Nature of Science 1
NATURE OF SCIENTIFIC KNOWLEDGE AND SCIENTIFIC METHODOLOGY.
(This text is adapted from first chapter of “Science for all Americans. Project 2061 of American Association for the
Advancement of Science. (1990) Oxford University Press. New York, NY.)
Over the course of history, we have attempted to understand ourselves, our environment, and our
role in the environment. To do so we use different “ways of knowing about our world including
scientific knowledge, societal knowledge, religious knowledge, and cultural knowledge. Science
differs from these other ways of knowing in important ways.”(2)
Science is a way of knowing about the physical and biological worlds. “People have developed
many interconnected and validated ideas about these worlds. Those ideas have enabled
successive generations of humans to achieve an increasingly comprehensive and reliable
understanding of the human species and its environment. The means used to develop these ideas
are particular ways of observing, thinking, experimenting, and validating. These ways represent a
fundamental aspect of the nature of science and reflect how science tends to differ from other
modes of knowing.”(1)
This chapter on the Nature of Science focuses on three areas: the scientific world view, the
scientific method, and the nature of the scientific enterprise. [The numbered statements printed
in italics are the specific ‘Nature-of-Science’ objectives of the Natural World LADR.]
THE SCIENTIFIC WORLD VIEW.
Science is a way of knowing of ourselves and of the world (universe) in which we live. This is,
we can understand or explain how the many functions of our body and environment work (e.g.,
the blood circulates because the heart pumps the blood around, predict the movement of earth,
planets, and sun, and can predict the inheritance of genes, or explain how genetic material is
carefully divided over to daughter cells during cellular reproduction.) We express our knowledge
or understanding of a function or activity by describing the underlying mechanism. When our
understanding involves very fundamental areas of our bodies or of the universe our knowledge is
set out in theories (e.g., the theory of plate tectonics, the relativity theory, and the evolution
theory) or is summarized in laws (e.g., law of gravity, law of thermodynamics) or dogma e.g.,
the central dogma in molecular biology).
Note that in science a theory is a very fundamental explanation that affects a wide range of
aspects of the world. Also, the meaning of the word theory in science (a body of knowledge
that explains with considerable certainty large sets of activities of the world. A theory is
held with a high degree of confidence and is supported by enough evidence to make its
abandonment unlikely) is different from that of the vernacular English usage(one of several
speculative explanations of an activity, that is, a hunch or a guess). Similarly, scientists use
the word “dogma” (a summary statement of a very fundamental understanding of the
world) differently from its vernacular usage (an immutable truth).
Examples of scientific theories (2):
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(a) Atomic theory: The atom is the smallest unit of matter. The atom is composed of the
nucleus in the middle of the atom that is composed of neutrons, protons, (both of these
may break down in smaller particles). The neutrons have no charge. The protons have a
positive charge. The electrons swirl around the nucleus in a large region, rather than
orbiting in affixed pattern (electron cloud). The electrons have a negative charge.
(b) Big Bang theory: The Big Bang Theory assumes that the universe began from a singular
state of infinite density and started expanding from an explosive moment of creation. The
theory was further developed in the 1940s by George Gamow and R.A. Alpher. Fred
Hoyle coined the term Big Bang. The Big Bang theory is the dominant scientific theory
about the origin of the universe. According to the theory, the universe was created
sometime between 10 billion and 20 billion years ago from a cosmic explosion that
hurled matter in all directions.
(c) Gravity theory: Gravity is a force that attracts objects in the universe. The most familiar
of the four fundamental interactions of matter, gravitation has several characteristics that
distinguish it from the other interactions. (1) It is universal, (2) it is always attractive, (3)
it is a long-range interaction, and (4) it affects all matter.
(d) Evolution theory: Evolution theory states that all living things are related to one another
through common ancestry from earlier forms that differed from the present form.
Biologists agree that all living things arose through a long history of changes shaped by
physical, chemical processes that are still taking place. Variability among individuals of a
population of sexually reproducing organisms is produced by mutation and genetic
recombination. The resulting genetic variability is subject to natural selection in the
environment.
(e) Cell theory: (1) All living material is organized in cells. (2) All cells are derived from
previously existing cells (most cells arise by cell division, but in sexual organisms they
may be formed by the fusion of gametes. (3) The cell is the most elementary unit of life.
Every cell is bound by a plasma membrane that separates it from the environment and
from other cells.
(f) Germ theory of Disease: Louis Pasteur argued that infectious diseases are caused by
germs. The germ theory has affected our views on infectious diseases, surgery, hospital
management, agriculture, and industry.
(g) Special Relativity theory. Albert Einstein’s theory of Special Relativity, published 1905,
revealed that energy and matter are different manifestations of the same phenomenon and
can be transformed into each other in terms of the relationship E=mc2.
(h) General Relativity Theory. Einstein’s General Relativity Theory (1917) provided a
powerful new way to view gravity as a warping of the four-dimensional space-time
continuum by the presence of matter. If space-time is imagined as a rubber sheet, then
massive objects such as stars and galaxies create deformations in space-time, just as a
bowling bowl sitting on a mattress creates a dent into which nearby smaller objects fall.
Thus the shape of space-time determines the behavior of matter/energy. At the same time,
the presence of matter/energy determines the shape of space-time.
(i) Plate Tectonics theory: Plate tectonics is an all-embracing theory that the crust of the
earth is divided into a number of rigid plates floating on a viscous underlayer of the
mantle. Alfred L. Wegener was the first to propose (1912) that the continents were at one
time connected and had drifted apart. In 1960 when H. H. Hess suggested that new ocean
floor was created at the mid-oceanic ridges and the ocean evolved by seafloor spreading.
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(j) Quantum Theory: This theory says that energy exist in tiny discrete units called quanta.
Quantum theory shows how atomic particles such as electrons may also be seen as having
wave-like properties. Quantum theory is the basis of particle physics, modern theoretical
chemistry, and the solid-state physics that describes the behavior of the silicon chips used
in computers. Quantum theory and the theory of relativity together form the theoretical
basis of modern physics. Later work by scientists elaborated the theory into what is called
quantum mechanics (or wave mechanics).
(k) Unified Field Theory: This theory proposes to unify the four known interactions or forces
(the strong, electromagnetic, weak, and gravitational forces) by a simple set of general
laws. These four forces control all the observed interactions in matter: gravitation,
electromagnetism, the strong force tat holds atomic nuclei together, and the weak force
(force present in some nuclear processes).
The world is understandable:
In its attempt to understand the world, science assumes (a) the existence of an external reality
(the world or the universe), and (b) the uniformity of nature, i.e., that natural processes operate in
a fairly consistent manner (this is the basis for the idea of natural laws). (3) Thus, science
assumes that the world (universe) around us is real and independent of human perception
(philosophers use the word objective) and that we can know that reality, i.e., that it is not part of
or colored by our individual imaginations. (Note that not all philosophers of science agree with
this last assumption.)
“Secondly, science presumes that the things and events in the universe occur in consistent
patterns that are comprehensible through careful, systematic study. Scientists believe that
through the use of the intellect, and with the aid of instruments that extend the senses, people can
discover patterns in all of nature.”(1) Thus, the testimonial of Leon Lederman (Director emeritus
of Fermi National Accelerator Laboratory) in the closing words of his essay: “And underlying it
all, the sense of wonder that nature is comprehensible.” (5)
“Science assumes that the universe is, as its name implies, a vast single system in which the
basic rules are everywhere the same. Knowledge gained from studying one part of the universe is
applicable to other parts. For instance, the same principles of motion and gravitation that explain
the motion of falling objects on the surface of the earth also explain the motion of the moon and
the planets. With some modifications over the years, the same principles of motion have applied
to other forces – and to the motion of everything, from the smallest nuclear particles to the most
massive stars, from sailboats to space vehicles, from bullets to light rays.”(1)
The tools used to discover the consistent patterns of nature form the scientific method. You will
learn more about this in the second leg of this chapter.
1. Articulate a central assumption of science: the universe is real and operates according to
universally consistent rules, and we can discover these rules by logical thought subject to
test through experiments and observations.
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Scientific ideas are subject to change:
“Science is a process for producing knowledge. The process depends both on making careful
observations of phenomena (these include the results of experiments) and on inventing theories
(constructing models) for making sense out of those observations. Change in knowledge is
inevitable because new observations may challenge prevailing theories. No matter how well one
theory explains a set of observations, it is possible that another theory may fit just as well or
better, or may fit a still wider range of observations. In science, the testing and improving and
occasional discarding of theories, whether new or old, go on all the time. Scientists assume that
even if there is no way to secure complete and absolute truth, increasingly accurate
approximations can be made to account for the world and how it works.”(1).
2. Explain why no scientific knowledge is considered to be absolutely and completely true,
and be able to give examples of how science has historically improved, discarded, and
replaced theories by experiments and observations.
Scientific knowledge is durable:
The idea that scientific knowledge is subject to change may lead to the suggestion that we never
know anything (with any certainty). That is, the knowledge that we have of ourselves and our
world is, at best, very tentative, and is likely going to change as new information or knowledge
emerges. Of course, this is not correct. Quite a bit of what we have learned in the physical and
biological sciences has ‘stood the test of time’ and is ‘known’. Moreover, it has been the basis of
our ever expanding understanding of the universe.
“Although scientists reject the notion of attaining absolute truth and accept some uncertainty as
part of nature, most scientific knowledge is durable. The modification of ideas, rather than their
outright rejection, is the norm in science, as powerful constructs tend to survive and grow more
precise and to become widely accepted. For example, in formulating the theory of relativity,
Albert Einstein did not discard the Newtonian laws of motion but rather showed them to be only
an approximation of limited application within a more general concept. (NASA uses Newtonian
mechanics, for instance, in calculating satellite trajectories.) Moreover, the growing ability of
scientists to make accurate predictions about natural phenomena provides convincing evidence
that we really are gaining in our understanding of how the world works. Continuity and stability
are as characteristic of science as change is, and confidence is as prevalent as tentativeness.”(1)
Scientists accept that we do not yet have a complete understanding of our world and ourselves
and that we may never reach that complete understanding. However, what we do know or
understand seems to be realistic or relevant to the reality of the natural world. Thus, it seems
clear that the genetic material of all organisms (except RNA viruses) is DNA, that the DNA is a
double-stranded molecule of nucleic acid, etc. As science progresses, we seem to modify existing
models of the reality rather than revolutionizing with entirely new fundamental concepts. Most
modification and changes of our concepts occur at the foreground of science. For example,
whereas few researchers doubt that DNA is the genetic material, models/theories of the function
and interaction of different genes in cellular metabolism are actively changing as new
observations are made and need to be explained.
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Science cannot provide complete answers to all questions:
Most scientists include within the domain of legitimate scientific study everything known to
exist or to happen in the material universe. This leaves many questions, phenomena outside the
scientific domain of inquiry. Those matters that do not deal with the material universe, e.g.,
supernatural, ghosts, spirits, etc. are not part of science (although these matters may be of interest
to scientists). Similarly, those matters that can not be addressed by the tools of scientific inquiry
also can not find understanding/explanation in science (see: Scientific Inquiry).
“There are many matters that cannot usefully be examined in a scientific way. There are, for
instance, beliefs that – by their very nature- cannot be proved or disproved (such as the existence
of supernatural powers and beings, or the true purpose of life. See: Scientific inquiry). In other
cases a scientific approach that may be valid to explain observations is likely to be rejected as
irrelevant by people who hold certain beliefs (such as miracles, fortune-telling, astrology, and
superstition). Nor do scientists have the means to settle issues concerning good and evil
(Answers to these questions must be found in religion, philosophy, cultural ideals and other
systems of beliefs.), although they can sometimes contribute to the discussion of such issues by
identifying the likely consequences of particular actions, which may be helpful in weighing
alternatives.”(1)
How science differs from theology:
“The demarcation between science and theology is perhaps easiest, because scientists do
not invoke the supernatural to explain how the natural world works, and they do not rely
on divine revelation to understand it. When early humans tried to give explanations for
natural phenomena, particularly for disasters, invariably they invoked supernatural beings
and forces, and even today divine revelation is as legitimate a source of truth for many
pious Christians, as is science. Many scientists have religion in the best sense of the
word, but scientists do not invoke supernatural causation or divine revelation.
Another feature of science that distinguishes it from theology is its openness. Religions
are characterized by their relative inviolability; in revealed religions, a difference in
interpretation of even a single word in the revealed founding document may lead to the
origin of a new religion. This contrasts dramatically with the situation in any active field
of science, where one finds different versions of almost any explanation. New conjectures
are made continuously, earlier ones are refuted, and at all times considerable intellectual
diversity exists. Indeed, it is by a Darwinian process of variation and selection in the
formation of testing hypotheses that science advances.” (Ernst Mayer4)
Pseudoscience.
A pseudoscience is set of ideas based on theories put forth as scientific when they are not
scientific. Pseudoscientists claim to base their theories on empirical evidence, and they may even
use some scientific methods, though often their understanding of a controlled experiment is
inadequate. Many pseudoscientists relish being able to point out the consistency of their theories
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with known facts or with predicted consequences, but they do not recognize that such
consistency is not proof of anything. It is a necessary condition but not a sufficient condition that
a good scientific theory be consistent with the facts. A theory which is contradicted by the facts
is obviously not a very good scientific theory, but a theory which is consistent with the facts is
not necessarily a good theory. For example, "the truth of the hypothesis that plague is due to evil
spirits is not established by the correctness of the deduction that you can avoid the disease by
keeping out of the reach of the evil spirits" (Beveridge 1957, 118).
Some pseudoscientific theories are based upon an authoritative text rather than
observation or empirical investigation. Creationists, for example, make observations only
to confirm infallible dogmas, not to discover the truth about the natural world.
Some pseudoscientific theories explain what non-believers cannot even observe, e.g.
orgone energy.
Some can't be tested because they are consistent with every imaginable state of affairs in
the empirical world, e.g., L. Ron Hubbard's engram theory.
Some pseudoscientific theories can't be tested because they are so vague and malleable
that anything relevant can be shoehorned to fit the theory, e.g., the enneagram, iridology,
the theory of multiple personality disorder, the Myers-Briggs Type Indicator®, the
theories behind many New Age psychotherapies, and reflexology.
Some theories have been empirically tested and rather than being confirmed they seem
either to have been falsified or to require numerous ad hoc hypotheses to sustain them,
e.g., astrology, biorhythms, facilitated communication, plant perception, and ESP. Yet,
despite seemingly insurmountable evidence contrary to the theories, adherents won't give
them up.
Some pseudoscientific theories rely on ancient myths and legends rather than on physical
evidence, even when their interpretations of those legends either requires a belief
contrary to the known laws of nature or to established facts, e.g., Velikovsky's, von
Däniken's, and Sitchen's theories.
Some pseudoscientific theories are supported mainly by selective use of anecdotes,
intuition, and examples of confirming instances, e.g., anthropometry, aromatherapy,
craniometry, graphology, metoposcopy, personology, and physiognomy.
Some pseudoscientific theories confuse metaphysical claims with empirical claims, e.g.,
the theories of acupuncture, alchemy, cellular memory, Lysenkoism, naturopathy, reiki,
rolfing, therapeutic touch, and Ayurvedic medicine.
Some pseudoscientific theories not only confuse metaphysical claims with empirical
claims, but they also maintain views that contradict known scientific laws and use ad hoc
hypotheses to explain their belief, e.g., homeopathy.
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3. Explain why many questions and assertions are outside the domain of scientific inquiry.
4. Discriminate between scientific and pseudoscientific explanations of natural phenomena.
SCIENTIFIC INQUIRY.
Many of us have learned that scientific inquiry proceeds by way of “The Scientific Method”, a
method that allows the objective collection and interpretation of data. Thus was born the slogan
that ‘Science is derived from facts’. A similar slogan that summarizes aspects of scientific
inquiry states that ‘science is experiential and experimental’, indicating that the facts science
deals with are experienced by the senses (vision, smell, hearing, touch and taste) and are derived
from experiments. Other descriptions of science emphasized the ability to conclusively proof or
falsify hypotheses as key characteristics of the scientific method.
“Scientific inquiry is not easily described apart from the context of particular investigations.
There simply is no fixed set of steps that scientists always follow, no one path that leads them
unerringly to scientific knowledge. There are, however, certain features of science that give it a
distinctive character as a mode of inquiry. Although those features are especially characteristic of
the work of professional scientists, everyone can exercise them in thinking scientifically about
matters of interest in everyday life.”(1)
5. Recognize that there is no single scientific method; that the scientific enterprise consists
of multiple methods and tools of investigation for evaluating ideas.
6. Understand that scientific inquiry is not formulaic in practice.
The goal of science is an understanding of the functioning of the universe. Such understanding is
achieved by means of four components: (a) collection of evidence or observation of specific facts
or phenomena (including those derived from experiments). Science deals only with the material
world (i.e., it seeks a naturalistic explanation), and this is reflected in the old descriptor that the
observations are made using our senses (or instrumental extensions of our senses), (b)
formulation of generalizations about such phenomena, (c) production of causal hypotheses
relating the phenomena (i.e., formulation of explanations, expressions of understanding of the
phenomena). Such understandings are reached by logic and rational thinking. Finally, (d) the
causal hypotheses are tested by means of further observations and experimentation. Two types of
evidence are accepted by practicing scientists: (1) confirmation of hypothesis by data strengthens
its validity, and (2) repeated inconsistency of data with a hypothesis eventually leads to the
rejection of the hypothesis.
7. Articulate a central assumption of science: the universe is real and operates according to
universally consistent rules, and we can discover these rules by logical thought subject to
test through experiments and observations.
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Science demands evidence:
Scientific statements are backed up by evidence. As we have seen the evidence are the results of
experiments that either affirm or reject a hypothesis or answer a question. This is, the evidence
are data collected by researchers.
“Sooner or later, the validity of scientific claims is settled by referring to observations of
phenomena. Hence, scientists concentrate on getting accurate data. Such evidence is obtained by
observations and measurements taken in situations that range from natural settings (such as a
forest) to completely contrived ones (such as the laboratory). To make their observations,
scientists use their own senses, instruments that enhance those senses (such as a microscope),
and instruments that tap characteristics quite different from what humans can sense (such as
magnetic fields). Scientists observe passively (earthquakes, bird migrations), make collections
(rocks, shells, butterflies, flowers), and actively probe the world (e.g., as by boring into the
earth’s crust, coring the trunk of a tree, or administering experimental medicines).”(1)
“In some circumstances, scientists can control conditions deliberately and precisely to obtain
their evidence. They may, for example, control the temperature, change the concentration of
chemicals, or choose which organisms mate with which others. By varying just one condition at
a time, they can hope to identify its exclusive effects on what happens, uncomplicated by
changes in other conditions. Often, however, control of conditions may be impractical (as in
studying stars), or unethical (as in studying people), or likely to distort the natural phenomena (as
in studying wild animals in captivity). In such cases, observations have to be made over a
sufficiently wide range of naturally occurring conditions to infer what the influence of various
factors might be. Because of this reliance on evidence, great value is placed on the development
of better instruments and techniques of observation, and the findings of any one investigator or
group are usually checked by others.”(1)
Thus, science is based on experimental data. These are obtained from natural experiments in
which the researcher is largely a(n) (passive) observer or from controlled experiments performed
mostly in laboratory settings in which conditions are highly controlled. Note that the initial
observations of a research project could be observations made in nature as well as the results of a
previous experiment (often published in the literature).
Science is a blend of logic and imagination:
“Although all sorts of imagination and thought may be used in coming up with hypotheses and
theories, sooner or later scientific arguments must conform to the principles of logical reasoning
– that is, to testing the validity of arguments by applying certain criteria of inference,
demonstration, and common sense. Scientists may often disagree about the value of a particular
piece of evidence, or about the appropriateness of particular assumptions that are made – and
therefore disagree about what conclusions are justified. But they tend to agree about the
principles of logical reasoning that connect evidence and assumptions with conclusions.”(1)
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“Scientists do not work only with data and well-developed theories. Often, they have only
tentative hypotheses about the way things may be. Such hypotheses are widely used in science
for choosing what data to pay attention to and what additional data to seek, and for guiding the
interpretation of data. In fact, the process of formulating and testing hypothesis is one of the core
activities of scientists. To be useful, a hypothesis that cannot in principle be put to the test of
evidence may be interesting, but it is not likely to be scientifically useful.”(1)
8. Explain why a hypothesis must be falsifiable through experiments or observations to be
considered scientific.
Note that a hypothesis may not be falsifiable at one point in time, but when suitable techniques
are developed the hypothesis can be falsified later. Other, well-supported hypotheses are unlikely
to ever become falsifiable.
Note, if the proposed mechanism of a phenomenon is very novel, unexpected, or unlikely the
evidence to corroborate it shall be more extensive, stronger, and broader than that needed to
confirm a more conventional explanation of the facts.
“The use of logic and the close examination of evidence are necessary but not usually sufficient
for the advancement of science. Scientific concepts do not emerge automatically from data or
from any amount of analysis alone. Inventing hypotheses or theories to imagine how the world
works and then figuring out how they can be put to the test of reality is as creative as writing
poetry, composing music, or designing skyscrapers. Sometimes, discoveries in science are made
unexpectedly, even by accident. But knowledge and creative insight are usually required to
recognize the meaning of the unexpected. Aspects of data that have been ignored by one scientist
may lead to new discoveries by another.”(1)
9. Be able to explain how science works as a blend of logic, imagination, and serendipity to
produce theories
Science explains and predicts:
“Scientists strive to make sense of observations of phenomena by constructing explanations for
them that use, or are consistent with, currently accepted scientific principles. Such explanations –
theories – may be either sweeping or restricted, but they must be logically sound and incorporate
a significant body of scientifically valid observations. The credibility of scientific theories often
comes from their ability to show relationships among phenomena that previously seemed
unrelated. The theory of moving continents, for example, has grown in credibility as it has shown
relationships among such diverse phenomena as earthquakes, volcanoes, the match between
types of fossils on different continents, the shapes of continents, and the contours of the ocean
floors.”(1)
The essence of science is validation by observation. But it is not enough for scientific theories to
fit only the observations that are already known. Theories should also fit additional observations
that were not used in formulating the theories in the first place, i.e., theories should have
predictive power. Demonstrating the predictive power of a theory does not necessarily require
the prediction of events in the future. The prediction may be about evidence from the past that
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has not yet been found or studied. A theory about the origins of human beings, for example, can
be tested by new discoveries of human-like fossil remains. This approach is clearly necessary for
the study of processes that usually occur very slowly, such as the building of mountains or aging
of stars. Stars, for example, evolve more slowly than we can usually observe. Theories of
evolution of stars, however, may predict unsuspected relationships between features of starlight
that can then be sought in existing collections of data about stars.”(1)
10. Be able to explain how science produces theories that have both explanatory and
predictive power subject to validation by experiments and observations.
Scientists try to identify and avoid bias:
“When faced with a claim that something is true, scientists respond by asking what evidence
supports it. But scientific evidence can be biased in how the data are interpreted, in the recording
or reporting of the data, or even in the choice of what data to consider in the first place.
Scientists’ nationality, sex, ethnic origin, age, political convictions, and so on may incline them
to look for or emphasize one or another kind of evidence or interpretation. For example, for
many years the study of primates – by male scientists – focused on the competitive social
behavior of males. Not until female scientists entered the field was the importance of female
primates’ community-building behavior recognized.”(1)
“Bias attributable to the investigator, the sample, the method, or the instrument may not be
completely avoidable in every instance, but scientists want to know the possible sources of bias
and how bias is likely to influence evidence. Scientists want, and are expected, to be as alert to
possible bias in their own work as in that of other scientists, although such objectivity is not
always achieved. One safeguard against undetected bias in an area of study is to have many
different investigators or groups of investigators working on it.”(1)
11. Demonstrate with examples that the scientific enterprise is embedded in and influenced
by political, economic, and cultural contexts of the times.
For example, Lysenko (1898-1976) was a Soviet biologist who had a disastrous effect upon
Soviet biology for more than 20 years. He performed experiments by cold treating seeds to
increase grain yields. He claimed that these benefits were inherited by future generations of the
grain. This idea was an example of the long-discredited theory of Jean Baptiste Lamarck, called
"inheritance of acquired characteristics." This is the idea that externally caused changes to an
organism (like losing a finger) can affect future generations (by maybe causing a weak finger).
By this theory, an antelope, stretching its neck to reach higher branches, had evolved into a
giraffe. This sounds like a joke in light of Mendellian genetics and our current understanding of
the DNA molecule. Many people found out that this was a cruel joke indeed. Lysenko's theory fit
well with Stalin's ideas, and he was promoted to the post of director of the Institute of Genetics
of the USSR Academy of Sciences. The previous director, the respected biologist N. I. Vavilov,
was fired, and eventually arrested and exiled to Siberia. Other biologists kept quiet about
genetics, or suffered similar fates. And Soviet biology (and farming techniques) re-entered the
dark ages. Stalin's exiling and killing of the successful farmers (kulaks) did not help matters, and
the USSR suffered droughts in years of abundant rainfall. It was not until after Khruschchev's
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fall from power in 1964 that Lysenko was finally ousted from power, and Soviet biology was
allowed to re-enter the 20th century.
Administrators, policy-makers, and researchers have concluded that it would be very difficult to
keep every hint of bias out of investigations of the effects of drugs on patients if the
investigator’s research is funded by the pharmaceutical company producing the drug under
investigation or the investigator has stock (and, thus, financial interest) in the company. Most
academic and governmental agencies do not allow researchers to have financial interests in the
company whose drugs they study. Similarly, many journals request that investigators state their
financial interests in the drugs they study.
12. Identify potential sources of bias in science attributable to the investigator (e.g., cultural
or ideological), the sample used, the method employed, or the instrumentation used with
the goal of achieving objective results.
Science is not authoritarian:
“It is appropriate in science, as elsewhere, to turn to knowledgeable sources of information and
opinion, usually people who specialize in relevant disciplines. But esteemed authorities have
been wrong many times in the history of science. In the long run, no scientists, however famous
or highly placed, is empowered to decide for other scientists what is true, for none are believed
by other scientists to have special access to the truth. There are no pre-established conclusions
that scientists must reach on the basis of their investigations.”(1)
“In the short run, new ideas that do not mesh well with mainstream ideas may encounter
vigorous criticism, and scientists investigating such ideas may have difficulty obtaining support
for their research. Indeed, challenges to new ideas are the legitimate business of science in
building valid knowledge. Even the most prestigious scientists have occasionally refused to
accept new theories despite there being enough accumulated evidence to convince others. In the
long run, however, theories are judged by their results: when someone comes up with a new or
improved version that explains more phenomena or answers more important questions than the
previous version, the new one eventually takes its place.
13. All science relies upon the acquisition of evidence obtained through experimentation and
observation to test hypotheses and theories rather than upon the acceptance of ideas
based on authority.
THE SCIENTIFIC ENTERPRISE.
“Science, as an enterprise, has individual, social, and institutional dimensions. Scientific activity
is one of the main features of the contemporary world and, perhaps more than any other,
distinguishes our times from earlier centuries.”(1) Science and technology characterize our lives.
Most aspects of daily life are made simpler by technological applications (can you imagine a
house without electricity, a TV, microwave oven, or a personal computer?). Evening newscasts
report daily on scientific breakthroughs in the life sciences, physics, and astronomy. We realize
that technology has/is changed(ing) the environment in which we live and pollution, greenhouse
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gases and global warming have become hotly debated household words and political rallying
points. Similarly, every citizen needs to have an understanding of the cellular and molecular
workings of the body to keep up with the progress in medicine reported daily. How can one be
an active participant in debates on cloning, stem cell research, or genetically modified foods if
one does not have the requisite scientific background?
14. Demonstrate with examples that science is a distinguishing feature of the contemporary
world, and that the scientific enterprise is embedded in and influenced by political,
economic, and cultural contexts of the times.
Science is a complex social activity:
“Scientific work involves many individuals doing many different kinds of work and goes on to
some degree in all nations of the world. Men and woman of all ethnic and national backgrounds
participate in science and its applications. These people – scientists and engineers,
mathematicians, physicians, technicians, computer programmers, librarians, and others – may
focus on scientific knowledge either for its own sake or for a particular practical purpose, and
may be concerned with data gathering, theory building, instrument development, or
communicating.”(1)
Scientists do not live in isolation from the rest of society. There life and thinking are influenced
by their times, just as they are of any other individual of society. But this also means that a
scientist’s scientific work and thinking is influenced by the time and society in which he/she
works.
For example:
(a) Before Mendel, biologists accepted that pangenesis explained how traits were
inherited.
(b) Mendelian genetics and evolution by natural selection provided a scientific
impetus for the eugenics movement of the first half of the 20th century.
(c) For the first 70 year of the 20th century, medicine was very much malecentered. Because women were largely kept out of the sciences and males
were doing all the research. Drug testing was done largely on male volunteers.
“As a social activity, science inevitably reflects social values and viewpoints. The history of
economic theory, for example, has paralleled the development of ideas of social justice – at one
time, economists considered the optimum wage for workers to be no more than what would just
barely allow workers to survive. Before the twentieth century, and well into it, women and
people of color were essentially excluded from most of science by restrictions on their education
and employment opportunities; the remarkable few who overcame those obstacles were even
then likely to have their work belittled by the science establishment.”(1) (See also: Lysenko.)
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Also the topics that are ‘in’ and the questions that should be studied by scientists are affected by
the prevailing needs and fads of society. Up until the 1960s infectious diseases and their
treatment with anti-microbials were major topics in medicine and biomedical research. President
Nixon launched the ‘war-on’ cancer program at the end of the 1960’s and cancer has dominated
medical research for the second half of the 20th century.
“The direction of scientific research is affected by informal influences within the culture of
science itself, such as prevailing opinion on what questions are most interesting or what methods
of investigation are most likely to be fruitful. Elaborate processes involving scientists themselves
have been developed to decide which research proposals receive funding, and committees of
scientists regularly review progress in various disciplines to recommend general priorities and
funding.”(1) Research proposals are evaluated by committees of peers that judge the merits of a
proposal against the prevailing understanding of the topic and the qualifications of both the
institution where the research will be done as well as against the qualifications of the
individual(s) who will do the research. This mechanism protects against wasting funds on
reinventing the wheel or on half-baked ideas. However, such committees may (inadvertently?)
set the direction of the science and make it more difficult to research unorthodox, innovative
explanations.
“Science goes on in many different settings. Scientists are employed by universities, hospitals,
businesses and industry, by government, independent research organizations, and scientific
associations. They may work alone, in small groups, or as members of large research teams.
Their places of work include classrooms, offices, laboratories, and the natural field settings from
space to the bottom of the sea.”(1)
In the early days scientists would mostly work alone and would fund their own work. As
research became more complex and scientists received funding from external agencies,
ownership of research results and intellectual property rights have become equally complex
issues. Thus, scientist that are paid by the government are governmental employees, and are
representatives of the government (e.g., scientists can not travel to Cuba because the US
government does not allow such travel). The university, institution, employer or government
may be the owner of the research results when the work was funded by the university, the
company you work for, or the government.
“Because of the social nature of science, the dissemination of scientific information is crucial to
its progress. Some scientists present their findings and theories in papers that are delivered at
meetings or published in scientific journals (See: lab 3 Scientific papers). Those papers enable
scientists to inform others about their work, to expose their ideas to criticism by other scientists,
and, of course, to stay abreast of scientific developments around the world. The advancement of
information science (knowledge of the nature of information and its manipulation) and the
development of information technologies (especially computer systems) affect all of science.
Those technologies speed up data collection, compilation, and analysis; make new kinds of
analysis practical; and shorten the time between discovery and application.”(1)
An important step in the publishing process of science papers is the peer-review process. Before
a paper is accepted for publication by a scientific journal, the paper is reviewed by two or more
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external reviewers. The latter are researchers with up-to-date, and active knowledge of the
research submitted, that is, they are peers. The peer-review process is a main guarantee for the
scientific quality of the published paper. Is the thesis (explanation) suggested by the submitted
paper plausible in light of our knowledge? Do the experiments provide good arguments that
support the thesis? What arguments are necessary to back up the thesis? Are the experiments
done appropriately? Are the experiments properly analyzed and do the authors draw the right
conclusions?
Because the peer-review process provides a safe-guard to published papers, scientists consider
published claims facts or observations (be it tentative facts until others and further experiments
confirm them) that increase or modify our understanding of a phenomenon. It is important to
distinguish between scientific claims that have been peer-reviewed and those that have not. Quite
often, news media will report on scientific discoveries prior to the peer-review process. Such
claims have not been peer-reviewed and, therefore, lack credibility.
15. Understand that it is the responsibility of scientists to communicate their findings to the
scientific community and, ideally, to the public, and that many scientists participate in
public affairs as both scientists and citizens.
Science is organized into content disciplines and is conducted in various institutions:
“Organizationally, science can be thought of as a collection of all of the different scientific
fields, or content disciplines. From anthropology to zoology, there are dozens of such disciplines.
They differ from one another in many ways, including history, phenomena studied, techniques
and language used, and kinds of outcomes desired. With respect to purpose and philosophy,
however, all are equally scientific and together make up the same scientific endeavor. The
advantage of having disciplines is that they provide a conceptual structure for organizing
research and research findings. The disadvantage is that their divisions do not necessarily match
the way the world works, and they can make communication difficult. In any case, scientific
disciplines do not have fixed borders. Physics shades into chemistry, astronomy, and geology, as
does chemistry into biology and psychology, and so on. New scientific disciplines (astrophysics
and sociobiology, for instance) are continually being formed at the boundaries of others. Some
disciplines grow and break into sub disciplines, which then become disciplines in their own
right.”(1)
“Fundamentally, the various scientific disciplines are alike in their reliance on evidence, the use
of hypothesis and theories, the kinds of logic used, and much more. Nevertheless, they differ
greatly from one another in what phenomena they investigate and in how they go about their
work; in the reliance they place on historical data or on experimental findings and on qualitative
or quantitative methods; in their recourse to fundamental principles; and in how much they draw
on the findings of other sciences. Still, the exchange of techniques, information, and concepts
goes on all the time among scientists, and there are common understandings among them about
what constitutes an investigation that is scientifically valid.”(1)
16. Describe the organization of science into distinctive disciplines with different subject
matter and research agendas, and be able to compare and contrast the questions and
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methods of at least two different scientific disciplines through active study in those
disciplines.
“Universities, industry, and government are also part of the structure of the scientific endeavor.
University research usually emphasizes knowledge for its own sake, although much of it is also
directed toward practical problems. Universities, of course, are also particularly committed to
educating successive generations of scientists, mathematicians, and engineers. Industries and
business usually emphasize research directed to practical ends, but many also sponsor research
that has no immediate obvious applications, partly on the premise that it will be applied fruitfully
in the long run. The federal government funds much of the research in universities and in
industry but also supports and conducts research in its many national laboratories and research
centers. Private foundations, public-interest groups, and state governments also support
research.”(1)
“Funding agencies influence the direction of science by virtue of the decisions they make on
which research to support. Other deliberate controls on science result from federal (and
sometimes local) government regulations on research practices that are deemed to be dangerous
and on the treatment of the human and animal subjects used in experiments.”(1)
There are generally accepted ethical principles in the conduct of science:
“Most scientists conduct themselves according to the ethical norms of science. The strongly held
traditions of accurate record keeping, openness, and replication, buttressed by the critical review
of one’s work by peers, serves to keep the vast majority of scientists well within the bounds of
ethical professional behavior. Sometimes, however, the pressure to get credit for being the first
to publish an idea or observation leads some scientists to withhold information or even to falsify
their findings. Such a violation of the very nature of science impedes science. When discovered,
it is strongly condemned by the scientific community and the agencies that fund research.” (1)
“Another domain of scientific ethics relates to possible harm that could result from scientific
experiments. One aspect is the treatment of live experimental subjects. Modern scientific ethics
require that due regard must be given to the health, comfort, and well-being of animal subjects.
Moreover, research involving human subjects may be conducted only with the informed consent
of the subjects, even if this constraint limits some kinds of potentially important research or
influences the results. Informed consent entails full disclosure of the risks and intended benefits
of the research and the right to refuse to participate. In addition, scientists must not knowingly
subject coworkers, students, the neighborhood, or the community to health or property risks
without their knowledge and consent.” (1)
“The ethics of science also relates to the possible harmful effects of applying the results of
research. The long-term effects of science may be unpredictable, but some idea of what
applications are expected from scientific work can be ascertained by knowing who is interested
in funding it. If, for example, the Department of Defense offers contracts for working on a line of
theoretical mathematics, mathematicians may infer that it has application to new military
technology and therefore would likely be subject to secrecy measures. Military or industrial
secrecy is acceptable to some scientists but not to others. Whether a scientist chooses to work on
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research of great potential risk to humanity, such as nuclear weapons or germ warfare, is
considered by many scientists to be a matter of personal ethics not one of professional ethics.” (1)
Application:
(a) Crops can be modified to be resistant to certain pests or herbicides. What are the
ethical questions scientists should be asked?
(b) To fight human diseases such as malaria or west nile disease (or plagues of crops
or animals), insect vectors can be genetically modified to interrupt transmission of
a disease-causing microorganism. E.g., mosquitoes can be made that no longer
can transmit the malaria parasite or the west nile virus. What ethical questions
should scientists be asked?
(c) Stem cells may be used to stop and reverse the deleterious effects of chronic
diseases. Omnipotent stem cells can be obtained from feta. However, before
therapeutic applications can be established a large amount of stem cell research
must be done. What ethical questions should scientists be asked?
(d) It is possible that organs/tissues can be regenerated in situ by stem cell research or
be grown in vitro and implanted (cloning). Thus an embryo formed by replacing
the nucleus of a zygote with the nucleus of one’s epidermal cell, can be grown
into pancreas tissue in vitro. Because this pancreas tissue has the same genome as
have all cells of your body, it can be transplanted without fear of tissue rejection.
Again, what questions should scientists be asked.
Scientists participate in public affairs both as specialists and as citizens:
“Scientists can bring information, insight and analytical skills to bear on matters of public
concern. Often they can help the public and its representatives to understand the likely causes of
events (such as natural and technological disasters) and to estimate the possible effects of
projected policies (such as ecological effects of various farming methods). Often, they can testify
to what is not possible. In playing this advisory role, scientists are expected to be especially
careful in trying to distinguish fact from interpretation, and research findings from speculation
and opinion; that is, they are expected to make full use of the principles of scientific inquiry.” (1)
“Even so, scientists can seldom bring definitive answers to matters of public debate. Some issues
are too complex to fit within the current scope of science, or there may be little reliable
information available, or the values involved may lie outside of science. Moreover, although
there may be at any one time a broad consensus on the bulk of scientific knowledge, the
agreement does not extend to all scientific issues, let alone to all science-related social issues.
And of course, on issues outside of their expertise, the opinions of scientists should enjoy no
special credibility.” (1)
“In their work, scientists go to great lengths to avoid bias – their own as well as that of others.
But in matters of public interest, scientists, like other people, can be expected to be biased where
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their own personal, corporate, institutional, or community interests are at stake. For example,
because of their commitment to science, many scientists may understandably be less than
objective in their beliefs on how science is to be funded in comparison to other social needs.” (1)
17. Understand that scientist have a generally accepted set of ethical principles for the
conduct of science.
REFERENCES:
(1) Project 2061 of American Association for the Advancement of Science, Science
for all Americans (1990). Oxford University Press, New York, NY.
(2) http://users.aristotle.net/%7Easta/science.html
(3) wysiwyg://12//http://www.angelfire.com/mn2/tisthammerw/science.html
(4) Mayr Ernst. This is biology: the science of the living world (1997).
(5) Lederman Leon, The pleasure of learning, (2004). Nature (August 5) volume 430
p617.
Process of Science (These two objectives will be part of the laboratory portion of the class).
18. Read scientific works written for an informed public and know how to find additional
information that may be needed to fully understand the content of those works.
19. Conduct a scientific investigation, including the formulation of questions and hypotheses,
the development of methods of investigation, the collection and analysis of data, and the
presentation of the work in written and oral scientific style.
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