Regardless of the many different tools and methods used in research, all scientific investigations are based on observation and experimentation, key elements of the scientific method. The scientific method is one of the most powerful tools of modern science.

Often, science textbooks describe "the scientific method," as if there is a single, simple flow chart that all scientists follow. This is an oversimplification. Although such flow charts incorporate much of what scientists do, you should not conclude that scientists necessarily progress through the steps of the process in one prescribed, linear order. That said, we will introduce you to this traditional flow chart, which consists of five main steps: making observations; asking questions; forming hypotheses; making predictions based on the hypotheses; and testing the predictions by making additional observations or conducting experiments. We will highlight this version of the scientific method using an experiment on the decline of frog populations.


The scientific method is one of the most powerful tools of modern science. In the scientific method, two kinds of logic are employed. The formation of a hypothesis requires inductive logic. Using inductive logic, specific observations or facts are used to develop a new hypothesis that is compatible with those observations or facts. In other words, inductive logic moves from specific facts to a more general statement. More than one hypothesis may be compatible with the facts, which is why a hypothesis must now be tested.

The next step in the scientific method is to apply a different form of logic—deductive logic—to make predictions based on a hypothesis. Deductive logic starts with a statement believed to be true (or, a hypothesis that is to be tested) and then goes on to predict what facts would also have to be true to be compatible with that statement.

Once predictions are made from a hypothesis, experiments can be designed to test those predictions. The most informative experiments are those that have the ability to show that the prediction is wrong. If the prediction is wrong, the hypothesis must be questioned, modified, or rejected.

The traditional textbook description of the scientific method includes a linear series of five steps. However, this traditional description doesn't describe how science is often conducted in real life. Scientific investigations take many forms and are performed by individuals or teams with their own personalities, creativity, knowledge, and experiences. For more information on how scientists conduct science in the real world, click the link below.

Understanding how science really works

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Textbook Reference: Concept 1.5 Science Is Based on Quantitative Observations, Experiments, and Reasoning