Existence Without Mankind: Forum Discussion

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In summary, the question of whether anything would exist if mankind wasn't around to see it is a deep philosophical and metaphysical one. While some may argue that the existence of mankind is necessary for things to exist, others believe that events and existence occur regardless of our observation. Gödel's Incompleteness Theorem adds a layer to this debate, suggesting that our understanding of the universe is limited by our own logic. Ultimately, the concept of existence and observation is complex and may never be fully understood.
  • #1
ptalar
69
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Would anything exist if mankind -- the observer/participator -- wasn't around to see

I was reading Wheelers Obituary in the Los Angeles Times. A passage in the obituary piqued my mind. What do the forumites have to say?
 
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  • #2
This is an interesting question, and one I can see both side of.

The first thing that comes to mind when I hear this though is that obviously things would happen if mankind wasn't around to see it, because obviously events had to occur in order for the Earth to develop into a place in which mankind could live on. Considering we weren't around when the Earth was molten (or even at the point of the creation of the universe), we can infer that things do occur and exist even if we aren't around, otherwise our universe itself wouldn't exist, let alone Earth.
 
  • #3
You're digging deep into philosophy and metaphysics... :wink:

My personal belief is that nature needs us (and all living creatures) to be witnesses of the existence (of everything).

Kind of evolution of that conviction back when I was a kid that the world would cease to exist each time I closed my eyes. :biggrin:
 
  • #4
Daiquiri said:
You're digging deep into philosophy and metaphysics... :wink:

My personal belief is that nature needs us (and all living creatures) to be witnesses of the existence (of everything).

Kind of evolution of that conviction back when I was a kid that the world would cease to exist each time I closed my eyes. :biggrin:

Yes. I concur this borders on metaphysics. The question which is the subject of this thread was raised by Wheeler. I had trouble deciding whether it belongs in the philosophy forum or the cosmology forum. There is a fine line since much of cosmology is theory that is yet to be proven.

I understand your premise in that without us, being all living things, there is no nature as we know it.
 
  • #5
ptalar said:
I had trouble deciding whether it belongs in the philosophy forum or the cosmology forum. There is a fine line since much of cosmology is theory that is yet to be proven.

I would say that there is a fine line between philosophy and science in general. Well, both are products of our minds and therefore are opinable.
 
  • #6
A more relevant question, perhaps, is if the laws of the universe are inherent or imposed. Does the existence of observers force the universe to behave logically, or is it a limitation the universe imposes upon us? Perhaps we are prisoners of our own logic.
 
  • #7
Chronos said:
Perhaps we are prisoners of our own logic.

That sounds like Gödel's Incompleteness Theorem extended to the whole universe... :biggrin:
 
  • #8
So we may never know the real truth.
 
  • #9
ptalar said:
So we may never know the real truth.

How about "we WILL never know the real truth?" :wink:
 
  • #10
Daiquiri said:
How about "we WILL never know the real truth?" :wink:

Yes Daiquiri, I concur, with Godel's incompleteness we will never know more than the one who created us or from whence we came, i.e: The Universe. But Godel's logic is based on basic answers to questions like True or False. Aren't we more complicated than that? I said may because we seem to be uncovering more secrets as time goes by but as to if we will hit a critical mass where we can't find out anymore and we will reach the limits of our intelligence and knowledge over time. I don't know.

I read your bio. I see your an aerospace engineer in Brescia, Italy. I am an aerospace engineer in Los Angeles, CA. I am also of Italian ancestory. Its a pleasure to talk with you on this forum.
 
  • #11
I like Daiquiri's version. Godel has a powerful argument, IMO.
 
  • #12
Did something exist before humans existed?
If not, how did we came to be as if it did?

Answer. Yes, things exist even if no one is watching (why wouldn't they?).
 
  • #13
ptalar said:
I read your bio. I see your an aerospace engineer in Brescia, Italy. I am an aerospace engineer in Los Angeles, CA. I am also of Italian ancestory. Its a pleasure to talk with you on this forum.

Sorry, I was absent from the forum for some time. The pleasure is mine, though I'm actually not italian. :smile:
 
  • #14
SF said:
Yes, things exist even if no one is watching.

Based on what evidence?
 
  • #15
Here's a poem i once read in a quantum physics book,

There once was a man who said, 'God

must think it exceedingly odd

if he finds that this tree

continues to be

when there's no one about in the quad.


Dear sir, your astonishments odd

I am always about in the quad

and that's why the tree

will continue to be

since observed by, yours faithfully, God
 
  • #16
scupydog said:
I am always about in the quad
and that's why the tree
will continue to be
since observed by,
yours faithfully, God

Since observed, but not before observed. Before observing it, we have no proof of it's existence. After we have observed it we create our logical models (which need to be proved, and that's where Godel jumps in and spoils everything) which can tell us whether it will exist after we cease our observation.

Now you could say that we can demonstrate it's existence from an indirect observation, i.e. by observing the effects of it's interactions with the ambient. In the dark, for example, we can sense it's perfume, or we can hear the noise of it's leafs waving in the wind.
Well, that's not a proof. You have once again constructed a logical model which correlates the effect to the cause, but any model can be confuted.

Note that all the world as we know it is a model created by our organism and our mind from the very moment a photon hits our retin or a soundwave bounces off our tympanic membrane.

And, by the way, in my view maybe the tree is not the right subject to argue upon, since it is a biological organism made of cells which can sense (and therefore can observe, in a way) the surrounding ambient and react to external inputs.
In other words, maybe a tree is an observer - just like us... :wink:
 
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  • #17
Daiquiri said:
Since observed, but not before observed. Before observing it, we have no proof of it's existence.

But surely that is no proof that it didn't exist before we observed it
 
  • #18
Imagine yourself in a completely dark room (no photons),
a visible light source in the room flashes on/off once.
The photons leave the light source and after a certain amount of time they hit, say an apple. Then some of them reflect off the apple and hit our retina, we have observed the apple. But the apple must have been there before we observed it because the photons were reflected BEFORE they entered our retina.
 
  • #19
scupydog said:
But surely that is no proof that it didn't exist before we observed it
And is there a proof that it did exist before we observed it?

Please note that I've never said that things don't exist if we are not watching them. What I've said is that we have no proof of their existence if we are not able to observe them.

Your affirmation quoted above is demonstrating the same thing, but from other way round.
 
  • #20
scupydog said:
Imagine yourself in a completely dark room (no photons),
a visible light source in the room flashes on/off once.
The photons leave the light source and after a certain amount of time they hit, say an apple. Then some of them reflect off the apple and hit our retina, we have observed the apple. But the apple must have been there before we observed it because the photons were reflected BEFORE they entered our retina.

The flaw in your demonstration lies in the fact that you are putting yourself in a privileged position, where you know what happened before that photon hit observer's retina.

The observer doesn't know what happened, he only has the information carried by that photon. Based on that single information he has to use his physical models to explain how and why did that photon hit his retina.
And not necessarily his conclusion needs to be that there is an apple in the room.

A physical model cannot be taken as a proof of the existence of that apple. The answers it gives are valid only within the limits of validity of the model itself.
 
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  • #21
Daiquiri said:
The observer doesn't know what happened, he only has the information carried by that photon.

The information that is carried by the photon BEFORE he observes it, is still carried by the photon whether he observes it or not. The information that the apple exists is carried by the photon on its journey to the retina, and as journeys take time the apple must exist before it is observed.
 
  • #22
scupydog said:
The information that is carried by the photon BEFORE he observes it, is still carried by the photon whether he observes it or not. The information that the apple exists is carried by the photon on its journey to the retina, and as journeys take time the apple must exist before it is observed.

You have stuck to that argument and don't want to admit (or recognise) that it is flawed. I invite you to re-read our whole discussion and sleep on it a little bit.

And while sleeping, try to think about this: what is that makes an apple what it is (i.e. an apple)?
 
  • #23
Daiquiri said:
You have stuck to that argument and don't want to admit (or recognise) that it is flawed. I invite you to re-read our whole discussion and sleep on it a little bit.

And while sleeping, try to think about this: what is that makes an apple what it is (i.e. an apple)?


The information that is carried by the photon BEFORE he observes it, is still carried by the photon whether he observes it or not. The information that the apple exists is carried by the photon on its journey to the retina, and as journeys take time the apple must exist before it is observed.

Do you disagree with my above post, if so please tell me why.
 
  • #24
scupydog said:
The information that is carried by the photon BEFORE he observes it, is still carried by the photon whether he observes it or not. The information that the apple exists is carried by the photon on its journey to the retina, and as journeys take time the apple must exist before it is observed.

Do you disagree with my above post, if so please tell me why.

I disagree, almost completely.
1) A concept of the "information" is (IMHO) meaningful only in presence of an intelligent observer which can give a significance to it, which can encode the "input" (or "signal") to the "information".
2) In this particular case we have an observer, so there is a potential information for him. But that information cannot be used by the observer to definitely prove the existence of the apple. He can only make conjectures about the provenience of the photon and it's possible meaning, and only within the limits of the logical (or interpretative) models he uses.
 
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  • #25
Daiquiri said:
I disagree, almost completely.
1) A concept of the "information" is (IMHO) meaningful only in presence of an intelligent observer which can give a significance to it, which can encode the "input" (or "signal") to the "information".
2) In this particular case we have an observer, so there is a potential information for him. But that information cannot be used by the observer to definitely prove the existence of the apple. He can only make conjectures about the provenience of the photon and it's possible meaning, and only within the limits of the logical (or interpretative) models he uses.
Your first point is fair as a stand alone comment (that is to say, I agree with it).

But, surely for the photon to be carrying any such information in the first place (irregardless of whether or not an observer can make sense of that information) this implies (at least in my mind) the existence of the apple a finite time before observation (once again, this does not have to be an observation that yields meaningful conclusions*). How else would information about the apple be encoded in the photon?

That is to say; the fact that the photon is carrying information at the time of observation does not assume knowledge of what happened prior to observation, but the observation of such information implies the existence of the apple (or simply 'encoding body') prior to observation.

* Unless you are implying that the apple does not exist unless we understand it to (i.e. by deriving the 'correct' conclusion from our observation and application of physical principles).
 
  • #26
White Ink said:
Your first point is fair as a stand alone comment (that is to say, I agree with it).

But, surely for the photon to be carrying any such information in the first place (irregardless of whether or not an observer can make sense of that information) this implies (at least in my mind) the existence of the apple a finite time before observation (once again, this does not have to be an observation that yields meaningful conclusions*). How else would information about the apple be encoded in the photon?

That is to say; the fact that the photon is carrying information at the time of observation does not assume knowledge of what happened prior to observation, but the observation of such information implies the existence of the apple (or simply 'encoding body') prior to observation.

* Unless you are implying that the apple does not exist unless we understand it to (i.e. by deriving the 'correct' conclusion from our observation and application of physical principles).


Thank you white ink for putting across my point more clearly.
 
  • #27
White Ink said:
...
surely for the photon to be carrying any such information in the first place (irregardless of whether or not an observer can make sense of that information) this implies (at least in my mind) the existence of the apple a finite time before observation (once again, this does not have to be an observation that yields meaningful conclusions*).

You have just performed a following thought experiment:
- You have assumed the existence of the apple, and the photon hitting it.
- That allowed you to imply that the information about the existence of the apple is carried by the photon.

So now you have:

1) If there is an existing sentient observer which receives that photon, he could become aware of the existence of the apple. Although not necessarily, because his physical model applied to that photon could demonstrate the existence of something else, and therefore the information about the existence of the apple could be lost forever.

2) If there is no observer to receive that photon, nothing can be said about the existence of the photon itself, and therefore neither about the existence of the apple. The apple might exist but there is nobody to demonstrate it.

The situation n.2 is possible because of YOUR sentient existence, which has allowed you to perform this thought experiment.

White Ink said:
...
That is to say; the fact that the photon is carrying information at the time of observation does not assume knowledge of what happened prior to observation, but the observation of such information implies the existence of the apple (or simply 'encoding body') prior to observation.

If there is no observer the information carried by the photon (and the existence of the apple) cannot be demonstrated and remains only a thought experiment.

White Ink said:
* Unless you are implying that the apple does not exist unless we understand it to (i.e. by deriving the 'correct' conclusion from our observation and application of physical principles).
And finaly, that is what I meant. :smile:
 
  • #28
I hate to quote myself, but I realize that maybe you guys have lost the final point of my reasoning, so I have to do it:

Daiquiri said:
Please note that I've never said that things don't exist if we are not watching them. What I've said is that we have no proof of their existence if we are not able to observe them.
 
  • #29
Daiquiri said:
White Ink said:
* Unless you are implying that the apple does not exist unless we understand it to (i.e. by deriving the 'correct' conclusion from our observation and application of physical principles).

And finaly, that is what I meant. :smile:

Daiquiri said:
Please note that I've never said that things don't exist if we are not watching them. What I've said is that we have no proof of their existence if we are not able to observe them.

The two statements you seem to be backing here represent a contradiction in your logic in my view. Just because one observer does not have proof of something existing, this does not mean that that something does not exist (see next paragraph).

In essence, if you agree with the point I made after the asterisk, you are essentially arguing that if an observer intercepts information about the apple (from the photon) and then misinterprets that information, the apple ceases to exist. By this logic, the existence of things is entirely dependent on the physical models used to describe them (not to mention that the apple would have to cease being once the misinterpretation was made; it's existence prior to then is implied (not assumed) because the photon has had the information encoded into it a finite time before observation).

This logic is something which to me represents an infinite digression since physical models are created in order to explain what we have observed in the natural world. By your reasoning, initially having no physical model (for example, just like at the beginning of time) implies that nothing would be able to exist because there was a time in the universe's history in which we had no physical models to account for observations which could have been made. Yet, we (at least perceive ourselves to) exist after such a time when there were no working physical models at our disposal.

I agree with you in some respects, but something spontaneously beginning/ceasing to exist as a result of observations and more essentially their interpretations, is quite alien to me.
 
  • #30
SF said:
Yes, things exist even if no one is watching.
Daiquiri said:
Based on what evidence?

One day I was looking at a tree. It was standing tall. I left the area and came back a few days later. I noticed the same tree had fallen down. I guess I should of assumed that things magically go "poof!" when I'm not around.
 
  • #31
White Ink said:
The two statements you seem to be backing here represent a contradiction in your logic in my view.

You are right. I have not read your statement after the asterisk in the correct way and so the phrase "And finaly, that is what I meant" is not correct. The interpretation by which the things "do not exist unless we understand it to" doesn't rappresent my thoughts and it should be quite clear by now. I was eager to end my long reply and the result is a mistake due to misreading your final phrase. I have no problems to admit my mistake.

I was, and am, desperately trying to talk about proofs of existence.
You could have arrived quite easily to my point by reading everything else that I wrote before that stupid phrase. Did you do it? Do you have something to say about my arguments?

There's an entire page of my thoughts on the issue up there.

So let me repeat one more time my point:
"What I've said is that we have no proof of their existence if we are not able to observe them."

White Ink said:
something spontaneously beginning/ceasing to exist as a result of observations and more essentially their interpretations, is quite alien to me.
Tell me, is this seriously all that you have understood of all the things I've said?
 
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  • #32
LightbulbSun said:
One day I was looking at a tree. It was standing tall. I left the area and came back a few days later. I noticed the same tree had fallen down. I guess I should of assumed that things magically go "poof!" when I'm not around.

I have to admit that I don't get what you mean... Can you elaborate on this one?
 
  • #33
Daiquiri said:
Tell me, is this seriously all that you have understood of all the things I've said?

No. That was just something I wrote based on your agreement with the comment after the asterisk (something which we have now cleared up). Unfortunately I don't have time to write a longer reply right now, I'm in a bit of a rush.
 
  • #34
Daiquiri said:
So let me repeat one more time my point:
"What I've said is that we have no proof of their existence if we are not able to observe them."



The Quantum entanglement of photons
 
  • #35
scupydog said:
The Quantum entanglement of photons
Scupydog, if you don't elaborate on that phrase a little bit more, how can I get what's up on your mind? o:)
 
<h2>1. What is the purpose of discussing existence without mankind?</h2><p>The purpose of discussing existence without mankind is to explore the idea of a world without human beings and to consider the potential consequences and implications of such a scenario.</p><h2>2. Is this discussion purely theoretical or is there evidence to support the idea of existence without mankind?</h2><p>This discussion is primarily theoretical, as there is currently no concrete evidence to suggest that human beings will suddenly disappear from the world. However, there are various scientific theories and studies that can inform our understanding of how the world might function without mankind.</p><h2>3. How would the absence of mankind impact the environment and other species?</h2><p>The absence of mankind would likely have a significant impact on the environment and other species. Without human activity, the natural world would be able to thrive and evolve without interference. However, the sudden disappearance of humans could also lead to imbalances in certain ecosystems and the extinction of certain species that have become dependent on human presence.</p><h2>4. What potential scenarios could lead to existence without mankind?</h2><p>There are various potential scenarios that could lead to existence without mankind, such as a catastrophic event that wipes out the human population, a gradual decline in human population due to factors like disease or environmental disasters, or the development of advanced technology that replaces the need for human labor and ultimately renders us obsolete.</p><h2>5. How can discussing existence without mankind benefit our understanding of the world?</h2><p>Discussing existence without mankind can benefit our understanding of the world by allowing us to think critically about our impact on the planet and the interconnectedness of all living beings. It can also help us to consider alternative ways of living and the potential consequences of our actions as a species.</p>

1. What is the purpose of discussing existence without mankind?

The purpose of discussing existence without mankind is to explore the idea of a world without human beings and to consider the potential consequences and implications of such a scenario.

2. Is this discussion purely theoretical or is there evidence to support the idea of existence without mankind?

This discussion is primarily theoretical, as there is currently no concrete evidence to suggest that human beings will suddenly disappear from the world. However, there are various scientific theories and studies that can inform our understanding of how the world might function without mankind.

3. How would the absence of mankind impact the environment and other species?

The absence of mankind would likely have a significant impact on the environment and other species. Without human activity, the natural world would be able to thrive and evolve without interference. However, the sudden disappearance of humans could also lead to imbalances in certain ecosystems and the extinction of certain species that have become dependent on human presence.

4. What potential scenarios could lead to existence without mankind?

There are various potential scenarios that could lead to existence without mankind, such as a catastrophic event that wipes out the human population, a gradual decline in human population due to factors like disease or environmental disasters, or the development of advanced technology that replaces the need for human labor and ultimately renders us obsolete.

5. How can discussing existence without mankind benefit our understanding of the world?

Discussing existence without mankind can benefit our understanding of the world by allowing us to think critically about our impact on the planet and the interconnectedness of all living beings. It can also help us to consider alternative ways of living and the potential consequences of our actions as a species.

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