The Scientific Method

The scientific method taught in schools around the world is a good starting point for understanding science. It tells us much about the practice, benefits and limitations of science. Science is more than a method however, and scientific methods today go beyond the 'textbook' version of the scientific method. This textbook version is worth a closer look.

The textbook description of the scientific method might read as below:

• Observe natural phenomena.
• Formulate an hypothesis to explain the phenomena.
• Use the hypothesis to predict effects.
• Perform experiment(s) to ensure that effects predicted using the hypothesis were achieved.

If it is agreed that the experiments properly test the hypothesis and the results agree with the expectations then the hypothesis becomes a theory and is accepted as proven. If the results of all the experiments do not agree with the expected results then the hypothesis is rejected or modified and retested. It should be remembered that the measure of a good test would be that it maximizes the probability of disproving the hypothesis. A simplified flowchart of the scientific method is shown below.

In practice, the scientific method can only prove a hypothesis false, not prove it true. With any experimental regime, you are only testing a subset of the possible events,scenarios or individuals. How can we be sure that what we tested was representative of what we didn't test. This is a problem common to all inductive techniques. Inductive reasoning generalizes from a set of effects or observations to produce laws or rules.

If the scientific method evolved then it wasn't invented. There continuous discussion of inductive techniques starting with the Greek philosophers, but continuing through the Muslim, Christian and Jewish philosophers in the Middle Ages. In Europe, leading philosophers had advocated a sequence of observation, hypothesis generation then hypothesis testing centuries before the "Scientific Revolution".

Galileo Galilei is often credited with inventing the scientific method but he is a poor choice. His approach to method was not novel for his time and there are examples of good scientific methodology before Galileo. Giuseppe Moletti, a professor at the University of Padua, performed and recorded a well-designed and well-controlled experiment on free fall when Galileo was only 12 years old (see Galileo's Contemporaries). Galileo's writings on method focused on the writings of his predecessors at the University of Padua and the Jesuits' Collegio Romano. Even during Galileo's lifetime, you could find better advocates of empiricism (gaining knowledge through experience or experiment) . Pierre Gassendi and Marin Mersenne were stricter empiricists than Galileo. Galileo would often resort to mind experiments instead of real physical experiments. In fact, Gassendi and Mersenne, arranged for the actual physical execution of some of Galileo's thought experiments.