How to provide a simple example to the requirement of falsifiability in the scientific method to a novice audience?

by Val 2 min read11th Apr 201658 comments


(I once posted this question on academia.stackexchange, but it was deemed to be off topic there. I hope it would be more on-topic here)

I would like to introduce the basics of the scientific method to an audience unfamiliar with the real meaning of it, without making it hard to understand.

As the suspected knowledge level of the intended audience is of the type which commonly thinks that to "prove something scientifically" is the same as "use modern technological gadgets to measure something, afterwards interpret the results as we wish", my major topic would be the selection of an experimental method and the importance of falsifiability. Wikipedia lists the "all swans are white" as an example for a falsifiable statement, but it is not practical enough. To prove that all swans are white would require to observe all the swans in the world. I'm searching of a simple example which uses the scientific method to determine the workings of an unknown system, starting by forming a good hypothesis.

A good example I found is the 2-4-6 game, culminating in the very catchy phrase "if you are equally good at explaining any outcome, you have zero knowledge". This would be one of the best examples to illustrate the most important part of the scientific method which a lot of people imagine incorrectly, it has just one flaw: for best effect it has to be interactive. And if I make it interactive, it has some non-negligible chance to fail, especially if done with a broader audience.

Is there any simple, non-interactive example to illustrate the problem underlying the 2-4-6 game? (for example, if we had taken this naive method to formulate our hypothesis, we would have failed)

I know, the above example is mostly used in the topic of fallacies, like the confirmation bias, but nevertheless it seems to me as a good method in grasping the most important aspects of the scientific method.

I've seen several good posts about the importance of falsifiability, some of them in this very community, but I did not yet see any example which is simple enough so that people unfamiliar with how scientists work, can also understand it. A good working example would be one, where we want to study a familiar concept, but by forgetting to take falsifiability into account, we arrive to an obviously wrong (and preferably humorous) conclusion.

(How I imagine such an example to work? My favorite example in a different topic is the egg-laying dog. A dog enters the room where we placed ten sausages and ten eggs, and when it leaves the room, we observe that the percentage of eggs relative to the sausages increased, so we conclude that the dog must have produced eggs. It's easy to spot the mistake in this example, because the image of a dog laying eggs is absurd. However, let's replace the example of the dog with an effective medicine against heart diseases where someone noticed that the chance of dying of cancer in the next ten years increased for those patients who were treated with it, so they declared the medicine to be carcinogenic even though it wasn't (people are not immortal, so if they didn't die in one disease, they died later in another one). In this case, many people will accept that it's carcinogenic without any second thought. This is why the example of the egg-laying dog can be so useful in illustrating the problem. Now, the egg-laying dog is not a good example to raise awareness for the importance of falsifiability, I presented it as a good and useful style for an effective example any laymen can understand)