This article addresses and attempts to refute several of the most
widespread and enduring misconceptions held by students regarding the
enterprise of science. The ten myths discussed include the common notions
that theories become laws, that hypotheses are best characterized as
educated guesses, and that there is a commonly-applied scientific method.
In addition, the article includes discussion of other incorrect ideas such
as the view that evidence leads to sure knowledge, that science and its
methods provide absolute proof, and that science is not a creative
endeavor. Finally, the myths that scientists are objective, that
experiments are the sole route to scientific knowledge and that scientific
conclusions are continually reviewed conclude this presentation. The paper
ends with a plea that instruction in and opportunities to experience the
nature of science are vital in preservice and inservice teacher education
programs to help unseat the myths of science.
Myths are typically defined as traditional views, fables, legends or
stories. As such, myths can be entertaining and even educational since
they help people make sense of the world. In fact, the explanatory role of
myths most likely accounts for their development, spread and persistence.
However, when fact and fiction blur, myths lose their entertainment value
and serve only to block full understanding. Such is the case with the
myths of science.
Scholar Joseph Campbell (1968) has proposed that the similarity among many
folk myths worldwide is due to a subconscious link between all peoples,
but no such link can explain the myths of science. Misconceptions about
science are most likely due to the lack of philosophy of science content
in teacher education programs, the failure of such programs to provide and
require authentic science experiences for preservice teachers and the
generally shallow treatment of the nature of science in the precollege
textbooks to which teachers might turn for guidance.
As Steven Jay Gould points out in The Case of the Creeping Fox Terrier
Clone (1988), science textbook writers are among the most egregious
purveyors of myth and inaccuracy. The fox terrier mentioned in the title
refers to the classic comparison used to express the size of the dawn
horse, the tiny precursor to the modem horse. This comparison is
unfortunate for two reasons. Not only was this horse ancestor much bigger
than a fox terrier, but the fox terrier breed of dog is virtually unknown
to American students. The major criticism leveled by Gould is that once
this comparison took hold, no one bothered to check its validity or
utility. Through time, one author after another simply repeated the inept
comparison and continued a tradition that has made many science texts
virtual clones of each other on this and countless other points.
In an attempt to provide a more realistic view of science and point out
issues on which science teachers should focus, this article presents and
discusses 10 widely-held, yet incorrect ideas about the nature of science.
There is no implication that all students, or most teachers for that
matter, hold all of these views to be true, nor is the list meant to be
the definitive catolog. Cole (1986) and Rothman (1992) have suggested
additional misconceptions worthy of consideration. However, years of
science teaching and the review of countless texts has substantiated the
validity of the inventory presented here.
Myth 1: Hypotheses Become Theories Which Become Laws
This myth deals with the general belief that with increased evidence there
is a developmental sequence through which scientific ideas pass on their
way to final acceptance. Many believe that scientific ideas pass through
the hypothesis and theory stages and finally mature as laws. A former U.S.
president showed his misunderstanding of science by saying that he was not
troubled by the idea of evolution because it was "just a theory." The
president's misstatement is the essence of this myth; that an idea is not
worthy of consideration until "lawness" has been bestowed upon it.
The problem created by the false hierarchical nature inherent in this myth
is that theories and laws are very different kinds of knowledge. Of course
there is a relationship between laws and theories, but one simply does not
become the other--no matter how much empirical evidence is amassed. Laws
are generalizations, principles or patterns in nature and theories are the
explanations of those generalizations (Rhodes & Schaible, 1989; Homer &
Rubba, 1979; Campbell, 1953).
For instance, Newton described the relationship of mass and distance to
gravitational attraction between objects with such precision that we can
use the law of gravity to plan spaceflights. During the Apollo 8 mission,
astronaut Bill Anders responded to the question of who was flying the
spacecraft by saying, "I think that Issac Newton is doing most of the
driving fight now." (Chaikin, 1994, p. 127). His response was understood
by all to mean that the capsule was simply following the basic laws of
physics described by Isaac Newton years centuries earlier.
The more thorny, and many would say more interesting, issue with respect
to gravity is the explanation for why the law operates as it does. At this
point, there is no well. accepted theory of gravity. Some physicists
suggest that gravity waves are the correct explanation for the law of
gravity, but with clear confirmation and consensus lacking, most feel that
the theory of gravity still eludes science. Interestingly, Newton
addressed the distinction between law and theory with respect to gravity.
Although he had discovered the law of gravity, he refrained from
speculating publically about its cause. In Principial, Newton states" . .
. I have not been able to discover the cause of those properties of
gravity from phenomena, and I frame no hypothesis . . ." " . . . it is
enough that gravity does really exist, and act according to the laws which
we have explained . . ." (Newton, 1720/1946, p. 547).
Myth 2: A Hypothesis is an Educated Guess
The definition of the term hypothesis has taken on an almost mantra- like
life of its own in science classes. If a hypothesis is always an educated
guess as students typically assert, the question remains, "an educated
guess about what?" The best answer for this question must be, that without
a clear view of the context in which the term is used, it is impossible to
tell.
The term hypothesis has at least three definitions, and for that reason,
should be abandoned, or at least used with caution. For instance, when
Newton said that he framed no hypothesis as to the cause of gravity he was
saying that he had no speculation about an explanation of why the law of
gravity operates as it does. In this case, Newton used the term hypothesis
to represent an immature theory.
As a solution to the hypothesis problem, Sonleitner (1989) suggested that
tentative or trial laws be called generalizing hypotheses with provisional
theories referred to as explanatory hypotheses. Another approach would be
to abandon the word hypothesis altogether in favor of terms such as
speculative law or speculative theory. With evidence, generalizing
hypotheses may become laws and speculative theories become theories, but
under no circumstances do theories become laws. Finally, when students are
asked to propose a hypothesis during a laboratory experience, the term now
means a prediction. As for those hypotheses that are really forecasts,
perhaps they should simply be called what they are, predictions.
Myth 3: A General and Universal Scientific Method Exists
The notion that a common series of steps is followed by all research
scientists must be among the most pervasive myths of science given the
appearance of such a list in the introductory chapters of many precollege
science texts. This myth has been part of the folklore of school science
ever since its proposal by statistician Karl Pearson (1937). The steps
listed for the scientific method vary from text to text but usually
include, a) define the problem, b) gather background information, c) form
a hypothesis, d) make observations, e) test the hypothesis, and f) draw
conclusions. Some texts conclude their list of the steps of the scientific
method by listing communication of results as the final ingredient.
One of the reasons for the widespread belief in a general scientific
method may be the way in which results are presented for publication in
research journals. The standardized style makes it appear that scientists
follow a standard research plan. Medawar (1990) reacted to the common
style exhibited by research papers by calling the scientific paper a fraud
since the final journal report rarely outlines the actual way in which the
problem was investigated.
Philosophers of science who have studied scientists at work have shown
that no research method is applied universally (Carey, 1994; Gibbs &
Lawson, 1992; Chalmers, 1990; Gjertsen, 1989). The notion of a single
scientific method is so pervasive it seems certain that many students must
be disappointed when they discover that scientists do not have a framed
copy of the steps of the scientific method posted high above each
laboratory workbench.
Close inspection will reveal that scientists approach and solve problems
with imagination, creativity, prior knowledge and perseverance. These, of
course, are the same methods used by all problem-solvers. The lesson to be
learned is that science is no different from other human endeavors when
puzzles are investigated. Fortunately, this is one myth that may
eventually be displaced since many newer texts are abandoning or
augmenting the list in favor of discussions of methods of science.
Myth 4: Evidence Accumulated Carefully Will Result in Sure Knowledge
All investigators, including scientists, collect and interpret empirical
evidence through the process called induction. This is a technique by
which individual pieces of evidence are collected and examined until a law
is discovered or a theory is invented. Useful as this technique is, even a
preponderance of evidence does not guarantee the production of valid
knowledge because of what is called the problem of induction.
Induction was first formalized by Frances Bacon in the 17th century. In
his book, Novum Organum (1620/ 1952), Bacon advised that facts be
assimilated without bias to reach a conclusion. The method of induction he
suggested is the principal way in which humans traditionally have produced
generalizations that permit predictions. What then is the problem with
induction?
It is both impossible to make all observations pertaining to a given
situation and illogical to secure all relevant facts for all time, past,
present and future. However, only by making all relevant observations
throughout all time, could one say that a final valid conclusion had been
made. This is the problem of induction. On a personal level, this problem
is of little consequence, but in science the problem is significant.
Scientists formulate laws and theories that are supposed to hold true in
all places and for all time but the problem of induction makes such a
guarantee impossible.
The proposal of a new law begins through induction as facts are heaped
upon other relevant facts. Deduction is useful in checking the validity of
a law. For example, if we postulate that all swans are white, we can
evaluate the law by predicting that the next swan found will also be
white. If it is, the law is supported, but not proved as will be seen in
the discussion of another science myth. Locating even a single black swan
will cause the law to be called into question.
The nature of induction itself is another interesting aspect associated
with this myth. If we set aside the problem of induction momentarily,
there is still the issue of how scientists make the final leap from the
mass of evidence to the conclusion. In an idealized view of induction, the
accumulated evidence will simply result in the production of a new law or
theory in a procedural or mechanical fashion. In reality, there is no such
method. The issue is far more complex -- and interesting --than that. The
final creative leap from evidence to scientific knowledge is the focus of
another myth of science.
Myth 5: Science and its Methods Provide Absolute Proof
The general success of the scientific endeavor suggests that its products
must be valid. However, a hallmark of scientific knowledge is that it is
subject to revision when new information is presented. Tentativeness is
one of the points that differentiates science from other forms of
knowledge. Accumulated evidence can provide support, validation and
substantiation for a law or theory, but will never prove those laws and
theories to be true. This idea has been addressed by Homer and Rubba
(1978) and Lopnshinsky (1993).
The problem of induction argues against proof in science, but there is
another element of this myth worth exploring. In actuality, the only truly
conclusive knowledge produced by science results when a notion is
falsified. What this means is that no matter what scientific idea is
considered, once evidence begins to accumulate, at least we know that the
notion is untrue. Consider the example of the white swans discussed
earlier. One could search the world and see only white swans, and arrive
at the generalization that "all swans are white. " However, the discovery
of one black swan has the potential to overturn, or at least result in
modifications of, this proposed law of nature. However, whether scientists
routinely try to falsify their notions and how much contrary evidence it
takes for a scientist's mind to change are issues worth exploring.
Myth 6: Science Is Procedural More Than Creative
We accept that no single guaranteed method of science can account for the
success of science, but realize that induction, the collection and
interpretation of individual facts providing the raw materials for laws
and theories, is at the foundation of most scientific endeavors. This
awareness brings with it a paradox. If induction itself is not a
guaranteed method for arriving at conclusions, how do scientists develop
useful laws and theories?
Induction makes use of individual facts that are collected, analyzed and
examined. Some observers may perceive a pattern in these data and propose
a law in response, but there is no logical or procedural method by which
the pattern is suggested. With a theory, the issue is much the same. Only
the creativity of the individual scientist permits the discovery of laws
and the invention of theories. If there truly was a single scientific
method, two individuals with the same expertise could review the same
facts and reach identical conclusions. There is no guarantee of this
because the range and nature of creativity is a personal attribute.
Unfortunately, many common science teaching orientations and methods serve
to work against the creative element in science. The majority of
laboratory exercises, for instance, are verification activities. The
teacher discusses what will happen in the laboratory, the manual provides
step-by-step directions, and the student is expected to arrive at a
particular answer. Not only is this approach the antithesis of the way in
which science actually operates, but such a portrayal must seem dry,
clinical and uninteresting to many students. In her book, They're Not
Dumb, They're Different (1990) Shiela Tobias argues that many capable and
clever students reject science as a career because they are not given an
opportunity to see it as an exciting and creative pursuit. The moral in
Tobias' thesis is that science itself may be impoverished when students
who feel a need for a creative outlet eliminate it as a potential career
because of the way it is taught.
Myth 7: Science and its Methods Can Answer All Questions.
Philosophers of science have found it useful to refer to the work of Karl
Popper (1968) and his principle of falsifiability to provide an
operational definition of science. Popper believed that only those ideas
that are potentially falsifiable are scientific ideas.
For instance, the law of gravity states that more massive objects exert a
stronger gravitational attraction than do objects with less mass when
distance is held constant. This is a scientific law because it could be
falsified if newly-discovered objects operate differently with respect to
gravitational attraction. In contrast, the core idea among creationists is
that species were placed on earth fully-formed by some supernatural
entity. Obviously, there is no scientific method by which such a belief
could be shown to be false. Since this special creation view is impossible
to falsify, it is not science at all and the term creation science is an
oxymoron. Creation science is a religious belief and as such, does not
require that it be falsifiable. Hundreds of years ago thoughtful
theologians and scientists carved out their spheres of influence and have
since coexisted with little acrimony. Today, only those who fail to
understand the distinction between science and religion confuse the rules,
roles, and limitations of these two important world views.
It should now be clear that some questions simply must not be asked of
scientists. During a recent creation science trial for instance, Nobel
laureates were asked to sign a statement about the nature of science to
provide some guidance to the court. These famous scientists responded
resoundingly to support such a statement; after all they were experts in
the realm of science (Klayman, Slocombe, Lehman, & Kaufman, 1986). Later,
those interested in citing expert opinion in the abortion debate asked
scientists to issue a statement regarding their feelings on this issue.
Wisely, few participated. Science cannot answer the moral and ethical
questions engendered by the matter of abortion. Of course, scientists as
individuals have personal opinions about many issues, but as a group, they
must remain silent if those issues are outside the realm of scientific
inquiry. Science simply cannot address moral, ethical, aesthetic, social
and metaphysical questions.
Myth 8. Scientists are Particularly Objective
Scientists are no different in their level of objectivity than are other
professionals. They are careful in the analysis of evidence and in the
procedures applied to arrive at conclusions. With this admission, it may
seem that this myth is valid, but contributions from both the philosophy
of science and psychology reveal that there are at least three major
reasons that make complete objectivity impossible.
Many philosophers of science support Popper's (1963) view that science can
advance only through a string of what he called conjectures and
refutations. In other words, scientists should propose laws and theories
as conjectures and then actively work to disprove or refute those ideas.
Popper suggests that the absence of contrary evidence, demonstrated
through an active program of refutation, will provide the best support
available. It may seem like a strange way of thinking about verification,
but the absence of disproof is considered support. There is one major
problem with the idea of conjecture and refutation. Popper seems to have
proposed it as a recommendation for scientists, not as a description of
what scientists do. From a philosophical perspective the idea is sound,
but there are no indications that scientists actively practice programs to
search for disconfirming evidence.
Another aspect of the inability of scientists to be objective is found in
theory-laden observation, a psychological notion (Hodson, 1986).
Scientists, like all observers, hold a myriad of preconceptions and biases
about the way the world operates. These notions, held in the subconscious,
affect everyone's ability to make observations. It is impossible to
collect and interpret facts without any bias. There have been countless
cases in the history of science in which scientists have failed to include
particular observations in their final analyses of phenomena. This occurs,
not because of fraud or deceit, but because of the prior knowledge
possessed by the individual. Certain facts either were not seen at all or
were deemed unimportant based on the scientists's prior knowledge. In
earlier discussions of induction, we postulated that two individuals
reviewing the same data would not be expected to reach the same
conclusions. Not only does individual creativity play a role, but the
issue of personal theory-laden observation further complicates the
situation.
This lesson has clear implications for science teaching. Teachers
typically provide learning experiences for students without considering
their prior knowledge. In the laboratory, for instance, students are asked
to perform activities, make observations and then form conclusions. There
is an expectation that the conclusions formed will be both self-evident
and uniform. In other words, teachers anticipate that the data will lead
all pupils to the same conclusion. This could only happen if each student
had the same exact prior conceptions and made and evaluated observations
using identical schemes. This does not happen in science nor does it occur
in the science classroom.
Related to the issue of theory-based observations is the allegiance to the
paradigm. Thomas Kuhn (1970), in his ground-breaking analysis of the
history of science, shows that scientists work within a research tradition
called a paradigm. This research tradition, shared by those working in a
given discipline, provides clues to the questions worth investigating,
dictates what evidence is admissible and prescribes the tests and
techniques that are reasonable. Although the paradigm provides direction
to the research it may also stifle or limit investigation. Anything that
confines the research endeavor necessarily limits objectivity. While there
is no conscious desire on the part of scientists to limit discussion, it
is likely that some new ideas in science are rejected because of the
paradigm issue. When research reports are submitted for publication they
are reviewed by other members of the discipline. Ideas from outside the
paradigm are liable to be eliminated from consideration as crackpot or
poor science and thus do not appear in print.
Examples of scientific ideas that were originally rejected because they
fell outside the accepted paradigm include the sun-centered solar system,
warm-bloodedness in dinosaurs, the germ-theory of disease, and continental
drift. When first proposed early in this century by Alfred Wegener, the
idea of moving continents, for example, was vigorously rejected.
Scientists were not ready to embrace a notion so contrary to the
traditional teachings of their discipline. Continental drift was finally
accepted in the 1960s with the proposal of a mechanism or theory to
explain how continental plates move (Hallam, 1975 and Menard, 1986). This
fundamental change in the earth sciences, called a revolution by Kuhn,
might have occurred decades earlier had it not been for the strength of
the paradigm.
It would be unwise to conclude a discussion of scientific paradigms on a
negative note. Although the examples provided do show the contrary aspects
associated with paradigm-fixity, Kuhn would argue that the blinders
created by allegiance to the paradigm help keep scientists on track. His
review of the history of science demonstrates that paradigms are
responsible for far more successes in science than delays.
Myth 9: Experiments are the Principle Route to Scientific Knowledge
Throughout their school science careers, students are encouraged to
associate science with experimentation. Virtually all hands-on experiences
that students have in science class is called experiments even if it would
be more accurate to refer to these exercises as technical procedures,
explorations or activities. True experiments involve carefully
orchestrated procedures along with control and test groups usually with
the goal of establishing a cause and effect relationship. Of course, true
experimentation is a useful tool in science, but is not the sole route to
knowledge.
Many note-worthy scientists have used non-experimental techniques to
advance knowledge. In fact, in a number of science disciplines, true
experimentation is not possible because of the inability to control
variables. Many fundamental discoveries in astronomy are based on
extensive observations rather than experiments. Copernicus and Kepler
changed our view of the solar system using observational evidence derived
from lengthy and detailed observations frequently contributed by other
scientists, but neither performed experiments.
Charles Darwin punctuated his career with an investigatory regime more
similar to qualitative techniques used in the social sciences than the
experimental techniques commonly associated with the natural sciences.
For his most revolutionary discoveries, Darwin recorded his extensive
observations in notebooks annotated by speculations and thoughts about
those observations. Although Darwin supported the inductive method
proposed by Bacon, he was aware that observation without speculation or
prior understanding was both ineffective and impossible. The techniques
advanced by Darwin have been widely used by scientists Goodall and Nossey
in their primate studies. Scientific knowledge is gained in a variety of
ways including observation, analysis, speculation, library investigation
and experimentation.
Myth 10: All Work in Science is Reviewed to Keep the Process Honest.
Frequently, the final step in the traditional scientific method is that
researchers communicate their results so that others may learn from and
evaluate their research. When completing laboratory reports, students are
frequently told to present their methods section so clearly that others
could repeat the activity. The conclusion that students will likely draw
from this request is that professional scientists are also constantly
reviewing each other's experiments to check up on each other.
Unfortunately, while such a check and balance system would be useful, the
number of findings from one scientist checked by others is vanishingly
small In reality, most scientists are simply too busy and research funds
too limited for this type of review.
The result of the lack of oversight has recently put science itself under
suspicion. With the pressures of academic tenure, personal competition and
funding, it is not surprising that instances of outright scientific fraud
do occur. However, even without fraud, the enormous amount of original
scientific research published, and the pressure to produce new information
rather than reproduce others' work dramatically increases the chance that
errors will go unnoticed.
An interesting corollary to this myth is that scientists rarely report
valid, but negative results. While this is understandable given the space
limitations in scientific journals, the failure to report what did not
work is a problem. Only when those working in a particular scientific
discipline have access to all of the information regarding a phenomenon --
both positive and negative -- can the discipline progress.
American Association for the Advancement of Science (1993). Benchmarks for
science literacy. New York: Oxford University Press.
Bacon, F. (1952). The new organon. In R. M. Hutchins, (Ed.), Great Books
of the Western World: Vol. 30. The Works of Francis Bacon (pp. 107-195)
Chicago: Encyclopedia Britannica, Inc. (Original work published in 1620).
Campbell, N. (1953). What is science? New York: Dover Publications.
Campbell, J. (1968). The hero with a thousand faces. Princeton, NJ:
Princeton University Press.
Carey, S. S. (1994). A beginners guide to scientific method Belmont, CA:
Wadsworth Publishing Company.
Chaikin, A. (1994). A man on the moon: The voyages of the Apollo
astronauts. New York: Viking Press.
Chalmers, A. (1990). Science and its fabrication. Minneapolis, MN:
University of Minnesota Press.
Cole, K.C. (1986, March 23). Things your teacher never told you about
science: Nine shocking revelations! The Newsday Magazine, 21-27.
Gibbs, A. and Lawson, A. E. (1992). The nature of scientific thinking as
reflected by the work of biologists and by biology textbooks. American
Biology Teacher, 54 (3), 137-152.
Gjertsen, D. (1989). Science and philosophy past and present. New York:
Penguin Books.
Gould, S. J. (1988). The case of the creeping fox terrier clone. Natural
History, 96(1), 16-24.
Hallam, A. (1975). Alfred Wegener and the hypothesis of continental drift.
Scientific American, 252(2), 88-97.
Hodson, D. (1986). The mature of scientific observation. School Science
Review, 58(242), 17-28.
Horner, J. K. & Rubba, P. A. (1979) The laws are mature theories fable.
The Science Teacher,46(2), 31.
Horner, J. K. & Rubba, P. A. (1978) The myth of absolute truth. The
Science Teacher, 45(1), 29-30.
Klayman, R. A., Slocombe, W. B., Lehman, J. S. and Kaufman, B.S. (1986).
Amicus curiae brief of 72 Nobel laureates, 17 state academies of science,
and 7 other scientific organizations, in support of appellees. Edwards v.
Aguillard, 85 U.S. 1513.
Kuhn, T. S. (1970). The structure of scientific revolutions, (2nd ed.).
Chicago: University of Chicago Press.
Lopushinsky, T. (1993). Does science deal in truth? The Journal of College
Science Teaching, 23(3), 208.
Medawar. P. B. (1963). Is the scientific paper a fraud? In P. B. Medawar.
The Threat and the Glory. (pp. 228-233). New York: HarperCollins.
Menard, H. W. (1986). The ocean of truth: A personal history of global
tectonics. Princeton, NJ: Princeton University Press.
National Research Council (1994). National science education standards
(Draft). Washington, DC: Author.
Newton, I. (1946). Sir Isaac Newton's mathematical principles of natural
philosophy and his system of the world. (A. Motte, Transl. revised and
appendix supplied by F. Cajori). Berkeley, CA: University of California
Press. (Original work published in 1720).
Pearson,. K. (1937). The grammar of science. London: Dutton.
Popper, K. R. (1968). The logic of scientific discovery, (2nd ed.
revised). New York: Harper Torchbooks.
Popper, K. R. (1963). Conjectures and refutations: The growth of
scientific knowledge. New York: Harper and Row.
Rhodes, G. and Schaible (1989). Fact, law, and theory: Ways of thinking in
science and literature. Journal of College Science Teaching, 18(4),
228-232 & 288.
Rothman, M. A. (1992). The science gap. Buffalo: Prometheus Books.
Sonleitner, F. J. (1989, Nov/Dec). Theories, laws and all that. National
Center for Science Education, Newsletter, 9(6), 3-4.
Tobias, S. (1990). They're not dumb, they're different: Stalking the
second tier. Tucson, AZ: The Research Corporation.
.