I am reading the book "A History Of Optics" by Oliver Darrigol, and I came across this sentence (under the heading Visual Fire): Isn't this a low-quality argument? This can be directly disproved by the fact that humans inbabilty to see in dark, viz. if humans can see things from the "fire" emitted from their eyes, then they can see things in dark. Is this just a bogus argument given push because of its fancy look or was there any strong support for this view? The question took significance for me, as every concieved principles will be trying to look for generality, and this principle is also concieved to look for generality in explaining things; and I was wondering whether the proper support for this argument has anything to donate for the future development of the nature's explanation.