Furyan5

2 minutes ago, beecee said:

The reflection off the air molecules are photons/light...I see the light, I don't see air molecules.

 

 

The Sun rose for me this morning was certainly real....just as real as the same Sun was seen as setting by someone else, some where else. They were both certainly reality. Or let me put it this way, all frames of references are as valid as any other.

 

 

No, colour depends on the EMR that enters the eye.

Do you dream in color?

7 minutes ago, studiot said:

So this earlier post was incorrect then?

 

If colour is created why does it 'not exist'?

You appear to have contradicted yourself.

 

I have not contradicted myself. You can't seem to comprehend my answers.

Colors are created in the brain. They exist, in the brain. The screen does not exist in the brain. It has no color. 

2 minutes ago, studiot said:

So this earlier post was incorrect then?

 

If colour is created why does it 'not exist'?

You appear to have contradicted yourself.

 

The screen has no color. The representation of the screen which you perceive subjectively has color. What part are you not getting?

2 minutes ago, studiot said:

I didn't ask where the colour exists.

I asked what colour is the screen?

 

Please don't dodge the question.

The screen has no color.

3 minutes ago, studiot said:

So what colour is the screen at the cinema?

And please note that a cinema screen does not emit light.

It reflects light.

 

Color doesn't exist outside our brain. Our brain creates color, depending on what wavelength of light it detects. 

5 minutes ago, studiot said:

So what colour is the screen at the cinema?

And please note that a cinema screen does not emit light.

It reflects light.

 

A television screen emits. A movie theatre screen reflects. 

Just now, studiot said:

Are you saying you have never been to the cinema?

Obviously I have. A screen emits light towards my eyes and my brain creates images in response. I see those images. 

1 hour ago, studiot said:

In case you missed my post whilst you were concocting all that, I look forward to your replies to my post, sandwiched between two of yours.

My apologies, I did miss your post.

Colors are subjective visual sensations. That includes black. Black is the sensation our brain creates when our eyes detect no light from that direction. 

I'm not familiar with those devices, but I assume they have a display screen which emits light. 

1 hour ago, elias_marquez_zoho said:

Light can be a wave or a particle, depending on the experiment you make.

Wise thinkers have been debating this since Ancient times. Democritus, Aristotle, Newton, Maxwell, etc.

I don't see the relevance.

1 hour ago, beecee said:

Hmmm is that so? How about a laser beam? 

Just to add, it maybe correct that we see the Sun as it was 8.25 minutes ago, but what we see is as much reality as it is for anyone that was on the surface of the Sun. eg: If the Sun was big enough to go S/Nova, we would still be experiencing it for 8.25 minutes....just as real as our intrepid friend on the surface of the Sun, that was blown out of existence 8.25 minutes before.  

Laser beams aren't visible, unless the beam is intense enough to reflect off air molecules, in which case you're seeing a reflection of the source. Not light. 

I don't see the point of your second statement. Nobody is saying objective reality isn't real. Merely that our perceptions don't exactly match reality.

1 hour ago, John Cuthber said:

There's a whole range of electromagnetic radiation. It covers a massive range of wavelengths. The bit of the spectrum with wavelengths between about 400 and 700 mn is called visible light.

So, what Furyan5 is claiming is that something that's definitively visible, is invisible.

Many people will see that as a problem.

 

 

The description is apt. The statement is not credible.

Why are you offering it credence?

You're using circular reasoning. Claiming light is visible, because it's called visible light. Light is most definitely not visible. This doesn't match people's understanding, so obviously they will have a problem. The point is, can they back up their beliefs?

The statement is credible, I've shown the proof. 

4 hours ago, Phi for All said:

!

Moderator Note

Our rules state that you can support your statements with outside links, but you can't advertise your own stuff offsite. And members need to be able to participate without leaving the site as well. 

You're more than welcome to use parts of your "debate" in this discussion, but please don't advertise by linking to it.

 

Many people believe light (electromagnetic radiation) is visible. This includes physicists, neurologists, philosophers and even some theoretical physicist. Some of the smartest people on the planet. So if you believe you can see light, you're in good company. Understanding why you can't, is a matter of ignorance, not stupidity. That's why, "The book of general ignorance" pg122, includes the following statements. Incredibly, light is invisible. If light was in fact visible, we would be blinded by a thick fog. The book gives no reason or explanation why. This is because the explanation would require a book of it's own. The book would cover physics, neurology and philosophical arguments. Work done by numerous people over the course of centuries. Such a book does not exist, but if it did, this is the condensed version. I will be using words which some of you are not familiar with. I will put the definition in brackets. Some definitions won't make sense until you're finished, so please re-read the entire answer till it makes sense. The main reason people believe we see light is because of confusion as to the correct interpretation of words. See, has various meanings, and so does light. People often use the term, "I see what you mean.". This see is not literally seeing, but figuratively speaking. The meaning, to understand an idea. In this sense, one could "see the light.". Likewise, "I see the future.", could be construed as either having a psychic ability to foresee the future, or a visionary, able to predict future events. Then we have the conventional use of the word see, as used in, "I see a ball! ". The latter is the "see" I refer to in my argument. Light too has various definitions. We have "light and heavy", "light and dark" and light (electromagnetic radiation). The latter is nouminal (exists in the physical world) in nature, while the other two are phenomenal (exists as sensations in our brain) in nature. The distinction between phenomenal light and nouminal light will become apparent during the course of my answer. My argument specifically refers to nouminal light. Now that you are aware of the definitions of see and light which I'm referring to, let me begin. Vision has always been a contentious issue amongst the scientific community, since time immemorial. Do we perceive actual reality or representational (images created by our brain) reality. In 1781, Emmanuel Kant put forward the idea that there are two realities. An invisible, objective (existing independently of our perceptions) reality and a subjective (dependant on our perceptions), observable reality. This was the beginning of the philosophy referred to as indirect reality. Indirect reality implies that we do not see actual reality, but our brains representation of reality. The poem by Emily Dickenson only makes sense if you truly understand subjective reality. The brain is bigger than the sky For, put them side by side The one, the other will contain With ease, and you beside. What she's trying to say, is that the sky you see above you, is a image created by your brain. You don't see reality outside your head. You see a simulation and your brain is the simulator. This is no longer a philosophy. It's now fact. Confirmed by neuropsychological science. The information from the eye is sent to the brains visual cortex in a digital (piece by piece) format, not as a complete image. As some of you may know, light entering the eye, strikes a cone on the opposite side of the retina, from which the light originates. So light from our left, strikes a cone on the right. Light from above, strikes a cone on the bottom of our retina. This results in an upside down, left to right inverted image on our retina. For many years, people believed this image is what we perceived. That the brain somehow flips the image so we see the world, right side up. Then neurologists made an interesting discovery. Each cone has it's own, individual nerve leading to the visual cortex. Not only that, but a cone on the bottom of the retina is linked to a spot on the top of our visual cortex. A cone on the right of the retina is linked to a spot on the left of the visual cortex. The image isn't flipped by the brain. There is no image in the eye. The image is actually created in the visual cortex, right side up, through a mechanical process. The reality we see is not outside our heads, seen by the eyes. It's a creation of our subconscious which our conscious mind perceives. I like using the fighter jet analogy. Imagine, a squadron of fighter jets, flying in thick fog. The pilots can't see each other directly. Neither can they speak to each other directly. They need instruments to do so. Their radar tells them where they are in relation to one another. The information is displayed as dots on a screen. A dot, "represents" another plane. They communicate over radios. It's not the other pilots actual voice but a representation of the other pilots voice. It's important to note here, that the radar detects signals, but only the pilot perceives the dots. Equipment can't perceive anything. Perception is a function of consciousness. Our brain is enclosed within our skull. It has no access to the outside world except through our 5 senses. These 5 senses are our equipment as we navigate objective reality "the fog". The only difference is, we can't look out the window. We only ever see the radar screen. Luckily our screen is the best on the planet. Better than any television on the planet. The image is so realistic, we think it's real. But it has flaws. Imagine, if you will, that you're watching a beautiful sunset and it strikes you that light from the sun takes 8 minutes to reach your eyes. This means you're not seeing the actual sunset. The actual sun, set 8 minutes ago. Your beautiful sunset isn't real. There are further delays due to the speed of processing visual perceptions in the brain. What it boils down to is that our representation of reality is delayed. And the further away an object is, the more delayed the image. We see stars which might have gone super nova, millions of years ago. We see things which do not exist. So how real is our reality? To borrow a line from one of my favourite movies, "What is real? If real is what you can see, what you can touch, smell, taste and feel, then real is the interpretation of electrochemical impulses, inside our brain.". To me, reality can not be perceived. It can only be comprehended. So how does this visual process actually work? How do I see a ball? Scientists will say that we can't see the ball. We never physically make contact with the ball. All our senses rely on physical contact of some nature. Our ears detect vibrations in the air, our tongue and nostrils detect different chemicals and our eyes detect photons. We can't detect photons which don't physically strike our eyes. So we don't see the ball, we see the light. Right? Wrong! When our visual cortex creates visual representations, it creates visual representations of objects, not visual representation of light. Light coming from a ball, causes us to see, a ball. We may not see the actual nouminal ball, but neither do we see nouminal light. We see the phenomenal, representation of the ball. Even when you see a beam of light shining through the clouds, you're not seeing light. It's the dust and other particles in the atmosphere which have become visible. When you shine a torch in someone's eyes, they are seeing the element in the globe, glowing brightly. This is the sensation of brightness. It's phenomenal. Brightness is our brains interpretation of the amount of electromagnetic radiation our eyes are detecting. What you see is light "as in light and dark" and not actual light "electromagnetic radiation". We can not see nouminal phenomena. I'm running out of space, so I'll rest here and allow you to comprehend everything I've said so far. F5 Report this Argument   Pro My argument is that light is in fact the only thing we see. The mechanisms of vision are only useful because light bounces off an objective. In the same way a bat uses sonar. The bat doesn't hear stationary objects but rather the sound echoing off of a stationary object. You mentioned the sun and how it takes the lights eight minutes to reach us meaning that we are seeing an image from eight minutes in the past because we are seeing the light not the sun. The same goes for objects millions of miles away. Now I'm not going to pretend you don't have a good grasp on the processes involved or that I didn't learn anything, I didn't know for example that the bottom cone connects to the uppermost part of the visual cortex, and I'm grateful but to say that the process of human vision, no matter how it works or why, isn't a process of interpreting visible light, and only visible light I remind you, as a process of detecting the invisible that is disingenuous. Now if you're arguing the brain in a jar "how do we know anything exists at all" hypothesis I'd be happy to, but visible isn't visible like hard isn't hard is a farcical statemen and I really hoped to cover something more substantial than the need to correct the dictionary which seems to be your real goal here. One last thing, for someone who doesn't trust definitions you certainly use a lot of them in your arguments. Report this Argument

2 hours ago, swansont said:

The details of how vision works does not matter to the discussion. We could be discussing light hitting a CCD array for all that matters.

CCD arrays can't see anything as far as I'm aware. Unless you have invented a sentient array. 

1 hour ago, dimreepr said:

They're all semantic arguments; the simple fact is, a photon enters the eye and transmits its information, that makes it visible, by (any) definition. 

Not everyone agrees. That's why "The book of general ignorance" page 122, states that light is actually invisible. 

Read my full debate. Maybe you'll "see the light", metaphorically speaking of course.  advertising url removed by moderator

6 minutes ago, dimreepr said:

Sorry, I was too subtle, should have added  it's a fine line between sarcasm and a fly-by...

It's cool. It's difficult to read your facial expression on a black and white screen. 

So what do you think of my argument for light being invisible? 

22 minutes ago, dimreepr said:

Is he though?

That's how I interpreted it. How do you interpret it?

14 minutes ago, dimreepr said:

What is it you're trying to argue?

Strange is asking for proof that objective reality exists. 

12 minutes ago, Strange said:

How do you know that? What evidence would you use to convince me of that? (Bear in mind that solipsism, which your brought up before, cannot be falsified, by definition.)

Where does that 4% come from? And how is it consistent with your 1% to 99% range?

 

You're right, solipsism can't be falsified. Neither can the simulation hypothesis. All "facts" based on perceptions are based on the assumption that an objective reality exists. 

The 4% is the portion of the universe which consists of visible matter. 

The 1% to 99% is just the possible range. 

2 minutes ago, Strange said:

But surely, what we know about the Earth and its rotation on its axis is purely a mental model based on the vision (and sound and touch) experiences that our brains create? We have no way of knowing what the relationship of this brain-created models is to the outside world. Your jet pilots don't know if the dots on the screen are other aeroplanes, birds, alien space craft or just a malfunction of the hardware.

Your statements about the nature of vision seem to imply that the only conclusion we can draw is that our mental models appear to represent the Sun rising and setting due to the rotation of the Earth. We have no objective way of confirming that. Anything we do to test it results in experiences created by the brain. 

We don't even know that there is a thing called light that our eyes detect. That is just what our brains tell us is happening.

Does that mean it is something we invent? Based on what our brains tell us?

No. Reality exists. But we each perceive our own version of it, depending on our knowledge and comprehension. How close our version of reality is to actual reality is anybody's guess. We subjectively perceive only 4% of reality. But we don't know how much we don't know. Our picture could be 99% complete or 1% complete. 

4 minutes ago, Strange said:

In your view, then, is idealism agnostic on the nature of reality? In other words, it just says we can't know anything about it, beyond our mental models.

Oh no. We can draw many conclusions based on our subjective observations. Each day we see the sun rise and set, yet we can conceive the earth rotating on its axis. 

Imagine you're watching a beautiful sunset and it suddenly strikes you that the light from the sun takes 8 minutes to reach you. The sun is not where you see it. The actual sun, set 8 minutes ago. 

Objective reality is conceived while indirect reality is perceived. 

3 minutes ago, swansont said:

"Irrelevant" refers to the specific topic under discussion. You seem to want to expand this to a broader discussion, which is fine as long as you open up a new thread to do so. Not here.

The topic is "Light, visible or invisible?" 

Can you really expect to exclude vision?

2 minutes ago, swansont said:

And irrelevant to the discussion.

Depends on what you mean by "see", hence my comment about semantics.

Detecting light is what one might mean by "seeing". See above.

 

I detect light, I see a dog. Seems pretty simple to me. 

Look, I understand that for some people its difficult to alter a belief, even when faced with overwhelming evidence. For years you've been taught that visible light is visible and red light is red. What you need to understand is that physics adopts a reductionist approach. They want to keep the subjective human experience seperate from physics as it can be accurately quantified. Obviously we can't go around talking about "the light which makes objects visible subjectively", so they simplify it to "visible light". Red light should be called "The light which results in the subjective sensation of red". As you can imaging, using the full description would clog up documents with irrelevant clutter. Irrelevant to physics but not irrelevant to vision. 

22 minutes ago, Strange said:

I haven't come across the term "indirect realism" before. Is the difference between this and idealism (which says that the mental construct is all that exists) that in indirect realism, you acknowledge the external reality exists and, to some extent, matches our mental model? It sounds similar to what I have heard described as "naive realism" (the view that what we see, even though it is entirely a construct of the brain, maps pretty closely on to the external reality).

So, to take your analogy a step further, idealism would say that the dots on the radar are all that exists. The thing they represent may not exist or could just be a simulation.

Almost. Your last sentence is divided into solipsism (does not exist) and the simulation hypothesis  (could just be a simulation). 

But yes, what you call naive realism is actually indirect realism, as put forward by Emmanuel Kant in 1781. This theory has since been confirmed by neuropsychological evidence. 

9 minutes ago, Strange said:

This is why it is important to have clear and commonly understood definitions of terms (semantics) so that everyone is using the word "vision" or "see" to mean the same thing.

And the eyes do slightly more than detect light (and decode it into colours). The retina also plays a role in detecting motion, including speed and direction (which isn't surprising, from an evolutionary point of view). So I think the entire visual system has to be taken as a whole, rather than saying it is just the brain. 

(I agree completely with your main point, though, that our only conception of reality is what exists in our brain.)

 

Thank you. The difference is more than mere semantics however. It distinguishes the nature of the reality we perceive. Realism or indirect realism. 

Yes, the retina plays a part in all aspects of vision, but motion detection occurs in the brain as well. 

The bottom line is that light is noumenal in nature whereas the images we perceive are phenomenal in nature. 

Many people don't truly grasp how indirect realism works. I find the fighter jets in mist analogy helps.

Imagine a squadron of fighter jets, flying in thick mist. They can't see each other directly, so they have radar. On their radar screen, the other jets are represented as dots. This allows them to stay in formation. 

Our brain creates a similar representation in our mind and it includes a representation of us. Our entire lives we only perceive this representation. This leads many to falsely assume that what we see is actual reality. But it's not. It's a simulation of the outside world and our brain is the simulator. 

8 hours ago, swansont said:

Whether or not you can see photons has zero to do with neurology. Nothing that happens after the photon hits the eye has an impact on the answer. 

Vision occurs in the visual cortex. Not in the eye. It's a neuropsychological fact. The eyes see nothing. They merely detect light and convert them into electrochemical impulses. The process is called photo transduction and is completely unconscious. 

1 hour ago, John Cuthber said:

If reality isn't here, why are you writing to it?

You're confusing indirect realism with solipsism. 

9 minutes ago, John Cuthber said:

How do you know?
Perhaps they are all unicorns and you just have the mistaken  view that they are people?

That's the trouble with that line of "reasoning" it gets you everywhere so it gets you nowhere.

If you read properly, you'll see that a use the word "representation", implying that what we perceive is representational of actual reality. Once you truly grasp the concept you'll realize that objective reality isn't perceivable. Look like, is a term we use for subjective perception. Objective reality has no color. 

6 minutes ago, swansont said:

I think this is much more a question of semantics than it is of physics.

Wrong. It has nothing to do with physics. Vision is a neurological process. One which few truly understand. 

3 hours ago, dimreepr said:

Indeed, but it is constructed of light...

Just to be clear, I'm not suggesting the blind can't navigate or communicate; just that those that can see, use light

Yes, we need light to see objects. The point is, we don't see light itself.

3 hours ago, dimreepr said:

Other than this screen and your ability to navigate towards it...

To understand this, I'd need some dank weed... dude... 

You see the screen. Light allows you to see the screen. You don't see light, you see the screen. It's not that complicated. 

2 hours ago, StringJunky said:

Not at all. I think we are barking up different trees. 

I agree. Echo locating has nothing to do with the visibility of light. But it does allow limited shape and spacial orientation of objects. 

On 22/02/2016 at 7:24 PM, The_Believer1 said:

Hello friends!

 

I have a question about light. We all know that we see objects because they reflect light into our eyes. But we never see the actual light. So my question is why can't we see light. Or can we in fact see light. If so, how?

We can't actually see light, but to understand this, you need to understand the subjective human experience of vision. Physics tries to seperate from subjective experiences, so to physics, detection of light is seeing. Neurologically however, detecting light is merely one aspect of the visual process which results in seeing. When our eyes detect light, they send electrochemical impulses to our brains visual cortex. Here our brain creates visual representations of the objects from which the light originates. So we don't see an actual object. We see our brains representation of the object. We definitely don't see light. Light is a noumenal phenomenon. Brightness, colours and the objects we perceive are what we call phenomenal phenomenon. 

Light is not visible. We don't see light, we feel light. We see through our eyes but we detect light with our eyes. We do not detect light that passes us, only the light that enters our eyes. That's, the light that strikes our retina. Detection through physical contact is called touch, not sight. 

For us to see light, it would have to emit or reflect light. Light is colourless and moves at "the speed of light". Many people confuse light with the actual object emitting or reflecting the light. We don't see light, we see it's source. Light makes objects visible. Light itself is not visible.