One of the goals of science is to explain various phenomena of the natural world in an objective and unbiased manner. Different people perceive the world differently, due to different educational and cultural backgrounds. For some people a glass of water is half full, for others it is half empty, and still for others it is just a glass of water. Different people perceive and interpret reality differently. If we want to reach an objective description of our world, then we need to reduce these subjective influences. We need standardized procedures in gaining further knowledge of our world. The scientific method is such a standardized procedure in gaining further knowledge in the natural sciences.

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In this edition of TOKTalk we will have a look at the scientific method. What are the steps involved? Listen to find out!

One of the goals of science is to explain the phenomena of the natural world in an objective and unbiased manner. Different people perceive the world differently because they have different educational and cultural backgrounds. For some people a glass of water is half full, for others it is half empty, and still for others it is just a glass of water. Different people perceive and interpret reality differently. If we want to reach an objective description of our world, then we need to reduce these subjective influences. We need standardized procedures for gaining further knowledge of our world.

The scientific method tries to eliminate these subjective influences. It also sets a standard on how further knowledge should be gained in the natural sciences in the first place. Other disciplines, such as history or mathematics use of course different methods for gaining further knowledge.

Most of us are using the scientific method in our every day life, without being consciously aware of it. In the following few minutes I would like to give you an overview of the different steps of the scientific method and I would like to base it on an every day example. Imagine that you want to start your car in the morning to drive to work, and the car refuses to start.

• Step 1: Observation: You turn the key and realize that the car does not start. Maybe you hear a short sound of the turning starter motor, but the sound dies off immediately and the car is quiet again. You also realize that the car radio stops to work and that the head lights dims when you turn the key.
• Step 2: Hypothesis: You are under time pressure and need to leave. We need to isolate the problem and find a solution. Are we out of fuel? Is the temperature to cold for the engine to start? Did a fuse break? Is the battery dead? Is there a mechanical problem with the engine? There are probably many possibilities why a car does not start, and this is not the time for wild guessing. We need to eliminate the options. The car was refueled yesterday, so the missing gasoline is not the problem. Is it a broken fuse? In this case the whole electrical system would not work and there would be no sound at all. Can we exclude a mechanical problem? Possible, but the engine did work before and there was no indication. Maybe, for whatever reason, the battery of the car is empty. Maybe we should start looking here first. A hypothesis is an educated guess and not a wild guess. There should be a good reason for choosing a particular hypothesis.
• Step 3: Experiment: You now test the hypothes by conducting an experiment. You think that the battery is dead, so you exchange the battery or you use the battery of another car to get the engine working. This experiment will either prove your hypothesis correct or wrong.
• Step 4: Conclusion: If your hypothesis was proven correct, if the car works, then you can conclude that the next time when your car starts to act up in a similar way you know where to start looking for the problem. If you repeatedly prove the hypothesis correct and when there is consistency in your results, then the hypothesis becomes a theory. The theory: „Every time when your car does not start, then the battery is broken.“
• Step 5 – Repeat: I can imagine quite well that you are not satisfied with this theory. How can we generalize so much and say that it’s always the battery? But this is what scientific theories are, they are generalized laws. Maybe the next time your car has another problem. And in this case you must adjust your theory. And the old theory is falsified, or proven false. What I mean to say here is, that the scientific method is an iterative, a cyclical process. We do not go through the steps of the scientific method once and then that’s it and we have a final „truth“. We keep on testing and re-testing the theory. Sooner or later the theory will not work anymore and it is time to look for a better theory. Here is an example of a more refined theory: „Every time when the temperature is cold, then the battery breaks down.“ But even this theory will be proven wrong sometime in the future. Maybe the next time you are out of gasoline, you never know what’s possible.

Now is the scientific method itself a scientific theory? Is it possible to experimentally check if the scientific method actually „works“? Of course not. The scientific method is an agreement, an international consensus on how further knowledge is gained in the natural sciences. It is a structured problem solving approach, but it is not a scientific theory in itself. It is not experimentally verifiable or falsifiable. In other words, you can not use the scientific method to test the scientific method. You are not allowed to go in circles like that. The scientific method is above or beyond the the hypothesis, the observations and experiments that it deals with. The scientific method is above or beyond the science itself.

When the number of factors coming into play in a phenomenological complex is too large scientific method in most cases fails. One need only think of the weather, in which case the prediction even for a few days ahead is impossible. Albert Einstein.