Page:The Works of H G Wells Volume 11.pdf/229

 the class of negative terms. The negative term is in plain fact just nothing; "Not-A" is the absence of any trace of the quality that constitutes A, it is the rest of everything for ever. But there seems to be a real bias in the mind towards regarding "Not-A" as a thing mysteriously in the nature of A, as though "Not-A" and A were species of the same genus. When one speaks of Not-Pink one is apt to think of green things and yellow things and to ignore anger or abstract nouns or the sound of thunder. And logicians, following the normal bias of the mind, do actually present A and Not-A in this sort of diagram:—

ignoring altogether the difficult case of the space in which these words are printed. Obviously the diagram that comes nearer experienced fact is:—

with no outer boundary. But the logician finds it necessary for his processes to present that outer Not-A as bounded, and to speak of the total area of A and Not-A as the Universe of Discourse; and the metaphysician and the common-sense thinker alike