NATURAL SCIENCES
All science, measured against reality, is
primitive and childlike. And yet it is the
most precious thing we have.
Albert Einstein
Natural Sciences
• Study the material world and only the
material world.
• N. Science attempts to answer the question
WHY? Or HOW?
• Attempt to make generalizations about entire
collections of things. From these
generalizations, new hypotheses are formed.
• Search for regularities or recurrent
relationships to explain and describe.
• What are some examples of scientific beliefs
that have changed?
• Is science, broadly and over time, gtting closer
to truth? In the long run, is it truly selfcorrecting?
• Which technological sense perception
extensions further our scientific knowledge?
• Science operates on the assumption that by
isolating key variables we can discover the
truth.
• Scientism: the belief that science is the only
way we can make sense of reality and discover
truth.
• Agree or disagree: Science is the only true
road to knowledge. It is the dominant
cognitive paradigm.
• Which is more certain, science or math?
Classification
• We use reasoning to make and apply generalizations,
we use language to name the categories. We use
emotion and sensory perception to observe and
gather empirical data.
Questions
• What is the difference between describing and
explaining?
• What is the difference between a science class in which
you learn that and one in which you learn how?
• Are there times when the sciences rely on each other?
When? Examples?
• How many results of science surround you, and how
much do you trust them without even noticing?
• What are some connotations associated with the word
“science” or “scientist”?
• What motivates science?
Pseudo-Science
• Michael Shermer, “Why People Believe
Strange Things”
• Important to remember:
– Might be culturally valid
– Other perspectives must at least be acknowledged
– Recognize their contribution to an understanding
of the whole
How do we recognize pseudo-Science?
– The discoverer bypasses peer review to go directly to the
media.
– The discoverer claims that the scientific establishment,
possibly as part of a larger conspiracy, is trying to suppress
his work.
– The evidence is extremely hard to detect.
– The evidence takes the form of individual observations or
stories, not able to be generalized.
– The discoverer claims that knowledge is ancient and hence
more credible.
– The discoverer has worked alone.
– The discoverer needs to propose modification to the laws
of nature in order that his findings be credible.
• Genuine Science:
– Hypotheses are testable
– Hypotheses are general
in nature and don’t
make exceptions every
time a counter example
is provided.
– Hyp. are precise.
– A distinctive method is
used when testing the
hypothesis.
• Pseudo Science:
– Claims the status of
science while lacking its
substance (magic
crystals).
– Not testable; tests are
not replicable.
– Ad hoc exceptions
– Vague
– Expectations/confirmati
on bias.
Gaining Knowledge through Science
• Even “failure” brings new knowledge to light.
• Science is a living archive—always shifting,
changing, reproving or disproving aspects of
itself.
• Small, particular results cumulatively add to
each other in an international collaborative
effort.
Questions…
• What are the relative roles of previous
knowledge and current conjecture or
hypothesis?
• What makes a hypothesis a good hypothesis?
• How is reading about an experiment different
from doing it yourself?
• What is the responsibility of the scientist in
the knowledge he or she gains?
Kinds of Scientists
• Experimental
• Theoretical (working mostly with
mathematics/numbers learned in previous
experimentation)
• Field scientist: go out and observe natural
phenomena.
Inductivism (classic scientific method)
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Observation/find pattern
Hypothesis
Experiment
Law
Theory
• A GOOD experiment will have:
– Controllability
– Measurability
– Repeatability
Problems with the scientific method
– OBSERVATION:
• Expert seeing—scientific
equipment takes practice
• Expectation
• The observer effect: the act
of observing can effect
what we see.
• There is fallibility through
sense perception, however,
science allows for
correction or errors
through repeated
experimentation.
• TESTING HYPOTHESIS:
– Confirmation bias—Charles
Darwin example—he
would write down
observations that opposed
his expected results
because he was worried he
wouldn’t remember them.
– Background assumptions:
The earth is flat.
– Multitude of hypotheses
with a given set of data
Problems/room for error
• The problem of Induction (opposite of math, which is
deductive)
– Moves from the observed to the unobserved, leaving room
for greater error.
• Practical problems:
– Why place our faith in science if it really can’t be proven?
– How many observations should be made before you can
safely make a generalization?
• Theoretical Problems:
– Should scientists never theorize? Should they only report
out what they observe?
Announcements
• EE: If you have not yet updated your essay
question for approval, you are late!
• HELP! Monday from 3pm-4pm, lower gym—
setting up for IB breakfast (CAS!)
Theories and laws
• From pages 226-227 of Cambridge text
“If your experimental results confirm your
hypothesis, then you may have discovered a
scientific law…Finally, you may develop a theory
which explains and unifies various laws in terms
of some underlying principles. A good theory
explains why the laws are the way they are and
provides a focus for further research.”
Example (also from text)
Claudius Ptolemy (85-165) created a model of the universe in which the earth
was the center.
• Observation: astronomers made more specific observations, which
necessitated adjustment of Ptolemy’s model until it was irrelevant.
• Hypothesis: Copernicus (1472-1543) hypothesized that the sun was at the
center of the universe, the planets revolved around it.
• Prediction: Copernicus predicted that planets therefore would “appear” to
change size when viewed from the earth if it does indeed orbit the sun.
Galileo (1564-1642) confirmed this was true.
• Law: Johannes Keplar (1571-1630) Developed laws of planetary motion.
• Theory: Isaac Newton (1642-1727) developed his theory of gravity. This
was part of a more general theory that enabled Newton to explain why
objects (apples) fall to earth, why people have weight, and the orbit of the
planets. Newtonian physics also allowed astronomers to eventually make
accurate predictions that led to the discovery of new planets such as
Neptune.
Example
• Observation: When I throw a pen at the wall, it makes a
louder noise than when I throw a ball of paper at the wall.
• Hypothesis: Every pen I throw at the wall will create a
louder noise than every ball of paper.
• Experiment: threw 100 pens and 100 balls of paper at the
wall. All of the pens registered a higher decibel of noise
than all of the balls of paper.
• Law: When thrown at a wall, pens make a louder noise
than balls of paper.
• Theory: objects made of hard plastic, when projected
towards a hard surface, will register a higher decibel of
noise than objects made of softer, more pliable materials.
Theories
• Defined: the overarching constructs that
encompass and explain many laws.
• Refer to unobservable entities or properties
that stand behind the measurements we make
(atoms, natural selection, curvature of space)
• Are interrelated in such a way that they
explain not only a particular law or
phenomenon, but whole ranges of each.
• Chaos theory: reveals a new kind of pattern
within the turbulence of nature, with limits on
the degree to which it can be predicted.
• Butterfly effect: tiny, immeasurable events can
cause major ones.
Read: Ray Bradbury’s “The Sound of Thunder”
Karl Popper
• Karl Popper: distrustful of sciences that
attempted to explain everything (psychoanalysis).
He believed that rather than spend time trying to
prove something over and over again, our time
would be better spent trying to disprove it. A
genuine scientific theory puts itself at risk. A
theory that explains everything explains nothing.
• We cannot prove a law is true, but refutation is
decisive: we need only one counter example to
prove that a law is false. More certainty!
Rationalists vs. Empiricists
• Rationalists: reason is the main source of
knowledge
• Empiricists: someone who sees experience as
the main source of knowledge.
• The rationalist is more likely to stick with a
beautiful theory, the empiricist is more likely
to stick to the observational evidence.
Testing for Truth
• Correspondence: statements we make
correspond to what we observe in the world.
EVIDENCE
• Coherence: Examine knowledge claims
themselves for consistency, freedom from
contradiction.
• Pragmatic: Demands that the statements work in
practical terms.
– When we have two equivalent theories, we choose the
theory that is conceptually the simplest with the “most
economical conceptual formulation.” (Ockhams Razor/Law
of Parsimony)
– We assume that theories that are mathematically beautiful
and symmetric are more likely to be true and search very
hard for experimental evidence to confirm them.
– We assume the laws of physics we develop are applicable
all over the physical universe.
– Heisenberg: the scientist affects the data by the very act of
trying to measure it.
Scientific Progress
• “Normal Science”: a period during which most
scientists are working within a paradigm,
although they make take the paradigm itself
for granted.
• “Scientific revolutions”: When scientists
become dissatisfied with a prevailing
paradigm and create a whole new way of
looking at things.
Paradigms in science
• Newtonian mechanics,
• Atomic theory in chemistry
• Evolutionary theory in biology
• Others?
Thomas Kuhn’s Theory of Science
– During periods of normal science, most scientists do
not question the paradigm in which they are
operating and focus instead on solving problems.
– The history of science suggests that, rather than
progressing smoothly, science goes through a series of
revolutionary jumps.
– During periods of scientific crisis, there is no purely
rational way of deciding between rival paradigms
*He likened a scientific paradigm shift to a religious
conversion.
Criticisms of Science as the “only” way
of knowing
• Fallibility of sense perception, even when extended by
technology.
• Limits of inductive reasoning
• Human fallibility in experimental methods
• Bias that comes with theory and observation
• Expectation
• The very act of observation may in some circumstances
affect the thing that we are observing.
• Being close minded or unwilling to accept outliers as
data.
5/17/2013
Homework:
• Blog
• Find ONE example of the natural sciences in the
news (controversial or persuasive, preferable)
• Read ALL presentation materials; try to choose a
topic.
• Continue to research EE, create annotated
bibliography AS YOU GO. Begin a rough outline.
Overlap
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Imagination
Technology
Ethics
Human Sciences
History
Beauty:
– “the patterns found in the world of sense perception
(often using math or technology) and through the arts
in the patterns created from all the raw material of
experience. In all these areas, their practitioners are
apt to have moments of pure admiration.”
• Can science be bad, wrong…while attempting
persuasion?
• http://www.ted.com/talks/ben_goldacre_batt
ling_bad_science.html
5/20/13
• Reminder: Help in lower gym 3:00-4:00. CAS!
• Tomorrow: Please arrive in the lower gym by
7:30. Dress nicely.
• Field Trip forms: Due by Wednesday or you
have to stay here!
• BLOG—presentation examples found there.
• Do science and religion ever work together?
• Can Science be a moral compass?
• http://www.ted.com/talks/sam_harris_scienc
e_can_show_what_s_right.html
Science as a persuasive tool?
• Is science ever used as a tool to market an
item?
• Should all beliefs be subject to scientific tests?
(Example: if I say that my racism is based in
my belief that white people are biologically
different from black people.)
What are the most controversial topics
in science currently?
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Why are they controversial?
What is at stake?
What are the implications of both sides?
How does one ‘decide’ what is right or wrong
in this area?