Talk:Emission theory (vision)

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"50 percent of American college students"? I know we're not the smartest lot, but I think most of us understand that our eyes do not illuminate the objects we look at. This whole article seems a bit fishy, but I don't know enough to edit. Anyone up to it? Xyzzyva 15:56, May 18, 2005 (UTC)

• I couldn't find any reference for this assertion other than sites that mirror Wikipedia. Anyone else have any information on it? Edwardian 22:25, 25 September 2005 (UTC)

• I found something that appears to me to cast some suspicion on those findings[1], but I'm afraid it's beyond my area of expertise to figure it out. Edwardian 06:33, 4 December 2005 (UTC)

I'm going to have a go. There's already another page that refers to Newtonian emission theory, but calls it "emitter theory" - this phrasing is pretty obscure, it only throws up about 300 hits on Google as opposed to about 7,500 for the more usual spelling. And it refers to it as a wave theory based on Maxwell's equations that only became disprovable in the 1960s' (as opposed to the 1910's).

so I think I'll have to rewrite the emitter page (or turn it into a redirect for "emission theory"), and then extend the existing "emission theory" page. Maybe rename the "eye-ray" stuff (which doesn't seem to provide any supporting links or references) to emission theory (vision) or similar, and crosslink.

It might even be worth starting a list page of "emission theories" (Newton and Ritz for starters). ErkDemon 8 July 2005 22:38 (UTC)

[edit] Original argument?

To convince such students of the error of assuming that light needs to be emitted from an optical device (such as the eye) to accomplish perception, once could say that it would be impossible for a camera to capture an image because the lens of a camera does not emit any light.

This isn't an obvious contradiction; it's perfectly consistent to assume that any image-forming object would emit rays, or that all objects emit rays and a camera simply records its perceptions of nearby objects. I removed the argument. -- Beland 16:19, 25 September 2007 (UTC)

[edit] Mind-bogglingly stupid

Errrm... I just know there's going to be a good answer to this, but if we were to see by light emitted from our eyes, why can't we see just as well in the dark? William M. Connolley (talk) 22:57, 30 January 2008 (UTC)

According to Plato (Timaeus 45b–e) the light in our eyes is too weak to penetrate the darkness on its own and needs external light. In this respect the extramission theory always presupposes the external light. → Aethralis 09:36, 21 April 2008 (UTC)