ON FURTHER INVESTIGATION 
 
Indulge me one last effort to reach you with my viewpoint and my pics.
Here are four pictures to follow step by step. Are you up for this? In the first picture #1 there are the railroad tracks and the man. I have now added a house in the distance behind the man.
 
What you need to ask yourself is:
Is the picture properly drawn? 
That is, is the perspective correct?
That is, are the man, house and railroad tracks depicted in generally correct proportions in terms of perspective -- e.g., if the man walks back to the house will he fit through the door, based on the apparent size of both the man and of the hut-house?
Is the picture, in other words, essentially free of any distortion, illusions or anomalies, as is intended?
No need to answer. The matter can be proven with the simple rules of perspective lines being shown -- as in the next picture 1A. This shows geometric proof that the man is depicted the proper height to fit in the door of the hut house.
 
If he was that size in a real photo, then the hut's door would be that size in any photo having no greater distortion than the human eye has.
Now let's go to pic# 2. Here we have the man and the hut again, but the man is placed further up the tracks.
 
Note that the man is standing directly across  from the hut and that the hut's shadow is landing on the man's foot to emphasize his location.
Note that the man's height compared to the width of the RR tracks is far greater  than would be found in any reality.
Note that the man is much taller than than hut or its door.
Note that if this was a photo, you'd say the man was a giant of unique height, wouldn't you? Can you say that same thing even though it's a drawing (correctly made), and say that the man LOOKS (appears, apparently is, seems) like a giant man (or else the hut is a toy  hut and the RR tracks a miniature  track)?
As you are no doubt now expecting, the next drawing #3 shows both men in the picture with the hut.
 
Since the drawing can be shown to be correctly drawn according to the rules of perspective, and that I have correctly drawn a grossly giant man way bigger than a house, if you still honestly cannot say the upper man looks clearly like a huge giant, and that the lower man is smaller  and normally sized (as a photo of such a scene would also show him), then:
Should I think you cannot, as most people can, properly interpret perspective drawings, nor presumably even photos, which are also in correct perspective?
I cannot believe that.
So what is going on? Why doggedly belittle with such fixated vigour the correct notion that distance cues hugely and greatly and even primarily affect  apparent sizes [of the moon or men or whatever] -- such that you cannot even see the evidence anymore and grudgingly insist it's merely somewhat "plausible" [maybe I should feel grateful I got an admission that far advanced from your earlier view that it was "simply ridiculous" and a thing you "cannot accept"]? But tho' plausible, you say it's still a wanting "speculation," forever requiring "further research" -- and you're offering NO OTHER things that are "primary" if this concept is not.
What  research should be done??? You say the moon illusion is stronger than any paper illusion. But your "I-see-only-a-bit-of-an-illusion" perception is one that you arrogate as being a fact  that doesn't match up to the real horizon moon's hugeness, and so therefore, "more research must....etc."
Perhaps your perception being off is all we'd need to research?
Once more (and a pic is not required to "visualize" this): If some persons walking away from you DON'T look like they're getting apparently smaller as they get more distant, then those persons will look like they're growing astonishingly bigger, No?
If they get from 5 or 10 feet away to a half-block away and still have gotten no "smaller" then how "marginally" bigger do you  think would they look? How many obvious examples do you need? Well, I'll give you a couple more.
Clearly if you actually did see the illusions in the latest drawings , that you now claim you can barely see, "if I see them at all," or see "just a "bit" as you say, then you'd have to wholly admit my case.
E.g., The vertical wall illusion shows a moon stuck on a further-away part of the wall, a moon that one can clearly see is the FULL HEIGHT of the wall. The closer moon is less than HALF that height. That is what you call just a "bit" of an illusion? (Yes. But only in your #1 "ruler" mindset.)
So, here, appended & amended, the pic is shown again below -- with 3 moons this time.
Now, if that moon-on-the-wall pic gave any visual indication that ANYof the moons were the same size, then it would look like the first pic next below:
  
Now click on this image below:
 
Now go back and forth and look at the two pics above to see that there is no illusion in the first upper pic, but that in the second lower pic, the illusion is that the middle moon is VERY much larger-looking than the closest moon, and this is obviously not just "marginally" so, right? Or do you still say no?
Is this still  marginal to you?
What I see now is: Only the 1st and 3rd moons appear to be the same apparent size, but seen at different distances -- that is, as it is moved further away, the same moon (or person) gets smaller on the retina, but has not actually shrunk smaller.
However, the middle moon ("like a big pizza pie") is looking like it is actually bigger -- not interpreted by the eye as the same size as the first moon [as I thus interpret it in the drawing with the red lines] -- because in this lower picture it does not  get smaller when it is placed "further away" on the wall.
The drawings contain nothing other than distance clues (as defined in DaVinci's notebooks, including the two that you, Michael DaFinley, cavalierly dismiss by saying they "don't count").
Now that you already admit they're distance cues, and admit that converging lines pose no special non-distance alternative, and that there are no other aspects there to point to as "primary" causes of the illusion [except when you are reaching every so often for some other mysterious Far-Fetched Fuzzy Fluky theorem probably turning the "real" illusion off or on, or the like] then it comes down to this, in my opinion:
If you still say "marginal," then you seem to have actually trained yourself to have a "huge" immunity to seeing these illusions.
Or am I the one having greater illusions?  (But as an experienced artist I am well trained not to, and can also consciously check my work with defined geometric perspective rules as a check-and-balance to illusion.)
If you're still seeing & saying marginal, then you "not even 'hardly' seeing  the illusion" has now become the only remaining way for you (consciously or not) to continue to disparage my concept (not really mine, as it is believed widely, probably universally in the "optical illusion racket" except for "apparently" you).   Even earlier pics in which you admitted you saw the illusion, you are hedging that they ALL were "just barely noticeable" or "marginal" and such like.
If you still say so, then you are now an actual honest example of "believing is seeing" -- because you now have a conflict of interest -- in your commitment at all costs to deny the concept [that the *primary* operating factor in size perception is due to distance cues -- even  to causing the eye to perceive larger comparitive angular sizes when they are really equal (E.g., the "hugeness" of the man higher in the picture in the illustrations, OR the hugeness of the moon on the horizon or on the wall)].
This is why I earlier "disqualified" you as an impartial observer. For this debate to bear any fruit for you and accurately understanding this, from now on, all the pics -- with only written questions (no additional verbal instructions) must be placed before several other impartial people -- outside family (like people at a meeting) -- and then let's honour their readings of the pics -- instructing them only: "No rulers -- "Use your eyes only and describe which thing(s) just simply look or appear  bigger or smaller to you."
Bob
P.s. Yes, I agree that the vastness of the night sky to make the moon look smaller could have greater power to do that than my further drawings of the Ponzo effect have.

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