CONSCIOUSNESS, 21 
sible how, to a mass of molecules of nitrogen, oxygen, 
hydrogen, carbon, phosphorus, and so on, it can be 
otherwise than indifferent how they lie or move; here, 
therefore, is the other limit to the knowledge of natural 
science. Even the mind imagined by Laplace cannot go 
beyond this, to say nothing of our own. Whether the 
two limits to natural science are not, perchance, identical, 
it is, moreover, impossible to determine.” 
In these last words the possibility is indicated that 
consciousness may be an attribute of matter, or may 
appertain to the nature of the atoms. And we may 
add, that the attempt has of late been repeatedly made 
to generalize the sensory process, and to demonstrate 
it to be the universal characteristic of matter, as by 
von Zéllner, in his work on the Nature of Comets, 
which has created such a justifiable sensation. He 
holds that, if by means of delicately-formed organs 
of sensation it were possible to observe the molecular 
motions in a crystal mechanically injured in any part, 
it could not be unconditionally denied that the motions, 
hereby excited, take place absolutely without any simul- 
taneous excitement of sensation. We must either re- 
nounce the possibility of comprehending the pheno- 
menon of sensation in the organism, or “hypothetically 
add to the universal attributes of nature, one which 
would cause the simplest and most elementary opera- 
tions of nature to be combined, in the same ratio, with 
a process of sensation.” 
It might be imagined that reflections of this kind 
would lead to the delusive abysses of speculation; but 
if, still speaking only of organisms, we descend from 
the manifestations elicited by sensations of desire and 
