CORRESPONDENCE, 1856-G6. 317 



million of cubic miles, though we can conceive it, as proved by 1863. 

 our knowing truth and falsehood about it. 



I am, yours very truly, 



A. DE MORGAN. 



To Eev. Dr. Whewell. 



April 3, 1863. 



MY DEAE SIE, Did I provoke you to an ontological discus- 

 sion ? Did I chalk my hat and say, ' Now I'd like to see the 

 man who says that this is not silver lace' ? That's what I call 

 provoking a discussion. I asked you, who are Kantescient, 

 whether you knew of a certain speculation in the later editions 

 of Kant ; and you say No. I am pretty sure you would have 

 remembered it at once if it had been there. 



I am quite sure we shall never solve the problem which my 

 analogy went to suggest. But for all that, if we only envisage 

 a quality acting through space as memory acts through time, we 

 put multipresence upon a definite basis of unintelligibility 

 there, I have managed to spell the word, and that is something 

 gained. 



I value the analogies of space and time the two indis- 

 missible extensions ; and I have before now made much profit of 

 the very remark you quote. 



For aught I know, a body may act where it is not ; it may 

 leave consequences behind it. An annihilated star, which is seen 

 by light emitted during its existence, may be said, for aught we 

 can tell, to act where it is not, in as true a sense as matter, in 

 attracting distant matter, can be said to act where it is not. 



But presence is a very ill-used notion. If a particle really do 

 attract all others, it is present throughout the universe. It is 

 present in one quality in others, for aught we know. The 

 presence of matter is the presence of all its qualities the only 

 things we know. Now who is to say that the spheres of the 

 qualities have the same diameters or even the same centres ? 



Grant one centre to qualities of a particle, and there may be 

 millions of centres, all effective in spheres of different radii. 

 The sphere of attraction may be the biggest, or it may not. 



Mansel, I detect partly by private, partly by public evidence, 

 is in the state of the old logicians about infinity. He cannot 

 separate the mathematical notion from the old mixture of infinite 

 in quality and in everything. Leibnitz had it to a considerable 

 extent, in spite of his power over the mathematical notion. 



