density, and therefore is capable of containing more impetus, which, like the heat in a red-hot fireplace poker, is attained by being in motion ó being in the fire ó and stays with the object through its flight.
3) Galileo's view: An object in motion stays in motion, unless it encounters a force acting in an opposing direction. If you throw a stone into the air and it slows down, eventually falling to the ground, it is because some other forces are acting on the stone.
Each of these views makes a certain amount of sense, if you consider the common motions that the philosophers in cases 1 and 2 would have encountered. Presenting all three of the scenarios to a class, the teacher can ask the students to vote on the model that they think is the most accurate description of the world, and ó more importantly ó why. Of course, the students must first understand the terminology; "speed", "force", "density", and, in the case of number 2, "impetus", must all be explained, either by the teacher or a willing student. However, it is through the use of such terms that students gain a working understanding of the concepts behind them. Even if the students cannot give a textbook definition of the terms at the beginning of the discussion, through the use of examples and the like, they will have a better grasp of their meanings by the end of the class.
Quite a discussion may be generated by these scenarios, and the teacher should encourage students to talk to each other and not just to her. For example, there will probably be some students who feel that Aristotle was right; and some who feel that Galileo was correct. Each will have his or her justifications for that view. However, those on Galileo's side may bring up the point that there are satellites and probes in space that do not require motors; while those on Aristotle's side may resort to demonstrating the truth of his theory by sliding a book across the floor. (They may also turn to science fiction ó in Star Trek, for example, the Enterprise always has its motor running when it is in motion...)
More astute students may recognize the factor their peers are missing: friction. They will be able to perceive that there is a force stopping the book, not a natural inclination, and will likely be able to give several examples whereby the reduction of friction can lead to an increased distance traveled by the object. They will have made the same leap of imagination as did Galileo, and should be told so: "Many scientists ó or natural philosophers, as they were called then ó though the same way that Aristotle did, for thousands of years, because they could never experience a world without friction. They had never been to space, or seen the effects of a vacuum, or watched slapstick comedy, where a banana peel reduces friction between someone's shoe and the floor. But Galileo used his imagination, and made up a world where there was no air to slow down a stone in flight, and friction was reduced on the tabletop, so that one little push sent the book flying, without a constant force or impetus or anything. We may think that Aristotle and the scientists who followed him were a little silly for making up the explanations they did, but scientists try to explain things all the time: we look at the information we have available, we come up with a hypothesis that seems to fit all of those facts, and we test it and try to disprove the hypothesis. Can anyone think of a test that would have disproved Aristotle's hypothesis, given the technology they had back then?" This question alone may generate another discussion, as students realize how much the study of science has been limited by historical factors; many of the inventions we have used to support Galileo and Newton were impossible in Aristotle's time. It should quickly become clear to the students that many observations cannot be made now because we do not yet have the technology, and that the discoveries we are making now, would have been far more difficult in the past without current technology.
Another step in engaging student learning is to ask questions ó not coincidentally, also the first step in applying the scientific method. Not only does this bring the subject to the forefront of the students' minds; it also allows the teacher to discover what misconceptions exist that s/he must strive to correct. In terms of posing a question such that it will generate thought and answers, letting the students organize themselves into small groups is often an ideal way to allow students to discuss the question without the stress of speaking in front of a large group. This is especially useful at the beginning of the school year, when motion is often taught.
Now that students presumably have a firmer grasp on how theories change through time, and specifically how the concepts of motion have evolved, they should themselves experiment with the physics, or at least be shown a demonstration of falling bodies. In this case, it should be stressed that gravity is the force responsible for acceleration; this may be contrasted to the Aristotelian hypothesis that "earthy" objects tend naturally to fall towards the Earth (just as gases tend to rise towards the heavens). Students may again be asked to think of a test that would disprove Aristotle, both in his time and in our own (though the latter should be much simpler, given the existence of satellites in orbit and the like).
In terms of the scientific aspect of this exercise, much has already been written ó Carolina Scientific has entire pages devoted to the teaching of simple mechanics to this age group. But it is also fairly simple to devise historical tie-ins, such as the questions above; as well as the possibility of re-enactments: the students are probably all familiar by this time with the legendary experiment at the Tower of Pisa, where Galileo was supposed to have dropped two metal balls of dissimilar weight from the top of the tower, and observed that they both landed at the same time. Although the experiment did not actually take place, the thought experiment was still crucial; it could be quite amusing to have students create a play in which they demonstrate Galileo's thought processes. (It may seem superfluous to do such a thing in a science classroom, but research by Howard Gardner and others has shown that not all minds think alike, and for some students, a highly auditory and visual format such as a play may cement the ideas, where lecture and/or worksheets may not.)
Common Themes: Tying it All Together
One of the major advantages of a middle school format is the teaming aspect: teachers of math, science, English/reading, and social studies/history all work together, sometimes creating cross-curricular units. Thus, if the science teacher is uncomfortable with historical aspects, for whatever reason, s/he can leave it to the history teacher to cover those areas. The graphing skills helpful in understanding mechanics (e.g. plotting distance vs. time, velocity vs. time, simple integrals and their relationship to acceleration, etc.) can be taught before or during the mechanics unit. In this way, all of the necessary bases are covered without overloading the science teacher, and at the same time, providing valuable curricular points for the other teachers. For instance, it is probably more in the jurisdiction of the social studies teacher to talk about the relationships between established churches and science, in this case between Galileo and the Catholic church, or between Copernicus and many Protestants. S/he can then link back to science and society, pointing out how much scientific exploration is tied to prevailing social attitudes; and this message will be further expanded as the year progresses in both science and history classes.
This theme can also be incorporated into the English or reading classes. Students in the middle school are often offered books dealing with children in transition; these are issues to which they can easily relate. In return, they frequently write about this subject as well. It would be simple to create a reading and writing assignment where students are asked to contrast their thought processes now with the way they thought when they were younger; and to compare this with the ways in which the study of science itself changed between Aristotle's and Newton's times. If a writing assignment within the science class is desired (and it should be), the student could be asked to imagine that s/he was a scientist in Galileo's time: which of the many differing views would s/he support, given the available evidence?
Exercises such as these are invaluable tools for teaching the philosophy of science, as well as being practical examples of the application of scientific thought. They provide the student with a sense of connection to past discoveries and discoverers, a link between their growing minds and the growth of scientific knowledge. Clearly, historical relationships are a nice addition to the science classroom... but are they necessary?
Science for all Americans: AAAS Goals for Science Education
New Hampshire and many other states are now in the process of adopting the broad goals for science education described in the American Association for the Advancement of Science's "Project 2061," which is aimed at improving the scientific literacy of the American citizenry. Among its more obvious goals of increasing the use of problem solving strategies, demonstrating an understanding of basic natural laws, and the like, are goals that are historical in nature. The New Hampshire version includes the following broad goals related to history:
1 ) Students will perceive that scientific knowledge is the result of the cumulative efforts of people, past and present, who have attempted to explain the world through an objective, peer-tested, rational approach to understanding natural phenomena and occurances.
2 ) Students will demonstrate an understanding of the impact of science and technology on society.
In its segment on "Science as Inquiry," the New Hampshire standards reads, in part: The knowledge base in science has evolved over a long peropd of time. There have been great scientists who are recognized primarily for the development of major theories which connected a large body of previously unrelated experimental evidence, causing us to consider natural phenomena in a new light, e.g. Copernicus, Newton, Darwin, Einstein, and Watson/Crick. Although the more abstract ideas which have evolved in the history and philosophy of science are beyond young students' complete understanding, they are able to consider and understand critical events which led to the development or modifications of scientific theories. This knowledge can lead to a deeper and greater understanding of the laws governing the universe during their adult years. Proficiency standards include:
3 ) By the end of grade six, students will be able to seek information for comparing past and present scientific ideas and theories.
4) By the end of grade ten, students will be able to: compare and contrast how technology has shaped our lives both in the past and the present; demonstrate an understanding that science knowledge has, over time, accumulated most rapidly after acceptance of major new theories.
The "Science, Technology, and Society" portion likewise recognizes the importance of the history of science, stating that judicial use of case studies from the history of science can help students to more completely understand the ongoing interaction between the scientific community and the wider society, and that access to the most recent technological tools will be a distinct advantage to teachers and students as they work to identify and understand the economic, social, and ethical aspects of historical and contemporary scientific issues and solutions. Proficiency standards highlight the use of examples from history which can serve as illustrations of the effects of scientific knowledge on society.
Students today, like their peers in the past, face a world that is changing rapidly, and whose technology often pushes it into directions that no one could ever have predicted. Yet it is inevitably true that "those who forget the past are doomed to repeat it," and this is also the case with the history of science: we can learn many things from the ways in which science has affected the lives of those who came before us. If we are careful to teach the citizens of the future the lessons revealed in the last century, when the Industrial Revolution irrevocably altered the lives of those who followed; and in the Enlightenment, when new breakthroughs rocked the formerly invariable philosophies of church and science alike, then perhaps we can lessen the negative impacts that new technologies and discoveries inevitably have on society. The new information technologies make it easier than ever before; state education boards have begun to mandate it; and the integrity of our children's schooling depends on it. We would clearly be remiss to neglect the integration of science and history; that is something that this future teacher will avoid at all costs.
Sources Cited
American Association for the Advancement of Science, Science for All Americans: Project 2061 (1989) ó Broad Goals for Science Education
Brush, L. (1979) Avoidance of science and stereotypes of scientists. Journal of Research in Science Teaching. 16, 237-241
Butterfield, Herbert. The Origins of Modern Science (Revised edition)
Copyright 1957 by G. Bell & Sons Ltd. New York, NY
Hodson, Derek (1991) Philosophy of Science and Science Education. in History, Philosophy, and Science Teaching Michael Matthews (ed), 19-32.
"Understanding Basic Scientific and Technical Concepts," from the National Science Board's Science and Engineering Indicators (published by U.S. Government Printing Office)