Whoever was in charge
For most of history, “how do we know?” meant whoever was in charge.
A king. A church. Later a textbook. You were supposed to accept it. Asking was disloyalty.
The job was not to understand the world. It was to repeat the official story. If the story was wrong, you were not meant to notice. You were meant to keep the peace.
That is a stable way to run a kingdom. It is a terrible way to learn anything.
Treat it like a theory
The trick that changed that is simple to say and hard to live.
Treat those answers as theories. Guesses about how the world works. Then try hard to prove them wrong.
Not to be a jerk. To find out if they are any good.
A claim that cannot be wrong is not knowledge. It is a decree. “Because I said so,” with better stationery.
If there is no test that could sink it, it is not telling you about the world. It is telling you who is in charge.
That is not cynicism
This is not a brief for giving up. It is how we got better.
Textbooks update. Studies get challenged. Nobel Prizes go to people who overturned “settled” thinking.
Ulcers are the clean example. For a long time the story was stress and spicy food. Barry Marshall and Robin Warren said no: a bacterium, Helicobacter pylori. Marshall drank a beaker of the bacteria to force the issue. They were right. The textbooks moved.
The cards on this site are not a list of failures. They are the system working. Someone was wrong in public. Someone else checked. The story changed.
If nobody is allowed to be wrong, the story never changes. That is worse.
A useful theory says why
A useful theory says why something happens, so you can test it. You can go looking for the case that should not exist if the theory is right.
If you have to patch it with a special exception every time it fails, it is not a good explanation. It is a story you are protecting. You can always add another patch. That does not mean you understand anything.
Progress is replacing a worse explanation with a better one. Then doing it again.
David Deutsch’s The Beginning of Infinity (2011) is where that landed for this site. Not as a book to recite. As a way to look at every “fact” you were taught and ask: what would it take to break this?
The beginning, not the end
We are at the beginning of knowledge, not the end.
Every correction on this site is one step. There is no final list of facts. There is no year when we “finish” science and switch to memorizing.
The next important discovery is one we have not thought of yet. That is the hopeful part. It is also the uncomfortable part. It means the best map we have is still a map.
What this site is
This site is a catalogue of claims that were taught as fact and later replaced.
Enter a birth year on the home page and see what you were likely taught. Nutrition. History. Psychology. Medicine. Each card has sources. You can go check.
The point is not “gotcha, you were dumb.” You were not dumb. You were in a classroom, and the classroom had a story.
The point is: this is what error-correction looks like from the inside of a life. You grew up inside one set of explanations. The world moved. Some of those explanations did not survive.
That is not an insult. That is the method leaving fingerprints.
What this site is not
This site is not a new priesthood called Science that you must obey.
“Science says” is just another authority if nobody is allowed to criticize it. A lab coat is not a crown. A journal is not a church. A consensus is not a commandment.
The method is criticism. Try to break the claim. Keep the one that survives. Replace it when a better one shows up.
If a claim needs you to stop asking, it is not the method. It is the old thing in a new outfit.