The word Fact comes from the Latin word factum, neuter past participle of facere or ‘do’. It’s original intent was as ‘an act’ or ‘action’, particularly of evil origin, which was later used to define ‘a crime’. It survives in this old form in the still modern phrase “before or after the fact”. This old meaning lapsed in the 16th century as the word was redefined to mean “known truth”.
The current dictionary meaning of ‘Fact’ is something known to be true. The legal definition is “an actual or alleged event or circumstance”, which is a bit looser, and relies on evidence to tell the difference between “actual” and “alleged”.
We come into a sticky situation with the words “known” and “true”, mostly due to evidence and change.
For something to be known, someone must know it. I have plenty of experiences that I have shared with others, and I have others that I have not. As such, there are some things known by me that are not known by others. If I relay an experience that occurred when I was out walking as a child, I am relaying a known something from my perspective that is unknown by any other. Does that make it known? Does that make it unknown? Or perhaps a-known?
In my shared experiences with someone else, my perception of the experience may not match that of the other person who shared it with me. I may make a statement about what I know of the event that is denied by the other person. As such, what is known about this event? Is my knowledge better than another’s? Or worse?
To negate this problem, the principles of science require multiple measurements by multiple people in circumstances where another can replicate the outcomes if they meet all of the pre-conditions. I can claim that I can telelport from one location to another and that I have done so many times. Perhaps I can, but if I can’t demonstrate it to another, my accounting of it has no real meaning, as far as a scientific perspective is concerned. It might impress my friends with my story, but it will probably disturb my therapist.
If I demonstrate it to a friend, and they concur with my statements to others, will another be able to trust the two of us? The easiest way to satisfy the test is to demonstrate it. If I can teleport on demand to any reasonable people that request it (this isn’t entertainment, it’s science! – but I should be able to demonstrate it to anyone), then the knowledge of my teleportation becomes scientifically relevant, it becomes known. (How is another matter entirely!)
Truth is another problem. There are no fixed things in this universe. We would love for there to be, but there isn’t. All of our measurements of everything are taken with an error margin and an acceptance that new evidence will supersede the previous knowledge.
Take a measuring stick and place it against an object. The closest you can definitely state the object is to a measurement is half a unit of the smallest notch of your measuring stick. So if the object I am measuring comes to 2 cm and I have mm accuracy, then the object is actually 2 cm +/- 0.5 mm (this varies depending on the measurement and the equipment). It is our confidence with the equipment we have to measure. Another way to consider this is imagine you are trying to measure Pi. I have a stick that is exactly Pi cm long. I try to measure it with my measuring stick and I will get 3.14 cm, +/- 0.5 mm, or 0.005 cm. I can’t get any closer to the number Pi with that stick, because it isn’t any more accurate than that. This doesn’t mean that pi is 3.14 cm, or 3.135 cm, or 3.145. It means it is between 3.135 cm and 3.145 cm, but not lower 3.135 cm and not greater than 3.145 cm. A more accurate method of measuring will generate a more accurate result.
As I grew up, it was theorised that a planet may revolve around a star somewhere in this universe, hopefully this galaxy, that had an Earth like planet. We knew of only one planet that fit the bill, and I was born on it, and that was the truth. Maybe there was another – but we had no evidence of it, just a possibility, so there was no truth to a statement such as “an Earth like planet orbits around another star” – because we had no evidence it did, or that it could. A few years ago it was announced that exo-planets had both been detected in space and also in orbit around other stars. The possibility of an Earth like planet increased, although none had been found. After all, we now had evidence, not just a hypothesis, of a planet around another star! There was still no truth to the statement “an Earlth like planet orbits around another star”. It was just a matter of time, we hoped, to find an Earth like planet.
Today I read an article that said we have found Gliese 832 C, a super Earth and the current best candidate as “Earth like planet” in a habitable zone around the star Gliese, only 16 light years away. It’s orbit is measured in 36 Earth days – that’s it’s year vs ours of 365 Earth days. Today this is the new truth. That is, new evidence has superseded the old truth of “we know of no Earth Like planet orbiting another star” with “we know of an Earth like planet orbiting around another star”. This is the best candidate for life on another planet around another star and it is measured in several ways. The planet is bigger than Earth, but not too much. It is closer to it’s star (a red dwarf), but well within the habitable region of energy from the star (closer because it is a red dwarf). While there are two other contenders for the “best”, Gliese 832 C wins because it is the closest planet we have found.
If we were to find another planet that was more Earth like only slightly further out, it may defeat our measure of “best”, especially if we detect intelligent life on it. This is the nature of truth. It changes as we learn more. And what we learn is based on what we know.
Coming back to facts. A fact is something that we “know” to be “true”. Know requires many people knowing about it for it to become knowledge, and knowing about it means being able to verify that it is true as far as we can test, but allows for new evidence to change what is true.
The more we know, the more facts become wrong. The opposite of a fact is not fiction. That’s just a library convention and implies an intent to deceive. Tells you a lot about librarians, doesn’t it. Or is that more authors? Superseded information has no intent (we hope) to deceive.
So what is unchangeable Truth (note the capital T)? Some believe they find it in a god, or a certainty that they have about something, such as no humans ever having reached the Moon. There are two conflict of Truth versus truth.
The first has to do with “truth is verifiable”. You can run a test, that is anyone can run a test, and get the same or very similar result. That gives us the truth. As I grew up, no matter who looked through the telescopes, no one saw a planet around a star other than ours.
The second has to do with the variable nature of truth. That is, truth can be superseded with a newer truth. Anyone that looks at the data can verify the calculations and the observations and demonstrate that Gliese 832c is indeed an Earth like planet approximately 16 light years away. This is a new truth. This doesn’t make the old truth a deception, it just makes it wrong, however at the time it was the best truth we had.
Gods cannot be verified by tests. Nor can a certainty about something, such as the idea that man has not been on the Moon. Both of these types of Truth require belief instead of evidence. After all, no new evidence will allow for a believer of these Truths to adjust their idea of what is real and reject their Truth. As such Truth is not truth.
Superseded facts are not necessarily wrong either. If I give you a the fact that this object is 3.14 +/- 0.005 cm in length, then measure it with a better tool and discover that it is 3.14156 +/- 0.00005 cm, then my first measurement, while inaccurate, is not really wrong. If my more accurate measurement were to give me 6.282 +/- 0.0005 cm, then I would certainly consider my first measurement as wrong while my new measurement is right (so long as the new measurement isn’t the wrong one… and science is basically all about checking which measurement is the right and the wrong one!). In the first now inaccurate measurement of 3.14 vs 3.14156 (let us call this “A”), the ratio is minimal. In the second one 3.14 vs 6.282 (let us call this “B”), the ratio is huge. A is supporting previous evidence with a greater degree of fidelity, while B is conflicting with previous evidence – one of them is clearly wrong.
In re-measurement A, to suggest that 3.14 was wrong may be to commit a logical fallacy. That is to ignore the point of the discussion because a single point is not accurate enough. To assert the same point if B was our second measurement would be fair enough because the ratio is way out.
To summarise, a fact is something that is accurate at the time of writing or stating. It is accurate because it is a knowledge based on evidence and tests. It can be updated as new evidence and tests are created and used. An old fact should be out by a significant ratio to be considered out right wrong, rather than less accurate.