PROFESSOR: Hello,
students, we're
going to continue our
discussion of science,
a way of knowing, and in
this video lesson, talk
about the scientific method.
The scientific method is a
iterative, stepwise process.
It's a formal way in
which science is done.
Now not all scientific
experimentation
is done following exactly the
steps of the scientific method,
but it still recognized as
the formal procedures by which
science is done, and may involve
first observing, observing
some natural phenomena
that a scientist,
or a group of scientists, are
interested in understanding.
Second, coming up
with a hypothesis
regarding how those
phenomena behaves.
Third, performing some
experimental or observational
test of this hypothesis.
Then evaluating the
results, revising
or refining the
hypothesis as necessary
if the results, for example,
refute the hypothesis,
you would revise the hypothesis.
And then repeat the above
steps until understanding
is achieved.
So scientific method
starts with observation,
coming up the hypothesis,
testing the hypothesis,
evaluating the results,
revising and repeating.
There are a few terms
that we associate
with the scientific method.
One is the term hypothesis,
which we mentioned.
It's a conjecture.
It's an educated guess
about how something works.
Hypotheses then guild
our experiments,
and the best hypotheses are
ones that can be falsified.
If a hypothesis cannot
possibly be falsified,
then it's not very
good hypothesis.
Another term that is used to
describe the scientific method
is a model.
A model is a sort
of logical framework
intended to represent reality.
Oftentimes it has
a visual element
to depict how
something would work.
A theory is a very
extensive explanation
of a phenomenon
that is supported
by a vast body of evidence and
has withstood repeated test.
Notice that theory is the
very highest of these terms.
It is the grand
explanation that may only
be achieved after decades
of experimental test
of hypotheses.
Another term that is
sometimes used is law.
A law is usually a short,
and I say pithy, statement
or equation that
concisely describes
behavior of natural systems.
An example would be F equals ma.
See laws are oftentimes have
equations associated with them.
Or the Ideal Gas
Law, PV equals nRT,
or statements Newton's law.
I'm not giving you
these equations for you
to write down, I'm
just giving them
as examples of what
we mean by a law.
It's either an equation or very
short, concise statement that
describes behavior of a system.
In this slide, I list several
relatively well known theories.
The point is that there are only
a few, relatively few, theories
and they are very important.
These are the
grand explanations.
Again theory is much more
important than hypothesis.
Hypotheses are everyday.
Theory is once in a
decade or century.
We have things like the
Theory of Relativity,
The Quantum Theory, Big Bang
Theory, Theory of Gravity,
Theory of Electromagnetism,
Atomic Theory, Kinetic Theory,
Molecular Orbital Theory.
Again I'm not expecting you
to write any of these down
or know them, only to
point out that theories
are relatively few and are
extremely important in science.
In this semester, we will talk
about some of these series
at the bottom of this list, Cell
Theory, Theory of Evolution,
Germ Theory, Plate Tectonic
Theory, and Climate Change
Theory.
In the next couple of slides,
I want to talk about some
of the characteristics of
the scientific approach,
of scientific method.
The methods of science usually
involve collaborative efforts.
That is, usually,
scientists working
in teams, sometimes
very large teams
in performing their experiments.
The reproducibility of
experimental results
is extremely
important in science.
That is, if an experiment
can only be done once,
it might be called a fluke.
Experiments have
to be reproduced
in order to be trusted.
Another characteristic
of the scientific method,
or the way we do science, is
that involves open dialogue
between scientist.
Scientists share their data
and results quite freely.
Oftentimes at professional
meetings or some
are by publishing in
scientific journals,
because the scientific
process is itself
a consensus building process.
A given model or an
explanation will only
be accepted by the larger
scientific community
if it can be reproduced
and accepted by others.
That is, if there's a consensus
reached by those scientists who
are studying some phenomena as
to a particular explanation,
or particular model,
particular theory.
Science involves logical
reasoning processes,
both inductive and
deductive reasoning.
The scientific
method also involves
a heavy use of
mathematical tools
and reliance on measurement
and quantitative methods.
In addition, the
scientific method
is a very objective approach.
That is, scientists usually
are quite skeptical.
They're skeptical of
their own results.
They're skeptical of
the results of others.
But scientists must also keep an
open mind, must be open-minded
and unbiased.
That is, not to approach a
particular investigation having
a preconceived notion
as to the outcome.
Scientists also
are characterized
by needing to be ethical.
Ethical both in the way
they conduct experiments,
and the way they report
their results to others.
The scientific method
also involves the use
of controls and
variables, what we
refer to as independent
and dependent variables.
And lastly on this
slide, I have what
is called the KISS
principle, which is sometimes
referred to Occam's razor.
Now KISS stands for
keep it simple sonny.
The keep it simple sonny
principle, that is, in science,
scientist favor coming up with
the simplest explanation that
is consistent with
all the observations
rather than coming up was
some elaborate explanation.
A few other things to mention
about the scientific method,
progress in science is based
on the peer review process.
That is, when scientists attempt
to publish their findings,
or request funding from
the federal government
or other agencies, there
is a peer review process
in which one
scientist will review
the writings, the proposal,
of another scientist.
Often this peer review process
is called a blind review,
where one scientist
doesn't know who
is reviewing his or her
proposals or manuscripts.
And the purpose of this is
to maintain high standards
in science.
Again as we said, science
progresses through a consensus
building process,
And also people
in a non-scientific
world should realize
that scientific models,
laws, and theories are always
being reviewed and
challenged and tested
over time, which
can, in some cases,
lead to revisions of theories.
So if someone
criticizes a theory
by saying it has
been modified, well
that is the very nature of
the way science is done.
OK we're going to pause.
I'll give you a
very briefly quiz.
And then, after you successfully
answer the questions
of this quiz, you'll
be able to print
a brief summary of the notes
for the past few video lectures.
Good luck.
