If i can see him, can he see me?

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Discussion Overview

The discussion revolves around the visibility of a person in a dark field when illuminated by a flashlight. Participants explore the conditions under which one person can see another, considering factors such as light reflection, distance, and the human eye's ability to perceive light.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants suggest that if a person can see the light from a flashlight, it implies that the flashlight holder should also be able to see them, as photons reflect off their body.
  • Others argue that while the flashlight holder may see some light reflecting off the person, it may not be sufficient to recognize them due to the lower intensity of light reflected compared to the light from the flashlight.
  • One participant notes that the ability to see someone also depends on the intensity of the flashlight and the distance between the two individuals.
  • There is a mention of the human eye's limitations in detecting low amounts of light, suggesting that distance plays a critical role in visibility.
  • Another participant emphasizes the complexity of the situation, stating that various factors, including environmental conditions, can affect visibility.

Areas of Agreement / Disagreement

Participants generally agree that distance and light intensity are important factors in determining visibility, but there is no consensus on the exact conditions under which one person can see another in this scenario. Multiple competing views remain regarding the implications of light reflection and recognition.

Contextual Notes

Limitations include assumptions about the intensity of the flashlight, the distance involved, and the environmental context, which are not fully explored or quantified in the discussion.

1MileCrash
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Imagine you are in a dark field. A man with a flashlight is looking for you. you sse the light from his flashlight.

doesn't this mean he should be able to see you? after all, photons are reflecting off of you if his light reaches your eyes.

Or is it simply that his eyes have adjusted to the brightneas of the objects he is directly shining his light on?

sorry for any typos, on my phone and the text doesn't show, om typing blindly here.
 
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I think there is no reason he shouldn't be able to see you.
Yes , you won't be able to see him as the photons reflecting from his body aren't sufficient enough to make an image in ur eye.
 
He might see you, but may not recognize you because you are not giving off as much light. To say that you see his flashlight or light from his flashlight does not mean that you see all of the light from his flashlight. To say that he sees you does not mean that he sees all of the light reflecting from you. Yes he should see some of the light reflecting from you, but it may not be enough to distinguish you from the rest of the environment.
 
Fun Value said:
He might see you, but may not recognize you because you are not giving off as much light. To say that you see his flashlight or light from his flashlight does not mean that you see all of the light from his flashlight. To say that he sees you does not mean that he sees all of the light reflecting from you. Yes he should see some of the light reflecting from you, but it may not be enough to distinguish you from the rest of the environment.
That depends on the intensity of flashlight and distance from the source.
 
1MileCrash said:
Imagine you are in a dark field. A man with a flashlight is looking for you. you sse the light from his flashlight.

doesn't this mean he should be able to see you? after all, photons are reflecting off of you if his light reaches your eyes.

Or is it simply that his eyes have adjusted to the brightneas of the objects he is directly shining his light on?

sorry for any typos, on my phone and the text doesn't show, om typing blindly here.

There's a bit of mixing concepts here. It is true that, unless you are a perfect black body absorber, which you are not, you WILL reflect many of the photons that strike you. However the human eye is not able to detect light of sufficiently low amount. If you are 10 feet from the man then there is a good chance that he will be able to see you as long as he has a decent flashlight. But if I'm about 150 yards away, I can see his flashlight, but he might not be able to see me since much less light hits me and reflects back.

Then we get into if the eye and brain can actually distinguish you from your surroundings. There are way too many variables to really go in depth, but on the few occasions I've had to go look for something in the woods in the dark, I can tell you that it is NOT easy! If you are simply standing in an open field then I would say that as long as the man isn't too far away, he should be able to see you. If you were in the brush behind the plants, it would be much more difficult.
 

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