Absence of evidence IS evidence of absence

[Keith&Co.]

Evidence, broadly construed, is anything presented in support of an assertion. I’m not the one confusing “in support of” with “that guarantees the truth of.”

Well, yes, you are, in not making a clear distinction between the actual facts and opinions about facts.
You're actually posing, and defending, more of a bait-and-switch approach.


Maybe a diagram would help?
Can you draw those circle things to show what you're talking about, with a person's point of view as opposed to the unknown but all-encompassing facts of a matter?

 

[Keith&Co.]

Many people here take the word "evidence" to refer to something like an absolute proof. They think that there could be evidence of Bigfoot only if Bigfoot existed.

No, THAT isn't the problem here. The way he constructed the story problem, he wants to simultaneously have complete knowledge that there are none bigfoots AND evaluate possible evidence for the same mythical bigfeets.

This is like wondering why the hero in a Hitchcock movie is not acting on knowledge that only the audience has.

 

[Speakpigeon]

Many people here take the word "evidence" to refer to something like an absolute proof. They think that there could be evidence of Bigfoot only if Bigfoot existed.

No, THAT isn't the problem here. The way he constructed the story problem, he wants to simultaneously have complete knowledge that there are none bigfoots AND evaluate possible evidence for the same mythical bigfeets.

This is like wondering why the hero in a Hitchcock movie is not acting on knowledge that only the audience has.

OK, sorry, my mistake.

So, you agree that given what the word evidence means, it's possible, even a routine situation, that we have some definite evidence that some particular thing, object or event, is real, and that everybody agrees that it is good evidence that this thing is real, and yet that this thing isn't real at all?
EB

 

[Keith&Co.]

Many people here take the word "evidence" to refer to something like an absolute proof. They think that there could be evidence of Bigfoot only if Bigfoot existed.

No, THAT isn't the problem here. The way he constructed the story problem, he wants to simultaneously have complete knowledge that there are none bigfoots AND evaluate possible evidence for the same mythical bigfeets.

This is like wondering why the hero in a Hitchcock movie is not acting on knowledge that only the audience has.

OK, sorry, my mistake.

So, you agree that given what the word evidence means, it's possible, even a routine situation, that we have some definite evidence that some particular thing, object or event, is real, and that everybody agrees that it is good evidence that this thing is real, and yet that this thing isn't real at all?
EB

Yes, I do. There's plenty of abandoned scientific theories that were developed based on evidence they had at the time. Additional evidence has been found, requiring better theories, but the original evidence never went away.

We just don't have absolute conclusions available to use as yardsticks for evaluating the evidence being presented. Except in thought experiments...

 

[Koyaanisqatsi]

Evidence, broadly construed, is anything presented in support of an assertion.

As Keith pointed out, that isn't the issue. You had stipulated absolute conditions. Which is why I said (emphasis added):

There can be something that others mistake for evidence of something you did (but actually did not do), but if you did not, in fact, do something, then there cannot be any evidence that you did, in fact, do something.

You’re confusing perceptual mistakes with objective evidence.

You do it again here:

You have bank video surveillance supporting the assertion I robbed a bank

But if we already know that you did not rob the bank--i.e., it is stipulated in the hypothetical, as you did previously--then we know that the evidence could not support such an assertion.

NOW, however, you are removing absolute certainty and proposing an entirely different hypothetical:

You have evidence that I did rob a bank, and I have evidence that I did not rob a bank.

False. I have evidence that I think depicts you robbing a bank, not evidence that you did rob a bank. It could not be you in the video, however, because you were in lock up at the time and that's corroborated, so that necessarily means I am mistaken in my perception that it is you in the bank video.

Your evidence supports the assertion irregardless of whether the assertion is true.

Now you are diluting the term "supports." Supports and "prove" are generally considered to be the same thing in a colloquial sense, with "supports" being a less concrete term. Regardless, all you have done in saying something like, "I have evidence in support of my assertion" is turn the focus on the type of evidence and how definitively (or not) it "supports" your assertion.

Iow, and once again, you are shifting the focus onto your ability to properly discern whether or not the evidence you do have is in fact evidence that proves you assertion. You've kicked it up a notch and turned focus on the evidence.

That’s what it means to be evidence, not that it guarantees the truth of the assertion but rather if it supports it.

Wrong again. Evidence is supposed to guarantee (aka, "prove") the truth of an assertion. So the question is always, how good is the evidence? Does it prove an assertion; to move beyond assertion and into "truth" or "fact"?

An assertion is essentially a strongly held belief. The strength of the evidence is what shifts that from a belief to a fact. Or not.

 

[Kharakov]

Evidence of an absent mind is evidence of absence of an idea.

 

[Lion IRC]

This guy is so bad at logic that I could probably say;
"The absence of evidence that God doesn't exist is evidence that He DOES exist"
...and get away with it

Er, no, you won't. You're guilty among other things of special pleading.

And special pleading is a sin against God, if you want to know.

Special pleading
2. The presentation of an argument that mentions or emphasises only favorable aspects of the question at issue.

See?

No, special pleading is claiming an exemption that one wouldn't grant in the case of one's opponents propositions.
A hall pass. A gimme. No evidence required...(please, pretty please, just this once?)
Things which come into existence have a cause...

Because here are the facts:

1. The absence of evidence that God doesn't exist is evidence that God exist

2. The absence of evidence that God exists is evidence that God doesn't exist.

Proposition 1 and 2 are both correct.

See?

Now, wash your mouth and go to confess.
EB

If you were my logic tutor I would believe that;
The absence of evidence for atheism is evidence FOR the existence of God.
The law of excluded middle has been nullified. Non-evidence = evidence.
The argument from silence is no longer a logical fallacy.

 

[fromderinside]

Lion IRC invokes the philosophical rule gag.

 

[fast]

We’re standing outside on a bright sunny day with no clouds in sight. The automatic lawn sprinkler cuts on, and we all know the reason for the water falling on our heads is because of the water sprinkler. Joe makes the assertion, the absurd assertion, that it’s raining. Someone speaks up and says, what can you present to support that assertion? He says, “I have crayons in my car.” That is presented for the purpose of supporting his assertion. Another exclaims, “there is no relevance between having crayons in your car and rain.” So, despite that it was brought forward for the purpose of supporting his assertion, no one wants to accept the irrelevant facts as evidence for the assertion.

Fine, but Bob speaks up and says, “the ground is wet.” That’s actually consistent with rain. Had it been raining, it would be expected and consistent for the ground to be wet. That actually supports the assertion. Quite obviously, it doesn’t prove the assertion, and besides, we all know it’s not raining and that the cause of the ground being wet is the sprinkler and not rain.

There is clear and indisputable evidence for why the ground is wet, but the issue isn’t how easily defeated the extremely week evidence is but rather it’s actual status as evidence. Both the facts “crayons in the car” and “the wet ground” are presented for the purpose of supporting the assertion, but while one fails to support the assertion, the other succeeds.

Successfully supporting an assertion is not remotely the same as successfully proving the assertion true. We know, and quite well, that the assertion is false, but knowledge of that fact has no bearing on whether the assertion is supported—not to be confused with proven without mistake.

There is often supporting evidence that fails to guarantee the truth of an assertion. Consistency is sufficent. Small tracks the size of mice may be brought forward and presented as evidence for a gigantic Sasquatch, but while it might be okay to dismiss such a presentation as evidence because of inconsistency, it would be inaccurate to deny the presentation of very large tracks as being evidence because it’s consistency stands good for support; knowing full well there is no Bigfoot doesn’t alter the status of the tracks as evidence; instead, it speaks to its strength. The facts that allow for us to know there is (oh say) no big foot in this cage at this moment overwhelmingly diminishes the strength of the evidence but not it’s status as evidence.

The crayons nor the mice tracks support the assertions, but the wet ground and the large tracks do. Prove the assertion, no. Nor does the knowledge of the truth demonstrate an inconsistency for the support both have.

 

[Wiploc]

I'm not on the side of the people who say you can't have evidence of something that isn't true.

I believe gods don't exist, but even if I'm right that doesn't mean evidence of gods is impossible.

Take Fast's example of the wet sidewalk. That would be some evidence of rain if we didn't know anything else. But we do know, in that example, that the sky is clear, and that the lawn sprinkler accounts for the wet pavement.

Thus, in the end, after looking at the evidence available, in spite of the wetness of the sidewalk, we have no reason to believe it is raining.

This is what I mean when I say there is no evidence for gods: If something is presented as evidence for gods, and the case for that claim is examined, the proposed evidence never--in my experience--turns out to be something that tilts us toward believing in gods.

Duane Gish said that there is no fact--real or imagined--which cannot be used as evidence that Jehovah exists. So, according to Gish, if a god shows himself, that is evidence of god; and if a god doesn't show himself, that is also evidence of god.

That kind of "evidence" is worthless. And, as far as I know, theists have nothing stronger than that.

 

[Speakpigeon]

Er, no, you won't. You're guilty among other things of special pleading.

And special pleading is a sin against God, if you want to know.



See?

No, special pleading is claiming an exemption that one wouldn't grant in the case of one's opponents propositions.
A hall pass. A gimme. No evidence required...(please, pretty please, just this once?)
Things which come into existence have a cause...

Because here are the facts:

1. The absence of evidence that God doesn't exist is evidence that God exist

2. The absence of evidence that God exists is evidence that God doesn't exist.

Proposition 1 and 2 are both correct.

See?

Now, wash your mouth and go to confess.
EB

If you were my logic tutor I would believe that;
The absence of evidence for atheism is evidence FOR the existence of God.
The law of excluded middle has been nullified. Non-evidence = evidence.
The argument from silence is no longer a logical fallacy.

Obviously, you're incapable of articulating your point.

Logic is about propositions, and the truth and falsehood of proposition, and the relation of necessity and possibility between the truth and falsehood of different propositions.

Here, all you can get yourself to do is post just one proposition, i.e. "Non-evidence = evidence". You can't argue anything by considering just one proposition. Still, I'm sure whatever I say will wash over your lovely feathers.

It should also be evident to you that my "absence of evidence is evidence of absence" isn't at all the same thing as your "Non-evidence = evidence". It's evidently formally different, so if you want to claim it's the same thing, you'd have to provide a logical argument in support. But it seems you don't even know what arguing logically is.

Keep going.
EB

 

[Speakpigeon]

LOGIC, lesson 1 - The law of excluded middle

The law of excluded middle has been nullified. Non-evidence = evidence.

You clearly don't know what the law of excluded middle says.

Here it is:

In logic, the law of excluded middle states that for any proposition, either that proposition is true or its negation is true.
https://en.wikipedia.org/wiki/Law_of_excluded_middle

So, explain to us all which proposition exactly we are talking about, and how what I said violate the law of excluded middle.

Clue 1: the expression "evidence" is a term, not a proposition, and as such it's neither true nor false.

Clue 2: the expression "non-evidence" is a term, not a proposition, and as such it's neither true nor false.

Clue 3: the equation "Non-evidence = evidence", although it is a proposition, which therefore may be true or false, it is not a logical argument.

Clue 4: your proposition "Non-evidence = evidence" is not the same as my proposition "absence of evidence is evidence of absence".

So, for now, you have yet to articulate what may be your argument, although by now it's clear it can't be anything like a logical argument.
EB

 

[Speakpigeon]

OK, sorry, my mistake.

So, you agree that given what the word evidence means, it's possible, even a routine situation, that we have some definite evidence that some particular thing, object or event, is real, and that everybody agrees that it is good evidence that this thing is real, and yet that this thing isn't real at all?
EB

Yes, I do. There's plenty of abandoned scientific theories that were developed based on evidence they had at the time. Additional evidence has been found, requiring better theories, but the original evidence never went away.

We just don't have absolute conclusions available to use as yardsticks for evaluating the evidence being presented. Except in thought experiments...

So, do you accept that absence of evidence is evidence of absence?

And if not, why? (please don't ask me to read the entire thread)
EB

 

[Speakpigeon]

Absence of evidence is evidence in some cases.

Take a tri-omni god: It has the power to prevent all suffering, it knows how to prevent all suffering, and it wants to prevent all suffering.

If that god existed, there would be no suffering. The fact that suffering exists is absolute proof that tri-omni gods don't exist.

But that lack of evidence says nothing against the existence of deist gods. They wouldn't be expected to leave evidence, and therefore the lack of evidence says nothing about whether they exist.

But isn't the suffering we know exists positive evidence of the inexistence of any God capable and willing to prevent suffering?!

The fact that I don't see any invisible god isn't evidence that there isn't such a god.

So, I would rather say: Absence of evidence is NO evidence in some cases.

Still, in this particular case, no invisible thing is any omnipotent being. So, absence of evidence of any invisible god is evidence there is no such god.

So, I would rather say: Absence of evidence is NO evidence in some cases although not for invisible gods.
EB

You can make this argument, but it lacks any real practicality. It's the invisible dragon in my garage argument.

I think you didn't read properly, although I grant you it's a curved ball.

It's actually similar to deism. They don't really make any claims about what the universe/gods want, that they influence the world/universe, so who gives a fuck if they want to believe it.

The reason the abrahamic religions get so much pushback is purely a reaction to their pushiness and insistence that others follow their beliefs. If they all just followed their own beliefs and left the sensible people alone, forums like this probably wouldn't exist.

Sure, but we're not discussing whether believers are pushy, we're discussing whether absence of evidence is evidence of absence. That is an issue well beyond what believers do.

It's the invisible dragon in my garage argument. Sure, it might be there, you can believe it's there all you want, but the utter lack of any kind of evidence means that even if it does "exist" in some way, it doesn't interact with the known, measurable world, so what's the point?

Who would know that the dragon doesn't interact? That you don't see something is no evidence that it doesn't interact. We don't see neutrinos and they do just about interact.

So, first, that you can't see an invisible dragon isn't evidence that there isn't such a dragon. That much I would agree if that's what you would want to insist on.

Yet, I will myself insist that the absence of any evidence that there is an invisible dragon eating the little children for lunch is evidence there isn't such a dragon.

And the point must be, surely, that we can feel reassured to have evidence that there is no dragon eating the little children for lunch. No need to spend hours debating this, it's just what we do and it seems very useful. We can go about the business of the day without having to worry about the little children being eaten by an invisible dragon.

Sorry, it's still somewhat of a curved ball, but.
EB

 

[Speakpigeon]

So, absence of evidence is evidence of absence; just don’t confuse such evidence as implying some kind of undeniable guarantee.

Did i miss the post where someone made that claim?

Yes, here someone did:

I still think absence of evidence is evidence of absence.

It's self contradictory

And again someone else, here, although with the deviousness the dude is prone to:

Absence of evidence is absence of evidence.

Well, when fast and I say that absence of evidence is evidence of absence, we mean that it is literally so and therefore not at all "self-contradictory". That's the point.

I have yet to see them articulate a logical argument but I accept it's not your point, and it's a relief in this brutal world.
EB

 

[Learner]

Sure, but we're not discussing whether believers are pushy, we're discussing whether absence of evidence is evidence of absence. That is an issue well beyond what believers do.

"Absence of evidence is evidence of absence" is not beyond what believers do, if you're taking from the POV that this issue wouldn't be the right proposition for believers to use.

 

[Keith&Co.]

So, do you accept that absence of evidence is evidence of absence?

Yeah, evidence towards, not conclusive evidence of...

 

[Speakpigeon]

So, do you accept that absence of evidence is evidence of absence?

Yeah, evidence towards, not conclusive evidence of...

I'm not sure how to read this. So, perhaps, you mean that you don't accept that absence of conclusive evidence is conclusive evidence of absence...

Me, I do.

And I think we all do simply because we don't have the choice, because we don't have the time to look for better evidence than absence of evidence and that we nonetheless have to go about our lives and therefore accept as conclusive evidence whatever bad evidence we have, including absence of evidence, including absence of conclusive evidence.

Obviously, a judge will try to gather good evidence before he takes it to be conclusive but all judges will dismiss any claim not supported by any evidence and therefore accept the absence of any evidence, as well as the absence of any conclusive evidence, as conclusive evidence.
EB

- - - Updated - - -

Sure, but we're not discussing whether believers are pushy, we're discussing whether absence of evidence is evidence of absence. That is an issue well beyond what believers do.

"Absence of evidence is evidence of absence" is not beyond what believers do, if you're taking from the POV that this issue wouldn't be the right proposition for believers to use.

I just mean that whether absence of evidence is evidence of absence is an issue well beyond what believers do.
EB

 

[Treedbear]

So, absence of evidence is evidence of absence; just don’t confuse such evidence as implying some kind of undeniable guarantee.

Did i miss the post where someone made that claim?

Yes, here someone did:

I still think absence of evidence is evidence of absence.

It's self contradictory

...

I wasn't saying the evidence had to be undeniably guaranteed. I'm saying that you're claiming there is in fact evidence, and that it's in the form of the lack of evidence. If you don't see how that's a logical contradiction I give up. You'll need to explain how you can deduce that there is a lack of evidence without in the process presenting some kind of supporting evidence.

 

[Wiploc]

Yes, here someone did:

I still think absence of evidence is evidence of absence.

It's self contradictory

...

I wasn't saying the evidence had to be undeniably guaranteed. I'm saying that you're claiming there is in fact evidence, and that it's in the form of the lack of evidence. If you don't see how that's a logical contradiction I give up. You'll need to explain how you can deduce that there is a lack of evidence without in the process presenting some kind of supporting evidence.

Suppose I tell you there's a dangerous lion in your bathroom.

How do you prove me wrong? You go look. You find that there is no smell of lion, no sight of lion, no sound of lion, and nothing tears you apart and eats you.

Because of the lack of evidence, you conclude that there is no lion.

That's common sense, not contradiction.