Because it was just quoted by SUNRAY in post #219
Light switches wired wrongly
- Thread starter 81011
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As I've said, all this discussion about two fingers, and the choice between them, and which direction they move, is just unnecessary complication. The test is so simple (and, theoretically, almost 'foolproof'
) in that, no matter what one does, absolutely nothing changes if one closes one's non-dominant eye but things DO change if one closes the dominant one. Is that not the case for you?Ah, so he did
Whilst it is true that I gave a very different description of the test back then, as I have just been saying, it transpires that it really doesn't matter a jot how one does it - since it is always the case that closing one's non-dominant eye changes nothing, whereas closing ones dominant eye does result in changes.
Quite honestly, if I understood your results I'd have an understanding.As I've said, all this discussion about two fingers, and the choice between them, and which direction they move, is just unnecessary complication. The test is so simple (and, theoretically, almost 'foolproof'
Do me a favour and let me know what happens when you try this:
Close your left eye and align your finger with the distant object and observe what happens when you alternate your eyes.
My finger jumps to the right.
Then.
Close your right eye and align your finger with the distant object and observe what happens when you alternate your eyes.
My finger jumps to the left.
"The obvious" happens, just as you describe for yourself - but that proves nothing about dominance, since you haven't included the situation in which both eyes are operating, Having on looked at each eye separately.
I think it's now your turn to do me a favour, and undertake a variant of your experiment, as follows...
Close your left eye and align your finger with the distant object and observe what happens when you open your left eye
For me, absolutely nothing 'happens' (my right eye is dominant)
Then.
Close your right eye and align your finger with the distant object and observe what happens when you open your right eye
My finger jumps (and becomes two fingers if I focus on the distant object).
Do you get different results from me?
This is not how the test is usually done, but it again illustrates the fact that closing one's non-dominant eye changes nothing, but that closing one's dominant one does - and the reason for that is obvious from 'the Laws of Physics' (well, really basic geometry!).
All the way through the thread you have been discussing closing eyes and seeing thing move around
I see the additional finger to the right
I see the additional finger on the left
Blatantly yes, just like all the way through this thread.
However what you are telling me is:
1. In your test with both eyes open you see one finger
2. In your test with both eyes open you see two fingers
Is it only me who sees a difference there?
Is only one statement true?
Closing one eye and seeing if things move as compared with having both eyes open. You compared having one eye open with having the other eye open - that tells you nothing about dominance (other than that you do have a dominant eye - a few people don't, in which case closing eyes would make no difference)
As I've been saying, forget about how many fingers you see. The only relevant question (seemingly regardless of anything else) is whether, starting with both eyes open, anything changes when you close one eye. You should find that things change when you close one eye, but that nothing changes when you close the other one.
The only thing that has ever happened when I do this is one of the fingers (or distant objects) disappears.
So which of you statements is incorrect?
The 'second finger' you're seeing will obviously disappear when you close one eye (either eye).
The one which doesn't disappear should remain unchanged relative to 'the background' when you close your non-dominant eye, but should move relative to the background when you close your dominant one.
You really only need to 'draw a few triangles' to understand why all this works as it does - the point being that if one has a dominant eye, the triangle will be right-angled, whereas if there were not a dominant eye it would be isosceles. In other words, the dominant eye looks 'straight ahead' at an object, whereas the non-dominant eye rotates a little towards the dominant one in order to see object being viewed
As I keep saying, I have no interest in how many fingers are seen.
In fact, prior to this discussion, I hadn't really come across people talking about 'two fingers', and nor can I recall having previously come across people who could not easily tell whether closing one eye did or did not alter the perceived relationship between closer and more distant objects.
Right lets get down to basics.
When I, and for that matter the vast majority of others, focus at a point with both eyes - other positions will be out of focus and mostly a double image, most noticeable with a significant distance difference - ie 2 fingers Vs several metres or more between 2 parts.
When I close one eye; one of the double images ie one finger will disappear, much of the non focussed point will come towards being better focussed to some degree.
Swapping the open eye; most of the non focussed point will move within the field of vision - due to the triangles you mention.
Nothing I can do will selectively cancel one of the images with both eyes open, however I can concentrate on one or the other.
Nothing I can do can do, and as far as I can make out the vast majority of others too, can make the image with both eyes open stay the same when I close one as the double image has to disappear, the laws of physics dictate that to be so.
If this means that I, and the vast majority of others, don't have a dominant eye then so be it but as a result of your test seeming to indicate I do not have a dominant eye I can not imagine the problems you describe.
As far as I'm concerned- having 2 working eyes which are receiving 2 images, I don't understand how one cannot see the double image effect and the resulting lack of change when the non working eye is closed.
yes, to some extent, particularly if some of the positions are close to the eyes and others aren't.
that seems to vary between people and, as you say, is most likely to happen when there is a substantial distance difference, and particularly if one of the objects is fairly close to the eyes.
Indeed - if/when one does see a double image, those images will be coming from different eyes, so one will inevitably disappear when you close one eye.
there is a tendency for that to happen, I imagine because there is a (probably 'subconscious') 'readjustment of the focus' in the eye which has remained open.
So far, everything you say remains as I would expect. However, if it were your non-dominant eye that has been closed, other than (a) the (inevitable) loss of any second image you were seeing with two eyes, and (b) possibly the focussing readjustment just mentioned, nothing else should happen. In particular, nothing which is still visible should move sideways relative to anything else. Is that not what you are seeing?
However, if it were your dominant eye that you closed then, in addition to (a) and (b), there should be a very obvious (quite marked) sideways movement of the still-visible finger relative to things in the 'background'. Again, is that not what you are seeing?
That's obviously what one would expect. If you are seeing double images, neither will disappear until you close one of your eyes.
As above, YES, disappearance of the double image is inevitable when you close one eye (and maybe some change in focussing) BUT, other than that, nothing should change - in particular the still-visible finger should not move sideways relative to the background.
If you didn't have a dominant eye (a few people don't), it would be a little more complicated, since you would then get sideways movement of the still-visible finger relative to background when you closed either eye (think 'triangles' again - we now have an isosceles one!), the movement being in opposite directions when closing one or other eye.
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Yes that is what I am seeing; one image disappears and the other stays where it is, let's call it image A
Absolutely not; one image disappears and the other stays where it is, let's call it image B - Just as I'd expect it to
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What a load of rubbish, The mere fact that you make the statement negates much of what you have been describing, the finger may appear to jump sideways - In reality Image A visible in one eye will disappear when that eye is closed and image B visible in the other eye will appear.
This takes it straight back to the non focussed point appearing to show as double image with both eyes open. A situation which you admit to seeing, except you keep denying it.
So which is it; do you see the non focussed point as a double image or not?
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A further point, not quite connected to the above, if you look at for instance, a piece of square timber, around 25mm square, with both eyes open, and 'square on', you should be able to see the face, and simultaneously, the two side. The closer your eyes to the timber, the more of the side faces you can see.
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