Philosophy of Light Visibility (from Light: visible or invisible?)

[Furyan5]

57 minutes ago, studiot said:

 

Yes I think every viewer (pun intended) of this thread agrees that.

 

But many viewers have told you they use a different definition of 'see' from you.

Yes, I've noticed. Many interpret detect as see. So to them, detect light and see light are the same. My infrared camera detects infrared light. By your definition, it can see. 

In my experience, theirs is overwhelmingly the most common one.

It certainly appears to be the most common one here. Is this a good or bad reflection? Time will tell.

 

That does not mean to say you are not correct about what goes on in the mind in the formation of a mental model of the image.

It's not about where images are formed, but where conscious perception occurs. 

But that is irrelevant, and until you are prepared to discuss that, no progress can be made.

Let's discuss it. If light is visible, it's the only thing that's visible. Our eyes detect nothing but light. That makes objects invisible, correct? We either see objects or we see light. 

Well I say we see representations of objects because we detect light. 

Visible light and invisible objects or visible objects and detectable, invisible Light. You decide.

 

9 minutes ago, Strange said:

I didn't say you were using it to prove god exists (that was Descartes' purpose). However, the logic is seriously flawed and cannot be used to prove you exist. (The Wikipedia page has a reasonable summary of some of the main problems with Descartes' argument: https://en.wikipedia.org/wiki/Cogito_ergo_sum#Critique)

You buy that hogwash? Before "i" was born, I never contemplated my existence. That alone satisfies me that "i" , whatever "i" is, needs to exist. For a thought to exist, a thinker is required. I'm aware of a thought, ergo, a thinker exists. 

16 minutes ago, Strange said:

I didn't say you were using it to prove god exists (that was Descartes' purpose). However, the logic is seriously flawed and cannot be used to prove you exist. (The Wikipedia page has a reasonable summary of some of the main problems with Descartes' argument: https://en.wikipedia.org/wiki/Cogito_ergo_sum#Critique)

Then I guess you haven't thought about it very much. 

I've given it more thought than you can imagine. My understanding of vision is in line with the top 5% of the population. 

 

[Phi for All]

!

Moderator Note

I split this more subjective, philosophical discussion off from the original, which is in Physics.

 

[John Cuthber]

9 hours ago, Furyan5 said:

... Light is not visible. We can't see it. ...

I don't know how to simplify that any further.

It's not a matter of making it more simple.

You need to make it less wrong.

Can you see the coast of China?

[Furyan5]

1 minute ago, John Cuthber said:

It's not a matter of making it more simple.

You need to make it less wrong.

Can you see the coast of China?

When I'm on the beach in China, I can. When I'm not, I can't. There's a difference between something being invisible and something being not visible. Is this really of any relevance? Light is invisible. Always.

[John Cuthber]

6 minutes ago, Furyan5 said:

here's a difference between something being invisible and something being not visible.

No there isn't.

One is definitively the opposite of visible- and so is the other.

You are just making up silly definitions of the words to suit your purpose.

That's more or less the sort of circular argument you wrongly accused me of.
 

The coast of China is visible if you are in the right place.

It is not, for example, visible from England.

Whether or not something is visible depends on your viewpoint (literally).

And if you are in front of a laser, you can see the light from it. If you are not in front of it then you can't so it's invisible.

 

By which pointless argument, everything ,including light, is invisible (unless you are in a position where you can see it) and you "win".

In the real world, light remains visible- just as it always was.

Edited January 26, 2018 by John Cuthber

[Strange]

7 minutes ago, Furyan5 said:

There's a difference between something being invisible and something being not visible.

See, semantics. You really need to do a much better job of defining your terms.

[Furyan5]

1 minute ago, John Cuthber said:

No there isn't.

You are just making up silly definitions of the words to suit your purpose.

That's more or less the sort of circular argument you wrongly accused me of.
 

The coast of China is visible if you are in the right place.

It is not, for example, visible from England.

Whether or not something is visible depends on your viewpoint (literally).

And if you are in front of a laser, you can see the light from it. If you are not in front of it then you can't so it's invisible.

If you ever find yourself in this position, you would be blind. But I understand your confusion. You mistake brightness for light. If you use a 40watt bulb at first you will just see brightness. If you hold your gaze steady, your eyes will adjust and you will see the element. Brightness is a subjective visual sensation resulting from overstimulation of the photo receptors. With a laser, the intensity of the light is too bright for us to see the source of the light. We see brightness, but light is not bright.

 

By which pointless argument, everything ,including light, is invisible (unless you are in a position where you can see it) and you "win".

Light is all around us during the day. 

In the real world, light remains visible- just as it always was.

This is what you believe. Many others do to. That does not make it true.

 

8 minutes ago, Strange said:

See, semantics. You really need to do a much better job of defining your terms.

Seriously? Air is invisible. My dog in the other room is not invisible. The China coast is not invisible. You people are being ridiculous. Up your game please. Drop the juvenile antics.

[Strange]

6 minutes ago, Furyan5 said:

Seriously? Air is invisible.

Earlier you were talking about "the 4%" of the universe that is visible. I assumed this meant all the stuff that isn't dark matter/energy (you didn't clarify this when I mentioned it, so I'm still not sure). But if you are going to put air, and other gases, into the invisible category, then I would guess that about 99% of the universe is not visible.

(And, of course, air can be visible under certain circumstance.)

 

[beecee]

19 hours ago, Furyan5 said:

The definition is wrong. Black is perceived. It's not a lack of perception. 

Like I said, it's a neuropsychological fact. Sadly, beyond your comprehension. 

I don't mean to insult you, I'm just stating the obvious. 

The definition is correct....Black is not a colour...Black is the absence of colour...It occurs when an object absorbs all frequencies of the visible part of the EMS.

You need to accept that.

1 hour ago, Phi for All said:

!

Moderator Note

I split this more subjective, philosophical discussion off from the original, which is in Physics.

 

Great stuff!  It certainly validates the reasonings etc, as to why scientists such as Lawrence Krauss, and Neil De Grass-Tyson are at times critical of philosophical arguments.

[studiot]

I have provided my hard physics thoughts in the original thread for comment.

 

 

[Furyan5]

3 hours ago, beecee said:

The definition is correct....Black is not a colour...Black is the absence of colour...It occurs when an object absorbs all frequencies of the visible part of the EMS.

You need to accept that.

Why should I accept a flawed belief when I know better? We don't see actual objects. We see our brains representation of them. Black is a color created by the brain. 

Great stuff!  It certainly validates the reasonings etc, as to why scientists such as Lawrence Krauss, and Neil De Grass-Tyson are at times critical of philosophical arguments.

 

 

[John Cuthber]

5 hours ago, Furyan5 said:

Seriously? Air is invisible. My dog in the other room is not invisible. The China coast is not invisible. You people are being ridiculous. Up your game please. Drop the juvenile antics.

Yep.

Air is invisible (ordinarily) from any perspective. In that regard, it's quite unusual for a physical entity.

Your dog is not visible from here and is, therefore, invisible (at least, to me).

The coast of China is also invisible (though not to the huge number of people who can see it).

And the word "invisible" is thereby   found to be one of those terms that needs some sort of clarification.

It's like a whole lot of words - for example "above" that only mean anything if you point out the viewpoint.

So a laser beam crossing the room in front of you is "invisible" from your perspective, but clearly visible from the point of view of the spider on the wall near where the beam hits.

The juvenile (i.e. uninformed or uneducated) perspective is to ignore this fact and  thus claim that- just because you can't see it- the sunbeam crossing the room is invisible.

A more grown-up view is to accept that there's nothing special about you and if someone can see it, then it's visible.

 

 

12 hours ago, Furyan5 said:

Visible is that which can be seen. Seems pretty straightforward to me.

 

[Furyan5]

4 minutes ago, John Cuthber said:

Yep.

Air is invisible (ordinarily) from any perspective. In that regard, it's quite unusual for a physical entity.

Your dog is not visible from here and is, therefore, invisible (at least, to me).

The coast of China is also invisible (though not to the huge number of people who can see it).

And the word "invisible" is thereby   found to be one of those terms that needs some sort of clarification.

It's like a whole lot of words - for example "above" that only mean anything if you point out the viewpoint.

So a laser beam crossing the room in front of you is "invisible" from your perspective, but clearly visible from the point of view of the spider on the wall near where the beam hits.

Is the light visible or is the source of the light visible?

 

 

[John Cuthber]

On 1/25/2018 at 9:51 AM, Furyan5 said:

Realism or indirect realism. 

This is a science website.

We are not likely to be cowed by someone pretending to use "big words" or technical terms (especially when you are defining what is real, but arguing that it's not semantics).

Feel free to either explain what the terms mean, or accept that you are talking nonsense.

4 minutes ago, Furyan5 said:

 

Would you like to expand on that?

 

4 minutes ago, Furyan5 said:

Is the light visible or is the source of the light visible?

Was that meant to be your post? You seem to have attributed it to me, though I never said it.

Well, it's a false dichotomy

Please try to do better

Edited January 27, 2018 by John Cuthber

[beecee]

2 hours ago, Furyan5 said:

Why should I accept a flawed belief when I know better? We don't see actual objects. We see our brains representation of them. Black is a color created by the brain. 

Firstly its not a belief....It's a scientific description based on empirical evidence, secondly your opinion that you know better, is just that....your opinion: It does not really hold much sway in a science forum, nor in science and academia in general.

Likewise black is without doubt not a colour but is what we see when there is no colour. All frequencies of the visible EMS have been absorbed by the particular object, or there are simply no photons of light present.

[Furyan5]

8 hours ago, beecee said:

Firstly its not a belief....It's a scientific description based on empirical evidence, secondly your opinion that you know better, is just that....your opinion: It does not really hold much sway in a science forum, nor in science and academia in general.

Likewise black is without doubt not a colour but is what we see when there is no colour. All frequencies of the visible EMS have been absorbed by the particular object, or there are simply no photons of light present.

Unfortunately, you've been misinformed. Now you can either cling to your current, flawed belief, or choose to know the truth. It makes no difference to me what you decide. What I do hate, is wasting my time. So choose. 

A: learn the truth about the nature of light, colors and reality, or

B: cling to your current, flawed beliefs. 

[Strange]

6 minutes ago, Furyan5 said:

or choose to know the truth

I think you have just crossed the line from "potentially interesting philosophical discussion" to "full on crackpot". You took your first steps with the misuse of "logic".

Perhaps you need to define what you mean by "truth" (a major problem in philosophy, as I'm sure you know - although less sure than I was a day ago). You seem to be using it to mean your own beliefs. 

9 minutes ago, Furyan5 said:

So choose. 

A: learn the truth about the nature of light, colors and reality, or

B: cling to your current, flawed beliefs. 

Join the Church of Furyan or suffer the consequences?

20 hours ago, Furyan5 said:

You buy that hogwash?

I don't think that dismissing the rational arguments of highly respected philosophers as "hogwash" is very helpful. And, yes, I do "buy it" because the cogito ergo sum argument seemed flawed to me when I first heard it as a child and I am pleased to find good explanations of why it is flawed.

On 26/01/2018 at 1:05 AM, Furyan5 said:

The definition is wrong. Black is perceived. It's not a lack of perception.

You are resorting to straw man arguments. He didn't say it was a "lack of perception", he said it was a "lack of colour". If you can't even argue honestly against the points other make, then there isn't much hope for this thread.

[Furyan5]

3 minutes ago, Strange said:

I think you have just crossed the line from "potentially interesting philosophical discussion" to "full on crackpot". You took your first steps with the misuse of "logic".

Perhaps you need to define what you mean by "truth" (a major problem in philosophy, as I'm sure you know - although less sure than I was a day ago). You seem to be using it to mean your own beliefs. 

Join the Church of Furyan or suffer the consequences?

There are no consequences to remaining ignorant. Some of my best friends are ignorant. 

[Strange]

45 minutes ago, Furyan5 said:

There are no consequences to remaining ignorant. Some of my best friends are ignorant. 

Not accepting something just because you (All Hail The Great & Wise Furyan) insist it is The Truth is not necessarily the same as ignorance. But as you have abandoned rational argument, I will leave you to it. 

Edited January 27, 2018 by Strange

[John Cuthber]

1 hour ago, Furyan5 said:

Unfortunately, you've been misinformed. Now you can either cling to your current, flawed belief, or choose to know the truth. It makes no difference to me what you decide. What I do hate, is wasting my time. So choose. 

A: learn the truth about the nature of light, colors and reality, or

B: cling to your current, flawed beliefs. 

Furyan, it works both ways I can also say

"Unfortunately, you've been misinformed. Now you can either cling to your current, flawed belief, or choose to know the truth. It makes no difference to me what you decide. What I do hate, is wasting my time. So choose. 

A: learn the truth about the nature of light, colors and reality, or

B: cling to your current, flawed beliefs."

 

Do you see how it works just as well whoever says it?
In order to distinguish whether it's right for me to say it or right for you to say it, we need to look at the evidence.

Now, one bit of evidence is that your position relies on "not visible" being different from "invisible".

But the dictionary tells us that they are the same.
Since you are wrong about that- which forms part of the underpinning of your ideas- your ideas are, at best, unproven.

 

Do you understand that?

 

[Furyan5]

6 minutes ago, John Cuthber said:

Furyan, it works both ways I can also say

"Unfortunately, you've been misinformed. Now you can either cling to your current, flawed belief, or choose to know the truth. It makes no difference to me what you decide. What I do hate, is wasting my time. So choose. 

A: learn the truth about the nature of light, colors and reality, or

B: cling to your current, flawed beliefs."

 

Do you see how it works just as well whoever says it?
In order to distinguish whether it's right for me to say it or right for you to say it, we need to look at the evidence.

Now, one bit of evidence is that your position relies on "not visible" being different from "invisible".

I can't see my cat. Do I have an invisible cat?

But the dictionary tells us that they are the same.
Since you are wrong about that- which forms part of the underpinning of your ideas- your ideas are, at best, unproven.

 

Do you understand that?

 

All hail the mighty dictionary, which is never wrong. 

It's ok to doubt my beliefs. But to reject them without listening to them is foolish. 

23 minutes ago, Strange said:

Not accepting something just because you (All Hail The Great & Wise Furyan) insist it is The Truth is not necessarily the same as ignorance. But as you have abandoned rational argument, I will leave you to it. 

Not listening to my arguments and still insisting I'm wrong is an interesting approach. 

[John Cuthber]

Just now, Furyan5 said:

All hail the mighty dictionary, which is never wrong. 

It's ok to doubt my beliefs. But to reject them without listening to them is foolish. 

It's not a matter of "the dictionary is king" it's a matter of the dictionary records what the words are considered to mean by the people who use them.

If you use words to mean things that differ from what the dictionary says, then people will not know what you are talking about.

If you do it knowingly- and deliberately- people with think you are trying to mislead them 

 

I listened to your beliefs- that's why I was able to show that they don't make sense.

You seem to be the one who isn't listening. If you were paying attention you would realise that, in quoting what you said, and analysing it, I have demonstrated that I do pay attention to what you write. How, if you were listening to me, did you not spot that?

[Strange]

4 minutes ago, Furyan5 said:

Not listening to my arguments and still insisting I'm wrong is an interesting approach. 

I haven't said you were wrong. You started out with an interesting, and reasonably well-argued, point about the nature of vision, the role of the brain in constructing our view of reality and so on.

But then you degenerated into name calling and just insisting you are Right, the Bringer of Truth, and that everyone who had another point of view was just wrong. So you seem to be the one who is unwilling to listen. "No you are wrong, you need the learn My Truth" is not a rational argument.

[Furyan5]

41 minutes ago, John Cuthber said:

It's not a matter of "the dictionary is king" it's a matter of the dictionary records what the words are considered to mean by the people who use them.

If you use words to mean things that differ from what the dictionary says, then people will not know what you are talking about.

If you do it knowingly- and deliberately- people with think you are trying to mislead them 

 

I listened to your beliefs- that's why I was able to show that they don't make sense.

You seem to be the one who isn't listening. If you were paying attention you would realise that, in quoting what you said, and analysing it, I have demonstrated that I do pay attention to what you write. How, if you were listening to me, did you not spot that?

I repeat. I can't see my cat. Do I have an invisible cat?

[John Cuthber]

2 minutes ago, Furyan5 said:

I repeat. I can't see my cat. Do I have an invisible cat?

Can you tell me what your cat looks like?

Also, it seem you were too busy telling me I don't listen to see this.

11 hours ago, John Cuthber said:

And the word "invisible" is thereby   found to be one of those terms that needs some sort of clarification.

It's like a whole lot of words - for example "above" that only mean anything if you point out the viewpoint.

 

Edited January 27, 2018 by John Cuthber