1.1 Scientific Method
At the core of science lies a problem-solving approach called the scientific method. The scientific method is a scheme for answering scientific questions. The scientific method is used in all the sciences, and has six steps:
- Make an observation.
- Ask a question about this observation.
- Form a hypothesis, or testable explanation, to answer this question
- Make a prediction based on the hypothesis.
- Test the prediction and analyze the results.
- Make a conclusion
The scientific method is used in all the sciences. Scientists in different fields ask different questions and perform different tests, but everyone uses the same core approach to find answers that are logical and supported by evidence. Each step in the scientific method can be repeated or redone as new understanding occurs.
This method is not rigid and allows a scientist to move back and forth between the steps as needed. This diagram illustrates the scientific method.
Example of the scientific method
Say you live in a cold climate in Northern Europe. You have observed (step 1) that a pond nearby freezes faster than the ocean. Both the pond and ocean have similar weather, which raises the question (step 2), why does the pond freeze before the ocean? After pondering this question, you hypothesize (step 3) that the ocean has salt in it. The prediction (step 4) is that salt lowers the temperature at which the water will freeze. A good hypothesis must be testable, and the test must be repeatable (step 5). To test this hypothesis and prediction, other factors which could affect the water freezing must be removed. Other factors could be wind, waves, or boat traffic. If we were to take two containers of water, one with salt and one without, these other factors would be removed when testing the hypothesis.
This example provides the means to design an experiment, run the experiment, analyze the results of the experiment, and then make a conclusion (step 6). While running the experiment, data could be gathered on what temperature each container starts to freeze. This information would allow a prediction with more detail than was originally proposed. The double-pointed arrows in the diagram illustrate this ability to easily go between steps and adjust steps when warranted.
When using the scientific method, these three precautions should be noted:
- The scientific method can only disprove hypotheses. A scientific theory can never be proven to be 100% correct, because new information may become available which contradicts previous tests and results.
- Correlation is not causation. A correlation is an analysis of data without any understanding of the conditions causing that data to occur. The best science tries to determine the cause behind what is being observed.
- Selective windowing should be avoided. Selective windows pick and choose which facts or data to examine so that the desired conclusion is achieved. The whole truth and all aspects of the tests should be present in the scientific method.