The procedure that scientists use is also a standard form of argument. Its conclusions only give you the likelihood or the probability that something is true (if your theory or hypothesis is confirmed), and not the certainty that it’s true. But when it is done correctly, the conclusions it reaches are very well-grounded in experimental evidence. Here’s a rough outline of how the procedure works.
- Observation: Something is observed in the world which invokes your curiosity.
- Theory: An idea is proposed which could explain why the thing which you observed happened, or why it is what it is. This is the part of the procedure where scientists can get quite creative and imaginative.
- Prediction: A test is planned which could prove or disprove the theory. As part of the plan, the scientist will offer a proposition in this form: “If my theory is true, then the experiment will have [whatever] result.”
- Experiment: The test is performed, and the results are recorded.
- Successful Result: If the prediction you made came true, then the theory devised is strengthened, not proved or made certain. The theory is “verified.” And then we go back and make more predictions and do more and more tests, to see if the theory can get stronger yet.
- Failed Result: If the prediction did not come true, then the theory is falsified, and there are strong reasons to believe the theory is false. Nothing is ever certain (the sun may not actually rise tomorrow, for example, even though we all know it will), but we will assume that we were wrong if observations do not match our theories. When our predictions fail, we go back and devise a new theory to put to the test, and a new prediction to go with it.
Actually, a failed experimental result is really a kind of success, because falsification tells us what doesn’t work. And that frees up the scientist to pursue other, more promising theories. Scientists often test more than one theory at the same time, so that they can eventually arrive at the “last theory standing.” In this way, scientists can use a form of disjunctive syllogism (a deductive argument form) to arrive at definitive conclusions about what theory is the best explanation for the observation. Here’s how that part of the procedure works.
(P1) Either Theory 1 is true, or Theory 2 is true, or Theory 3 is true, or Theory 4 is true. (And so on, for however many theories are being tested.)
(P2) By experimental observation, Theories 1 and 2 and 3 were falsified.
(C) Therefore, Theory 4 is true.
Or, at least, Theory 4 is strengthened to the point where it would be quite absurd to believe anything else. After all, there might be other theories that we haven’t thought of, or tested yet. But until we think of them, and test them, we’re going to go with the best theory we’ve got.
There’s a bit more to scientific method than this. There are paradigms and paradigm shifts, epistemic values, experimental controls and variables, and the various ways that scientists negotiate with each other as they interpret experimental results. There are also a few differences between the experimental methods used by physical scientists (such as chemists), and social scientists (such as anthropologists). Scientific method is the most powerful and successful form of knowing that has been employed. Every advance in engineering, medicine, and technology has been made possible by people applying science to their problems. It is adventurous, curious, rigorously logical, and inspirational – it is even possible to be artistic about scientific discoveries. And the best part about science is that anyone can do it. Science can look difficult because there’s a lot of jargon involved, and a lot of math. But even the most complicated quantum physics and the most far-reaching astronomy follows the same method, in principle, as that primary school project in which you played with magnets or built a model volcano.
Doing the Scientific Method Yourself
We do the scientific method every day all the time when we learn or predict things. What will happen if you don’t text/call/message your significant other for longer than you normally do? Test it and find out! What will happen if you put 5 packets of ketchup on a hot dog? Find out! Pick some variables, make a prediction of what will happen when you change the variables, and then observe the results when you make those changes. Were you correct? What have you learned? What experiment would you like to do to test your new understandings? Follow the method mentioned in this chapter and see what you can learn.