The Scientific Method

All sciences, including social sciences, rely on variants of what is called the scientific method, which is a systematic approach to research. For example, a psychologist investigating the effect of noise on people's ability to learn chemistry and a chemist interested in measuring the heat released by the combustion of gaseous hydrogen in the presence of air would use roughly the same procedure in their research. The first step is to define the problem carefully. The next is to conduct experiments, make detailed observations, and record information or data concerning the system, i.e., the part of the universe under investigation. (In the examples mentioned above, the systems are the group of people studied by the psychologist and a mixture of hydrogen and air, respectively).

The data obtained in research can be qualitative, consisting of general observations about the system, and quantitative, involving numbers obtained from various measurements of the system. In general, chemists use standardized symbols and equations in recording their measurements and observations. This form of representation not only simplifies the recording process but also provides a common basis for communication with other chemists.

Once the experiments are completed and the data is recorded, the next step in the scientific method is interpretation, where the scientist tries to explain the observed phenomenon. Based on the collected data, the researcher formulates a hypothesis, which is a tentative explanation of a set of observations. Then, additional experiments are designed to test the validity of the hypothesis in as many ways as possible, and the process starts again. The main steps of the research process are summarized in the figure.

After collecting a large volume of data, it is often advisable to summarize the information concisely, such as into a law. In science, a law is a concise statement, either verbal or mathematical, of a relationship between phenomena that is always the same under the same conditions. For example, Sir Isaac Newton's second law of motion, which states that force is equal to mass times acceleration (F = ma). The meaning of this law is that an increase in mass or acceleration of an object always proportionally increases its force, while a decrease in mass or acceleration undoubtedly reduces its force.

Hypotheses that withstand many experimental tests of their validity can become theories. A theory is a unifying principle that explains a set of facts or the laws based on those facts. Theories are also subject to constant evaluation. If a theory is refuted in an experiment, it must be discarded or modified to make it compatible with experimental observations. Approving or discarding a theory can take years or even centuries, in part due to the lack of necessary technology. The atomic theory, for example, took over 2,000 years to confirm this fundamental principle of chemistry proposed by Democritus, an ancient Greek philosopher. A more contemporary example is the Big Bang theory about the origin of the universe.

Scientific advancements are seldom, if ever, achieved rigidly step by step. Sometimes a law precedes the corresponding theory, or vice versa. Two scientists may start working on a project with exactly the same goal and end up with entirely different approaches. After all, scientists are human beings, and their way of thinking and working is subject to significant influence from their backgrounds, training, and personality.

The development of science has been uneven and sometimes illogical. Great discoveries result from the contributions and experiences accumulated by many researchers, although credit for the formulation of a theory or law is usually given to a single individual. Of course, luck plays a role in scientific discoveries, although it has been said that 'opportunities favor prepared minds.' It takes attention and the ability to recognize the significance of an accidental discovery and make the most of it. It is very common for the general public to hear only about spectacular scientific advances. However, for every one of those well-known stories, there are hundreds of cases of scientists who have spent years working on projects that ultimately proved unsuccessful, and in which positive results are achieved only after many errors and at such a slow pace that they go unnoticed. Even these unsuccessful research endeavors somehow contribute to the ongoing advancement of our understanding of the physical universe. It is the love of research that keeps many scientists in the laboratory.