I.
What Science Is
A.
National Academy of Sciences, 1999
“Science is a particular way of knowing about the world. In science,
explanations are limited to those base on observations and
experiments that can be substantiated by other scientists.
Explanations that cannot be based on empirical evidence are not
part of science.”
B.
Edward Teller 1991
“A scientist has three responsibilities: one is to understand, two is to
explain that understanding, and three is to apply the result of that
understanding.”
C.
How scientist do their jobs
1.
2.
3.
4.
Create new methods and techniques for observing/experimenting
Devise experiments to produce useful observations and data
Develop theories to explain observations and data
Use logic and reasoning to form conclusions
D. How scientists share their results
1. Multimedia presentations at professional meetings
2. Carefully written papers in peer-reviewed journals
a. Originality of the research
b. Quality of the methods and of the data presented
c. Reasonableness of the conclusions presented
3. Published science is always open to modification or falsification
a.
b.
c.
d.
Art/Theatre/Literature are personal expressions with no “right” answer
Religion requires a personal faith and is not falsifiable
Science can always be falsified and a better explanation proposed
Scientific claims should always be viewed as tentative
E. What Science is not
1.
2.
3.
4.
5.
Sometimes giving counter-example is helpful in defining a term
Astronomy vs. Astrology
Psychology vs. Parapsychology
Cosmology vs. Mythology
Sometimes this is not so simple: Superstring Theory
F.
How Science is Applied
1.
2.
Engineers and Technologists apply science to specific problems
Many useful products are applications of science
a.
b.
c.
3.
Computers
Pharmaceutical Drugs
Communication devices: cell phones, satellites, etc…
Some applications of science have dubious benefits
a.
b.
c.
Weapons of Mass Destruction
Illegal Drugs
Greenhouse gases and Ozone depleting gases
G. Science and Culture
1.
2.
3.
4.
Western Culture and Modern Science are Compatible
Other cultures value science/technology in different ways
Chinese medicine has shown value in healing unaccounted for by
modern science
Western lifestyle made possible by science may not be perceived
as superior by all other cultures
II.
Science for All Americans (AAAS, 1990)
A.
The Scientific World View
1.
2.
3.
4.
B.
Scientific Inquiry
1.
2.
3.
4.
5.
C.
The world is understandable
Scientific ideas are subject to change
Scientific knowledge is durable
Science cannot provide complete answers to all questions
Science demands evidence
Science is a blend of logic and imagination
Science explains and predicts
Scientists try to identify and avoid bias
Science is not authoritarian
The Scientific Enterprise
1.
2.
3.
4.
Science is a complex social activity
Science is organized into content disciplines and is conducted in
various institutions
There are generally accepted ethical principles in the conduct of
science
Scientists participate in public affairs both as specialists and
citizens
III. Themes of Science
A.
Science as a Way of Thinking
1.
Beliefs
a.
b.
2.
Curiosity
a.
b.
c.
d.
3.
Science is ideally based only on evidence and is tentative
Scientists are human, however, and begin to “believe” their theories
Scientist tend to explore and ask questions about almost anything
Examples: Leonardo da Vinci, Benjamin Franklin
They are motivated to “find the truth”
This curiosity can lead them to risk ridicule or controversy to find out
Imagination
a.
b.
c.
d.
Great leaps in science often come because of a imaginative scientist
Kekule’s dream about the structure of benzene
Thomson’s “Plum Pudding” analogy for the structure of atoms
Einstein: “imagination is more important than knowledge”
4. Reasoning
a. Inductive Reasoning: piecing together facts and principles to arrive at
new conclusions
b. Deductive Reasoning: applying known principles to new situations
c. Hypothetical-Deductive approach: state hypothesis, experiment to
prove or disprove it
5. Cause and Effect Relationships
a. Science experiments try to produce an effect with a controlled cause
b. Science tries to explain why, rather than just find out if
c. Cause and Effect is often difficult to establish
i. If you cut off its oxygen supply, a mouse will die
ii. If you smoke, you will get lung cancer
6. Skepticism
•
•
•
Science continually examines itself as well as the natural world
Scientific principles are always modifiable and falsifiable
Quantum Mechanics, for example, has modified Classical Physics
7. Objectivity and Open-Mindedness
a. This attitude allows scientists to recognize novel observations
b. Scientists are human; they have biases and beliefs too
B. Science as a Way of Investigating
1. “The” scientific process—Karl Pearson, 1937
a.
b.
c.
d.
e.
Observing, Collecting Data, Hypothesizing, Experimenting, Concluding
Science instruction often teaches this process as absolute
Scientists rarely follow this, or any other, rigid process
Each scientist has a unique way of learning about nature
Percy Bridgman (1950) “The scientific method, as far as it is a
method, is nothing more than doing one’s damndest with one’s
mind, no holds barred.”
2. Hypothesis
a. A statement of relationships that can be tested: “Increased light
intensity will cause increased growth rates of pea plants”
b. Difficult to prove a positive statement, but easier to disprove a negative
statement: “Increased light will have no effect on the growth rate of pea
plants”—Null Hypothesis
c. Alternative Hypothesis is the logical conclusion when Null is disproved
d. Hypotheses can be revised: “Increased red light intensity…”
3. Observation
•
•
•
•
•
Data and information gathered and organized to make sense of nature
Repeated observations lead to “facts” and theories
Tycho Brahe’s astronomical observations used by Kepler to theorize
about the elliptical orbits of planets
The mind can miss observations or manufacture false ones
We “see with our minds” not just our eyes
4. Experimentation
a.
b.
c.
d.
Test ideas and determine cause/effect using controls
Greek “science” relied only on reasoning through their ideas
Modern science tests ideas with physical experiments
Independent Variable (Cause): what is changed by the researcher (light
intensity)
e. Dependent Variable (Effect): what is observed by the researcher
(growth rate)
f. Control: holding all other variables constant so that only one variable is
causing the change (temperature, humidity, etc…)
5. Mathematics
a.
b.
c.
d.
Bacon: “Mathematics is the door and the key to science”
Math helps us express models to explain our observations
Mathematical descriptions of the unobservable atom
Galileo’s observation: s = 16t2 for distance a falling object falls
D. Science as a Body of Knowledge
1. Facts
a.
b.
c.
d.
e.
f.
Directly observable at any time
Can be “one-time” events (volcanic eruption)
Always contain error: Mass of a proton = 1.008 ± 0.001 amu
Science wants to know why the fact is so, not just the fact itself
Fact: food poisoning results from eating old or damaged canned foods
Context: botulinum bacteria produce toxins that lead to food poisoning
2. Concepts
a. Properties in common to a certain set of events of objects
b. Elements of a concept: name, definition, attributes, values, examples
c. Examples:
i. Biology: tree, ape, enzyme
ii. Chemistry: reaction, element, isotope
iii. Physics: wave, solid, x-ray
3. Principles and Laws
a. General descriptions of behavior under a limited set of conditions (How
things happen)
b. Broader than a concept
c. Often accepted as facts; Often described by a mathematical equation
d. Example:
Chemistry: gas laws describe gas behavior under certain conditions
PV = nRT
4. Theories
a. Explanations of reality that go beyond the directly observable
b. Attempt to explain Why things happen, not just How
c. Examples
a. Atomic Theory
b. Theory of Evolution
d. Never become “Fact”; can always be revised or disproved by new data
a. Make predictions base on the theory
b. If prediction occurs, theory survives to be tested again
5. Models
a. Representation of something we can’t observe directly
b. Provide physical or mental images for us to examine
a. Bohr model of the atom
b. Wave model of light
c. Teachers need to remind students that models are not reality
a. Atoms are not really mini solar systems
b. Light is more than a wave (particle, energy, etc…)
E. Science, Technology, and Society
1. All three greatly influence each other
a. Government Agency NSF (society) provides funds to purchase an
NMR spectrometer (technology) to study structure of proteins (science)
b. Molecular Biologists (science) use Genetic Engineering (technology) to
produce corn immune to disease. The FDA regulates the use of this
corn for human consumption (society)
2. Technology
a. Technology is the application of science to specific problems
b. This often results in useable products for society
c. Technology advances when science allows and society demands it
i. Cheap home computers
ii. Airplane travel across the country
3. Society
a. Society (through government) decides what science to fund:
biomedical research gets more funding than physical sciences
b. Society also decides what technology is desired: cloning, stem cells