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Easy explanation of how science works, for 6th to 10th graders. Comments and corrections are welcome (English is not my first language). Thank you!
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The scientific method
© Vittoria Patti 2014
1. I observe
a natural phenomenon A natural phenomenon
is not just an object: rather, it is
something happening or
changing in nature
2. I ask myself a question about some aspects of that phenomenon,
often about cause–effect relationships
Why?
3. I propose a hypothesis:
that is, an educated guess, a possible answer to that question.
Maybe,it’s because...
A hypothesis is just an attempt, and it requires both
imagination and
intelligence:
the only condition is that it should be possible to test it by doing
experiments.
3. I propose a hypothesis:
that is, an educated guess, a possible answer to that question.
If my hypothesis
cannot be tested
in some sort of experiments,
I am no longer using the scientific method correctly.
3. I propose a hypothesis:
that is, an educated guess, a possible answer to that question.
4. I design an experiment which can tell if my hypothesis is right or wrong.
My experiment must be
carefully designed so it can give reliable answers about my hypothesis: that is, its results should clearly show if my hypothesis is
right or wrong!
4. I design an experiment which can tell if my hypothesis is right or wrong.
This is the most difficult step in scientific research. A good scientist, a really creative and innovative one, finds simple and brilliant ways to test his hypothesis through experiments.
4. I design an experiment which can tell if the hypothesis is right or wrong.
Alexander Fleming
4. I design an experiment which can tell if my hypothesis is right or wrong.
Do you know
my story?
5. I run my experiment and collect quantitative data out of it.
The results of my experiment must expressed by measures.
Science is all about
numbers!
5. I run my experiment and collect quantitative data out of it.
6. I examine the results of my experiment
and compare them with those expected
if my hypothesis was right.
6. I examine the results of my experiment
and compare them with those expected
if my hypothesis was right.
There are only two possibilities:
either my data tell that my hypothesis is right
or they show that it is wrong…
And both are fine!
6. I examine the results of my experiment
and compare them with those expected
if my hypothesis was right.
In science, hypotheses proven wrong
are not a failure.
On the contrary, they are very useful. They are the only certain knowledge that the scientific method allows:
in science, you can be absolutely sure only about something
that is proven false.
If it disagrees with experiment, it’s wrong.
In that simple statement
is the key to science.
It doesn’t make any difference how beautiful your guess is,
it doesn’t matter how smart you are
who made the guess, or what [your] name is…
If it disagrees with experiment,
it’s wrong. That’s all there is to it.
Richard Feynman
»
7. If my hypothesis was proven wrong by the experimental data,
it is discarded or (more often) modified.
The same experiments are repeated again and again in the same way, but also changing some experimental conditions, or using different instruments.
8. If my hypothesis was proven right by the experimental data,
new experiments are carried out.
Meanwhile, I report my results to the other scientists working on the same field in the world, and some of them will carry out the same experiments, also to check that I reported them correctly (and that I did not cheat!)
8. If my hypothesis was proven right by the experimental data,
new experiments are carried out.
9. If a particular hypothesis
has always been proven right, under all tested conditions
and with all the instruments available,
it eventually becomes a law or a theory.
The word “law”
is more used in physics, chemistry and astronomy …
9. If a particular hypothesis
has always been proven right, under all tested conditions
and with all the instruments available,
it eventually becomes a law or a theory.
…while the term
“theory”
is mainly used in biology and geology.
9. If a particular hypothesis
has always been proven right, under all tested conditions
and with all the instruments available,
it eventually becomes a law or a theory.
Please notice that in everyday language the words
“hypothesis” and “theory”
are considered having almost the same meaning, while in science they refer to very
different things!
9. If a particular hypothesis
has always been proven right, under all tested conditions
and with all the instruments available,
it eventually becomes a law or a theory.
The scientific method can be used only to study
natural phenomena regarding matter and/or energy.
Each field of study
follows its own method!
…This does not mean
that only matter and energy exist, but it means that the non-material things must be studied using
some different methods.
Each field of study
follows its own method!
Art, music, history, philosophy,
psychology, economics, politics...
they all study non-material things and facts,
and they all have their own method,
different from the scientific method.
Each field of study
follows its own method!
In science, contrary to popular belief,
absolute certainty can never be reached…
Does science produce truth?
…because
only one experiment (if confirmed) is enough to prove a hypothesis
wrong,
even if thousands of previous ones had shown it as being right. Well-established laws and theories
can be overturned, too.
Does science produce truth?
Scientific knowledge is a body of statements
of varying degrees of certainty —
some most unsure,
some nearly sure,
but none
absolutely certain. Richard Feynman
I am among those who think that
science has great beauty.
A scientist in his laboratory
is not only a technician:
he is also a child placed before natural phenomena
which impress him
like a fairy tale.
If I see anything vital around me,
it is precisely
that spirit of adventure, which seems indestructible
and is akin to curiosity.
Marie Curie
Isaac Newton
I do not know what I may appear to the world;
but to myself I seem to have been only like
a boy playing on the seashore, and
diverting myself in now and then
finding a smoother pebble or a prettier shell than ordinary,
whilst the
great ocean of truth lay all undiscovered
before me.