## Difference Between Verification and Falsification

Posted by allzermalmer on September 30, 2012

Karl Popper developed the idea that the demarcation between empirical statements, which was mostly taken to be scientific statements, and metaphysical statements was based on the idea of falsification. Popper was speaking out, or presenting, a different criterion to differentiate between empirical statements and metaphysical statements.

“The problem of induction arises from an apparent

contradiction between the basic empiricist requirement(only experience can decide the truth or falsity of a scientific statement) and Hume’s insight into the logicalimpermissibility of inductive decision(there isno empirical justification of universal statements). This contradiction exists only if we assume that empirical statements must beempirically “fully decidable”,that is, that experience must be able to decide not only their falsity, but also their truth. The contradiction is resolved once “partially decidable” empirical statements are admitted: Universal empirical statements are empiricallyfalsifiable, they can bedefeated by experience.” The Two Fundamental Problems of the Theory of Knowledge

Verification meant that empirical statements, or scientific statements, are those that it is possible be decided to be true or false by experience. You can fully decide that the statement is true because experience has shown the statement is true. Like experience can show that “this apple is red in color”, so too can experience show the statement that “all apples in the refrigerator are red in color”. The refrigerator is in a specific place, at a specific time, and logically possible to see if all the apples in the refrigeration are red in color. It can be opened and found that all the apples are red in color, or that all but one of the apples in the refrigerator are red in color, like one can be yellow. Thus, it is both logically possible to empirically verify the statement or empirically falsify the statement. It is logically possible to either show it is true or show it is false.

However, the statement that “all apples in refrigerators are red in color” is logically impossible to empirically verify. This is because this universal statement applies to all times and all places, while the previous universal statement applies to a specific time and specific place.Thus, this universal statement cannot be verified, but it can still be empirically falsified. You might not be able to check all the refrigerators that will, or have, existed in all places or all times, but those that you have observed have the empirical possibility of showing the statement to be false. You might not be able to check all refrigerators in all places and times, but finding a specific refrigerator that has a yellow apple, shows that all refrigerators, in all times and place, do not have all red apples in them. One case has been found to run counter to the universal claim. Thus, we learn that some refrigerators have only red apples in color and some refrigerators have yellow apples in color.

The point becomes that science can introduce whatever universal statement it wants, so long as it is logically possible to make one empirical observation to show it is false. We do not have to show that what it introduces is true by experience, just that it can make predictions that are logically possible to show false by experience.

Let us imagine that there is a person who walks amongst us, and this person knows all the laws of nature. Let us also assume that it is a trickster like Loki. It mixes some truth with some falsity, knowingly. It decides to come up with a falsifiable statement, which means that it is not fully decidable, i.e. it is partially decidable. It knows that this universal statement is false, but it still makes predictions that are possible to be shown false by experience. This being that is like Loki knows that all attempted experiments to show that statement is false by experience will fail, which means it passes every single experimental test that can be presented. You would be justified in accepting a false statement because you cannot show it is true but you can show it is false.

## pauladkin said

I can prove by daily observations and experience that the sun most definitely revolves around our world.

## allzermalmer said

“It is often asserted by contemporary physicists that it was discovered in the 15th century that the Earth revolves about the Sun, and not vice versa. This statement is not extended to say what Galileo discovered — that motion is subjective and thus that it is as equally true to say that the Sun revolves about the Earth as it is to say that the Earth revolves about the Sun!” Physicist Mendal Sachs

## Daisy said

Forgive me if I have misunderstood Poppers method of deductive falsification.

I form a conjecture that life exists on Kepler 22 b. Lets imagine a future scenario which allows me to travel with ease to Kepler 22 b. It is true that my conjecture can be easily falsified by arriving there and finding no signs of life on the planet. But is it not also true that If I arrive there and find life on the planet my conjecture has been verified? Does Popper not suggest that a scientific theory can never be truly verified but falsified or have I somehow misunderstood? I know this was posted a while ago but would love to be enlightened on this matter

## allzermalmer said

The existential propositions we make, like There exists at least one x, such that x is life on Kepler, has a variable with a predicate. This predicate deals with dispositions, i.e. organism that can have two legs or hands and carbon based. These all deal on a universal level, so you can’t verify a single thing has a property, i.e. a disposition, through a single observation. All you can do is say that the observations you collected on the plant, that seem to be consistent with the conjecture, isn’t falsified yet. Not being falsified doesn’t mean it isn’t false.

An example is trying to make a proof by contradiction. In this case, we assume that the hypothesis is true and try to derive a contradiction. Now this type of proof will involve all sorts of observations of the past and observations into the future. We don’t have all those observations yet, and so the proof continues by assuming hypothesis is true and trying to derive a contradiction from it with each new observation made. Since we haven’t obtained that contradiction yet, it doesn’t prove that the hypothesis is true. It just means haven’t gotten to a line of the proof that has the contradiction in it.