"Can't prove a negative" Debunked | TranscendentPhilosop

SOURCE: https://www.facebook.com/groups/204367762908859/?multi_permalinks=3006679299344344&hoisted_section_header_type=recently_seen

On "Can't prove a negative":

To understand that free will has been disproven, we first have to understand that proving a negative is indeed very much possible and even common in science and logic.

"You can't prove a negative" is what I call pseudo-logic. Often this phrase is just used as a lazy shorthand to make clear that:

"The Burden of Proof for the particular claim that X exists, actually lies on the person making the claim that X exists, and not on the person who is skeptical of that claim."

As it would be weird to make someone who actively does not believe a claim to be the one who would have to test for it because this would be terrible for both parties, obviously. As explained by Free Will Skeptic Rationality Rules, using the "god" claim as an example:

You Can't Prove That God Doesn't Exist - Debunked: https://youtu.be/R3OkCxhjDmQ

This phrase "I can't prove a negative" should be replaced with: "The Burden of Proof for your claim is on you, not on me." Because the fact is: You most certainly can prove a negative and Logic and Science "prove negatives" all the time.

Stephen Law - Can't prove a negative? Sure you can!: https://www.psychologytoday.com/.../you-can-prove-negative

It is possible to prove specific negative claims that are made with rather well-defined limits. If the area to be searched is well-defined and of a reasonable size that permits searching then a negative claim might be capable of being proven.

"Why is it that few people seem to have problems with the burden of proof when it comes to the innocence or guilt of a murder suspect, but then cannot apply the same exact logic to more esoteric issues, such as the existence of ghosts, gods, and the like?"

- Massimo Pigliucci, 2010

For example, if one claims that there is no apple in the top desk drawer of a desk then all one needs to do is to open the top desk drawer indicated in the claim and examine it for its contents. Finding no apple therein would provide sufficient evidence under ordinary circumstances to verify or confirm the negative claim that there is, in fact, no apple in the top desk drawer.

Irving Marmer Copi (American philosopher, logician, and university textbook author.) writes:

"In some circumstances, it can be safely assumed that if a certain event had occurred, evidence of it could be discovered by qualified investigators. In such circumstances, it is perfectly reasonable to take the absence of proof of its occurrence as positive proof of its non-occurrence." - Introduction to Logic, Copi, 1953, Page 95.

You can prove a specific negative claim simply by providing contradictory evidence. An example of a proof of a rather specific negative claim by contradictory evidence would be if someone were to claim that the one and only watch that you own is in the top drawer of the desk. You make the negative claim that it is not in the drawer and you see it clearly on your wrist. There is no need to look in the drawer.

You can also prove specific negative claims when they involve known impossibilities. For example, if someone was to claim that the one and only moon that normally orbits the planet earth was in the top desk drawer. You claim that the moon is not in the desk drawer. There would be no need to look inside because the mass of the moon would not fit inside such a space and was its mass to be condensed, its mass would be far greater than the desk could support were the desk made of ordinary material.

You can also prove specific negative claims that can be rephrased as a positive claim. If someone claims that the lights are not on in room 442 that claim can be rephrased as claiming that the lights are off in room 442.

For some reason, some people believe that "you can't prove a negative" is an actual law of logic, but it's not.

A real, actual law of logic IS a negative.

Namely, the law of non-contradiction (which is important in many of the logical arguments against libertarian free will). This law states that a proposition cannot be both true and not true. Nothing is both true and false. Furthermore, you can prove this law. It can be formally derived from the empty set using provably valid rules of inference. (I’ll spare you the boring details). One of the laws of logic is a provable negative. This means we’ve just proven that it is not the case that one of the laws of logic is that "you can’t prove a negative". So we’ve proven yet another negative! Talking about negatives...

"You can't prove a negative" IS itself a negative.

If you could prove it true, it wouldn’t be true! It would be a self-defeating statement or a retortion were it not generally understood to be a limited claim. What is usually meant by the assertion that "One can not prove a negative claim" is that it is not logical to insist that a person who is not convinced by a claim carries a burden of proof for that claim.

The Burden of Proof of the claim "A is connected to B" is on the person claiming a relationship between A and B. Not on the person skeptical of that claim, who has no reason to believe it to be the case. But proving a negative can, in fact, be easily done.

So, we should stop saying "can't prove a negative." because we are to lazy to explain what we mean in language that is more accurate. I do declare. Also, Pluto is not a planet. Get over it.