Sorry, i'm a little new at this posting thing so please bear with me.
Anyway, the point of the argument is not that object is red, if you felt like it it could be a white poka dotted bow tie. The real point is that is NOT something that every man can see as red. The entire concept is that everyone sees the same object differently.
Example, two villages on opposites sides of a mountain see a comet. The village on the right see the comet as a sign of inpending doom and destruction. The other village however, sees it as a sign that a good harvest will come. The problem being, that when both villages try and tell their story to the other, the single comet is made out to be mulitipule and conflicting omens, thefore causeing confusion and anger between the two villages.