• What is the scientific method?
• Why the scientific method?
• Characteristics of the scientific method
• Steps of the scientific method
• Examples of the scientific method

We explain what the scientific method is, its steps and characteristics. Also, step-by-step application examples.

The scientific method can be used in sciences as dissimilar as chemistry or psychology.

What is the scientific method?

Themethod scientist is aprocess Its purpose is to establish relationships between facts to enunciate laws and theories that explain and support the functioning of the world.

It is a rigorous system that has a series of steps and whose purpose is to generate scientific knowledge through the empirical verification of phenomena and facts. In the scientific method the observation to propose a hypothesis which is then tried to check through the experimentation.

Many of the discoveries that we know today were based on a hypothesis that was proven through this method. It is used in most of the Sciences as the chemistry, the physical, the psychology; and it can be applied to explain phenomena of everyday life.

Galileo Galilei was one of the pioneers in the use of the experimental scientific method. Over the years, its application has had multiple interpretations from countless thinkers, including John Locke, Isaac Newton, David Hume, Immanuel Kant, and Karl Hegel. In Discourse of the method , René Descartes established certain rules to guide reason until he was enlightened with the truth in science.

See also:Methodology

Why the scientific method?

Since thehuman being uses reason to develop, has needed the explanation of certain phenomena that govern the world. Depending on the field of action and the implications of the study, there are a number of methods that aid discovery. The historical method is not the same as the logical method, just as the inductive or the deductive.

However, the scientific method predominates and can be extrapolated to almost all sciences since it is based on two fundamental pillars: falsifiability and reproducibility:

• Falsifiability Quality possessed by propositions, laws or theories (which the scientific method considers to be true) of being reevaluated as false. This idea was proposed by the Austrian philosopher, Karl Popper and allows differentiating the scientific knowledge of which it is not.
• Reproducibility Capacity of a certain scientific knowledge to be replicated by another person and at another time under the same conditions obtaining the same result.

Characteristics of the scientific method

The scientific method is verifiable and explanatory.

• Rigorous. The researcher must follow the order of all the steps of the method, without altering any of them.
• Target. It is based on concrete and verifiable facts, and not on wishes, beliefs or opinions. It is the responsibility of the scientist or researcher to keep his subjective vision outside the research.
• Progressive. The knowledge that are obtained are cumulative. They can reinforce or supplement existing research and findings, or even correct them.
• Rational. It uses the reason to make deductions and is based on the logic and not on opinions or beliefs.
• Verifiable. The proposed hypothesis must be able to be applied and empirically verified through experimentation.

Steps of the scientific method

• Observation. Through sensitive activity, man realizes phenomena that are presented to him. In this first step, the phenomena of thereality. It is important to keep objective facts in mind and set aside subjective or personal opinions.
• Induction and questions. The phenomena that have been observed may have a regularity or a particularity that brings them together. This observation raises questions and questions about some fact or phenomenon.
• Hypothesis. Once the question is asked, the hypothesis is the possible explanation for the question asked. This hypothesis must be able to be empirically tested.
• Experimentation. The hypothesis is tested a sufficient number of times to establish regularity.
• Demonstration. With the two previous steps, it will be possible to determine if the hypothesis raised was true, false or irregular. In the event that the hypothesis cannot be verified, a new one may be formulated.
• Thesis. If the hypothesis is not refuted, since it is proven in all cases, they are elaboratedconclusions to dictate laws and scientific theories.

Examples of the scientific method

Polio Vaccine - Jonas Salk

• Observation. In 1947, polio was a very common disease in the United States and the world caused by the poliovirus.
• Induction and questions. Previous studies had succeeded in cultivating the virus in laboratory. Jonas Salk, with the support of the US National Foundation for Infantile Paralysis, decided to develop a vaccine prototype.
• Hypothesis. The development of the first polio vaccine can be obtained through a killed virus.
• Experimentation. For eight years, Salk experimented in the laboratory. The first vaccine was tested by Salk, his family members, and a group of volunteers. After this first test, Salk began a clinical trial in two million children.
• Demonstration. In 1955, following the results of the trial with children, the vaccine was found to be safe and effective in preventing polio in 90% of cases.
• Thesis. Salk developed an injectable vaccine based on the three varieties of the virus grown in monkey tissue and inactivated in formaldehyde. Mass vaccination began right away, and polio cases began to decline considerably.

Polio Vaccine - Albert Sabin

• Observation. At the same time that Salk was researching his vaccine, Albert Sabin was trying to develop a polio vaccine.
• Induction and questions. How to develop a vaccine prototype?
• Hypothesis. A vaccine developed from a live virus can guarantee the immunity of the patient for an extended period.
• Experimentation. Albert Sabin carried out the first tests of his vaccine with himself, his relatives, a group of researchers and detainees in a prison. The massive test was carried out by the Ministry of Health of the Soviet Union in 1957.
• Demonstration. In 1962 the American Public Health Service approved the vaccine designed by Sabin and the World Health Organization (WHO) started using it.
• Thesis. A vaccine was developed in the form of a syrup that is administered orally. This vaccine not only managed to protect people against polio but also made them not carriers of the disease and, therefore, not contagious (this is the main difference with the Salk vaccine). It is today the most widely used vaccine in the fight against this disease.