The document outlines the scientific method, which includes observing a phenomenon, asking questions, proposing and testing hypotheses, running experiments, and interpreting results. It emphasizes that science is about evidence, and a hypothesis can be considered valid or invalid based on experimental data, with discard or modification being a natural part of the process. Lastly, it distinguishes between the scientific method and other methods used in different fields, asserting that absolute certainty can never be achieved in science.

1. 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. If my hypothesis cannot be tested in some sort of experiments, I am no longer using the scientific method correctly.
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!
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.
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!
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! 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.
8. If my hypothesis was proven right by the experimental data, new experiments are carried out.
The same experiments are repeated again and again in the same way, but also changing some experimental conditions, or using different instruments.
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!)
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, while the term “theory” is mainly used in biology and geology.
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!

2. 10. Each field of study follows its own method!
The scientific method can be used only to study natural phenomena regarding matter and/or energy. 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.
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.
11. Does science produce truth?
In science, contrary to popular belief, absolute certainty can never be reached……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.
«Scientific knowledge is a body of statements of varying degrees of certainty — some most unsure, some nearly sure, but none absolutely certain» (Richard Feynman)
12. And yet…
«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)
«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» (Isaac Newton)