Opinion vs Fact

Question

How do I know if a piece of infromation is a fact or an opinion?

I read that facts can be proven while opinions can't, but for example if I say: "It is hot!":

It can be proven whether I'm really hot or I'm lying by observing sweat. Then all opinions can be proven; So, there are no opinions.

I also read that facts are absolutely accepted while opinions are relatively accepted, but for example if I say "Earth is an irregularly shaped ellipsoid.":

Some people will accept this, while some will reject it and accept that earth is flat. Then all facts will not be absloutely accepted; So, there are no facts.

Answer 1

Few philosophers seem to have bothered with this particular distinction (as opposed to many lawyers). As a philosophical question it's confounded by several problems: fact vs. statement of fact, fact-value distinction, objective/subjective reality etc.

According to (American philosopher) John Corvino, one way to at least be less confused is to see the distinction as:

• A statement of fact is one that has objective content and is well-supported by the available evidence.

• A statement of opinion is one whose content is either subjective or else not well supported by the available evidence.

You still have to decide on those sub-criteria, which is not necessarily an easy task, depending on your philosophical standpoint on the sub-problems. (Well, he does assume a subjective/objective distinction is possible, just like most lawyers do).

But don't go to a court with this def. Because if you state a wrong fact about someone (meaning judged to be intended as statement of fact, but not a fact, i.e. false by the court), you're definitely much more likely to be liable for defamation than if you state a subjective opinion (in the court's view). In other words, the lumping of the two or-ed categories in the last bin (by Corvino) may be dangerous to your legal outcomes. But the lumping is reasonable for everyday use of the retort "it's [just] your opinion!" Corvino exemplifies the final sub-category of the 2nd bin with a statement like "God exists".

To give you a concrete example of a controversial case law (in the US), a statement about someone having "no status within the profession" was judged 6-5 to be a matter of opinion rather than a (false) factual statement. (No less than 3 separate standards for the distinction were offered by the Appellate judges.) SCOTUS denied certiorari, but two of the Supreme Justices felt like writing our their dissent nonetheless (which doesn't often happen in certiorari denied cases.)

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Somewhat of an aside: according to (American philosopher) Norwood R. Hanson, statements of fact can never be false, only factual statements can be so. (But to me this sounds more like pedantry about language... I have no idea if other philosophers follow this prescription.)

Answer 2

Consider Hume's Fork.

A statement that falls on the analytical side of the fork is a fact. It is an analytical fact. Triangles have three sides. This is a statement that is true by definition. Statements of this kind would require us to doubt our own sanity in orde to doubt the statement.

A statement on the synthetic side of the fork is contingent on the particulars of reality. Such statements can be objective, or they can be opinion. Either of these can be true or false.

An objective statement would be one such as: drinking water is required for a human to live. This statement is subject to empirical verification. It is objectively true, since sad experience has shown that when a human cannot get water to drink they die.

Objective statements can be false. Example: It is not possible for humans to fly faster than the speed of sound.

A statement can be objectively true based on current evidence, but false in reality. Easy examples abound. "Powered human flight is impossible." This statement was true before powered flight methods were developed. Yet, powered flight is possible.

Opinion comes in flavors. (Of course, you see what I did there.)

One such is statements of preference. "The best kind of food is char-broiled steak." "American football is the best sport." "Luke Skywalker is the best Jedi."

Another type of opinion is a statement based on minimal or insufficient evidence. "This skull fragment is from a tyranosaur." A paleontologist may examine a fragment of skull and give his opinion that it is from a particular type of dinosaur. However, such opinion necessarily has a component of uncertainty. It should usually be expressed in a way that includes the uncertainty. For example: "I estimate that it is 90% likely this skull fragment is from a tyranosaur." Or another: "The DNA test gives a 99% chance that this man is not the father of this child."

The boundary between opinion and objective fact is not sharp. This is highlighted by the previous paragraph.

Answer 3

It depends on what school of epistemology you subscribe to.

If you follow Rene Descartes, you'll find that the only thing you can ever truly prove is your own existence. ("I think, therefore I am")

The most common view is that a fact is something with empirical evidence supporting it. E.g. "This book is long" is subjective; people perceive a book's length differently. "This book has 835 pages" would be fact; pages can be measured.

In this sense, a fact is only a fact if it can be completely measured and has no basis in subjectivity.

For a quick overview of many schools of epistemology, check this wiki page, it may help you narrow down what you're looking for here.

Answer 4

I read that facts can be proven while opinions can't, but for example if I say: "It is hot!"

The statement "It is hot" is an opinion or a qualitative statement. The statement "It is 98.6° Farenheit" is a quantitative statement that can be established as fact since it can be independently verified with a thermometer. Whether 98.6° is hot, is a matter of opinion.

Another scenario is two people meet and swim in water that is 68°. The first person grew up swimming in the Pacific Northwest swimming in water that was 60°, the other grew up in Miami swimming in water that was 75°.

The water is 68° Person 1 says "Wow, this water is warm!" Person 2 says "Wow, this water is cold!"

Which information is fact?

Answer 5

Hi if something is a fact it is to do with how it relates to the world separate from us. So facts and opinions are different concepts, opinions can be about facts but a fact is true anyway. Facts are to do with truth and truth is to do with the objective world.

Answer 6

You - and many answers - are assuming that "fact" and "opinion" are two distinct categories. They are not. One is not the opposite of the other and they are not exclusive. Most examples given here are overly simplified and don't do that justice.

In many longer discussions about what a "fact" actually is - such as this one - the word "opinion" never appears.

A fact is generally considered to be something "in the world", objective, measurable in some way, something for which a truth value can be established, at least in theory. Think "fact-checking".

Whereas an opinion is a mental state. A belief someone has about something. That belief can be identical to a fact. In a murder case, you can have an opinion about whether the accused is guilty or not. That opinion may or may not align with the facts (and we may or may not actually prove the facts).

Note that most everyday speech is shortened, with implied content that isn't spoken. When someone says "it is hot", the full statement, if you could convince them to state in full the meaning of it, would be something like "I feel that the temperature today is well above what I consider average." - and spelled out in full, this is getting close to something that could be factually checked. However, that isn't the difference. Many opinions could be fact-checked. What makes them opinions is that they are a personal, internal experience.

So you have the "fact" - part of the world - and the "opinion" - part of the subjective experience. About the first we can argue, observe, measure. About the second we cannot - that I disagree with your opinion is simply a different opinion, but there is nothing exclusive about it. Either, neither or both of our opinions could be true-to-facts as well, or be unknown or undeterminable with regards to that. A specific statement can be both fact and opinion. If the distinction is important, you need to make it explicit. Language being the murky thing it is doesn't always do that automatically.

Answer 7

From a simplified philosophical perspective, science is what allows splitting what is objective (facts) from what is subjective (belief). Science is not only made by those people working at the CERN: you can do science at home. Read about the scientific method, and you will know how to do science. With time, it will be easier to determine if a judgement is a fact or an opinion.

Regarding the quotes, a person might sweat while other doesn't under the same conditions. So, "it's hot" is not easy to determine objectively, as a fact. You can propose a simplist solution:

• A precise temperature, like 30.0 deg, is the starting point of "hot", (NOT strictly the best solution*, but can work most of the times).

* You risk falling into the Sorites Paradox: 29.999999...deg (nines till the infinite) will be cold, and 30.000000... deg will be hot, while they are exactly the same number!

Answer 8

A fact is a statement proven to be true.

A statement proven to be false is a lie.

A statement of unknown truth value is a belief, a piece of fiction or a hypothesis.

An opinion has no truth value. An opinion is a moral or personal judgement about whether something is good or bad, right or wrong.

Answer 9

"It is hot!" is an expression of experience, relative to (presumably) your own opinion of what counts as hot.

Hot according to whom? A person from the Arctic Circle spending time in summertime France may declare it's hot, but a person from the Sahara may disagree.

Meanwhile, I would dispute that a fact is a "proven" thing. It is merely an observed thing. And even then, it is observed by degrees and gradients according to what it is measured with. The word "proven" implies a standard of truth has been reached - for example, physicists may give a fact with an error margin or estimated certainty value.

Instead of saying it is hot, if you want to be factual, you may want to say how hot. So you say it's 30 degrees Celsius. This is better, but then still according to whose thermometer?

Similar for your sweating example - how much are you sweating in millilitre per hour? Is that a lot? What is a "normal" amount of sweat?

Any datum, whether fact or opinion, only has meaning when compared to, or in the context of another datum. A datum about ambient heat is compared either your opinion of what's too hot, or a thermometer value which presumably has been standardised in some way.

Answer 10

Limiting us to people that accept logic as the only way to search for truth, and limiting again to sincere people, and limiting us to people that know and manage correctly logic laws, a fact is an opinion thought to be true, until demonstrated to be false. So e.g. classical mechanics was believed to be true, and fact until demonstrated to be false. So I would take the relative point of view, opinions that are considered with high probability to be true may be called facts until proven false. Low probability true facts are opinions. By that though, I may have two opposite opinions or more but not too opposite beliefs of facts ( I cannot believe at the same time with probability 99% 2 opposite facts unless there is doubt on them being opposite).

Answer 11

There is a problem with the original statement. The statement is trying to making a logical, deductive proof. The problem is that the second sentence has taken one statement of fact and declared it to be the applicable to all cases without setting the proper local basis. Therefore, the validity of the conclusion is unknown under standard logic.

What that person did was this: If A is true, then B must be true. Therefore C is true. They need to establish why B logically follows from A and not just assert it. They also need to establish why C follows from B.

Answer 12

This all comes down to your definitions. First of all, your definitions of the words "fact" and "opinion", of course. But then, also the intended meaning of the words in question.

For example, the words "it is hot!" can have quite a few interpretations:

• It can state the fact that a machine is too hot to be touched.

• It can state the fact that temperatures 40°C are uncomfortably high.

• It can state the opinion that 25°C are uncomfortably high.

• It can be irony spoken in the middle of a snow storm.

• It can be a lie used to cover up the fact, that someone is impersonating somebody else in a hot country. All the while snowflakes are falling outside the impostors window...

• It can state the fact that a part of cryogenic appliance is at room temperature.

• ...

There are all kinds of shades of grey involved here, all of which come down to the precise intended meaning of the words. And that may not even be possible to deduce. Like when a poet deliberately uses ambiguity of meaning. In other contexts, words that are generally not precise may have a very well-defined meaning. For instance, when you hear talk of a cold magnet in some scientific context, it invariably means that the magnet in question is a superconducting magnet that needs to be cooled to cryogenic temperatures for operation. You may not have heard of this use of the word "cold" yet, but within the context, it has this exact meaning.

Only once you have established the intended meaning of the words, you may continue to analyze whether they are fact or opinion. And this is simple, in principle: Facts are opinions with evidence behind them. If you want to check whether an opinion is actually a fact, you must check the evidence. There is no other way. You can try to offload the burden of fact checking to other people whom you trust, but in the end, someone has to do the work. And other people's opinions are but hear-say evidence to you! So, when you do trust other people, do yourself a favor and make a mental note that you are trusting in hear-say.

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This post contains the opinion of the author. Does it contain facts? This question is left as an exercise to the reader.

Answer 13

If there was life on Mars two billion years ago, then the fact that there was such life is a fact, but is not known to us today to be a fact, but a scientist may be of the opinion that such life existed. So that is both a fact and an opinion. They are not mutually exclusive.

Answer 14

To take your flat earth example, physical facts can be proven beyond reasonable doubt. The problem comes with statements like:- "All human beings are equal under the law". In earlier times, this was an opinion which was not supported by experience. However, it is no longer considered an opinion - but a fact in law in most jurisdictions. So, some opinions become facts over time, while others are forgotten.