246 
in no place— that is, as I have said, nowhere! I do not 
remember ever seeing such a strange contradiction of ideas 
solemnly stated as philosophy as we find in this part of the 
letter. For example, he says, “Doubtless the centres offeree 
vary in their distance one from another, but that which is 
truly the matter of one atom touches the matter ot its 
neighbours;” and yet he says that, according to Ins assump- 
tion “matter and the atoms of matter would be mutually 
penetrable.” The impenetrability of matter s.mply means 
that two parts of it cannot be in one and the same place at the 
same time. According to this theory of Mr. Faraday, no. 
only two particles of this matter, but any number of them, can 
be in one and the same place at the same time, and that 
though they vary in their “distances” one from the other! 
We think that nothing can be more certain than that, it the 
least particle of matter can be in the same place with another 
particle, and hence any number of particles occupy that same 
place also at that same time, the masses which the accumula- 
tion of these particles form must be just as mutually penetrable 
as their minutest parts. The mere multiplication of that 
which needs no space for its presence can never call for space, 
and hence the infinitely absurd conclusion that the earth ltse 
needs no space in which to revolve! But what does this 
really mean ? It simply means, when analyzed, that extension 
is not a mode of existence in material substances . opace anc 
extension are identical in true thinking, unless you regard 
space as a mere possibility of extended existence. This is the 
true notion of the idea in the abstract ; and, if substance does 
not need space, it has not extension ! Here we fall back on 
our idea of knowledge as a legitimate inference from the reve- 
lations of consciousness, and ask whether it is such an inference 
that material substances have no size ? Is it a mistake to 
imagine that certain objects are really long or short, or deep 
or high ? It will certainly require very powerful chemical 
experiments to convince us that mankind are mistaken m 
believing in extension as a mode of material existence. 
What are the experiments of this most eminent among 
electricians ? He says, “ as regards the mutual penetrability 
of the atoms, one would think that the facts respecting 
potassium and its compounds, already described, would 
enough to prove that point to a mind which accepts a fact foi 
a fact, and is not obstructed in its judgments by Preconceived 
notions.” But what is the fact? Merely that 8,328 atoms 
will go into a space which seems full with 430 . It would be 
about as powerful reasoning to argue that because a carpe - 
bag, which one person says is crammed, will take m tmee 
