It is easy to see from what special type of knowing the copy-theory arose.  In our dealings with natural phenomena the great point is to be able to foretell.  Foretelling, according to such a writer as Spencer, is the whole meaning of intelligence.  When Spencer’s ’law of intelligence’ says that inner and outer relations must ‘correspond,’ it means that the distribution of terms in our inner time-scheme and space-scheme must be an exact copy of the distribution in real time and space of the real terms.  In strict theory the mental terms themselves need not answer to the real terms in the sense of severally copying them, symbolic mental terms being enough, if only the real dates and places be copied.  But in our ordinary life the mental terms are images and the real ones are sensations, and the images so often copy the sensations, that we easily take copying of terms as well as of relations to be the natural significance of knowing.  Meanwhile much, even of this common descriptive truth, is couched in verbal symbols.  If our symbols fit the world, in the sense of determining our expectations rightly, they may even be the better for not copying its terms.

It seems obvious that the pragmatic account of all this routine of phenomenal knowledge is accurate.  Truth here is a relation, not of our ideas to non-human realities, but of conceptual parts of our experience to sensational parts.  Those thoughts are true which guide us to beneficial interaction with sensible particulars as they occur, whether they copy these in advance or not.

From the frequency of copying in the knowledge of phenomenal fact, copying has been supposed to be the essence of truth in matters rational also.  Geometry and logic, it has been supposed, must copy archetypal thoughts in the Creator.  But in these abstract spheres there is no need of assuming archetypes.  The mind is free to carve so many figures out of space, to make so many numerical collections, to frame so many classes and series, and it can analyze and compare so endlessly, that the very superabundance of the resulting ideas makes us doubt the ‘objective’ pre-existence of their models.  It would be plainly wrong to suppose a God whose thought consecrated rectangular but not polar co-ordinates, or Jevons’s notation but not Boole’s.  Yet if, on the other hand, we assume God to have thought in advance of every possible flight of human fancy in these directions, his mind becomes too much like a Hindoo idol with three heads, eight arms and six breasts, too much made up of superfoetation and redundancy for us to wish to copy it, and the whole notion of copying tends to evaporate from these sciences.  Their objects can be better interpreted as being created step by step by men, as fast as they successively conceive them.