Page:Chesterton - Eugenics and Other Evils (Cassell, 1922).djvu/55

 knife, at a small table where we sit. The whole of civil law rests on the supposition that we are witnesses; that we saw it; and if we do not know about it, who does? Now suppose all the witnesses fall into a quarrel about degrees of eyesight. Suppose one says he had brought his reading-glasses instead of his usual glasses; and therefore did not see the man fall across the table and cover it with blood. Suppose another says he could not be certain it was blood, because a slight colour-blindness was hereditary in his family. Suppose a third says he cannot swear to the uplifted knife, because his oculist tells him he is astigmatic, and vertical lines do not affect him as do horizontal lines. Suppose another says that dots have often danced before his eyes in very fantastic combinations, many of which were very like one gentleman cutting another gentleman's throat at dinner. All these things refer to real experiences. There is such a thing as myopia; there is such a thing as colour-blindness; there is such a thing as astigmatism; there is such a thing as shifting shapes swimming before the eyes. But what should we think of a whole dinner party that could give nothing except these highly scientific explanations when found in company with a corpse? I imagine there are only two things we could think: either that they were all drunk, or they were all murderers.

And yet there is an exception. If there were one man at table who was admittedly blind, should we not give him the benefit of the doubt? Should we not