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.
Something being falsifiable and something being universally possible to check are 2 different things.
In theory you could falsify that statement after checking only a single swan if it happens to be a black swan.
Conservation of energy is falsifiable. If you found some way of creating energy without taking it from elsewhere then you would falsify it. However it isn't practical to check every cubic meter of space in the universe to check if it applies everywhere.
there's also the old Invisible Dragon example from Sagan
“A fire-breathing dragon lives in my garage.”
Suppose … I seriously make such an assertion to you. Surely you’d want to check it out, see for yourself….
“Show me,” you say. I lead you to my garage. You look inside and see a ladder, empty paint cans, an old tricycle—but no dragon.
“Where’s the dragon?” you ask.
“Oh, she’s right here,” I reply, waving vaguely. “I neglected to mention that she’s an invisible dragon.”
You propose spreading flour on the floor of the garage to capture the dragon’s footprints.
“Good idea,” I say, “but this dragon floats in the air.”
Then you’ll use an infrared sensor to detect the invisible fire.
“Good idea, but the invisible fire is also heatless.”
You’ll spray-paint the dragon and make her visible.
“Good idea, except she’s an incorporeal dragon and the paint won’t stick.”
And so on. I counter every physical test you propose with a special explanation of why it won’t work.
Now, what’s the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all? If there’s no way to disprove my contention, no conceivable experiment that would count against it, what does it mean to say that my dragon exists? Your inability to invalidate my hypothesis is not at all the same thing as proving it is true. Claims that cannot be tested, assertions immune to disproof are veridically worthless, whatever value they may have in inspiring us or in exciting our sense of wonder. What I’m asking you do comes down to believing, in the absence of evidence, on my say-so.
What I don't get is: They never take swords, they never check for princesses. Don't they know that curiosity kills 95.234% of cats?
(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)