295 
are not proved by experiments, unless you cboose to invent 
a new definition of them, like the editor of Knowledge , or Mr. 
Spencer, to which Mr. Romanes's remark would then apply. 
And let us see one or two specimens of this self-evident 
truth, which Herschel's “ sufficiently clever man shut up by 
himself" ought to have been able to divine, if it is a real 
axiom, but not otherwise. When two equal lumps of clay 
hung close together as pendulums meet with equal velocity, 
they simply stop. All their motion appears to be lost; and 
the cleverest man in the world would have said that it is, and 
must be, until something more was known. No one could 
possibly have guessed that in those two dead, still, and cold- 
looking lumps a set of invisible vibrations would be set up, 
which we call heat, now that we have learnt by other experi- 
ments, and not by divination, what heat is ; though to be sure 
Newton did divine that, but it had yet to be proved, 
A synthetic philosopher sees somebody else turning a glass 
wheel under the friction of a piece of silk, evidently with 
more resistance than if the silk were cotton. The philosopher 
is asked to divine, without any information from experience, 
what becomes of all the force that the man has to exert 
beyond the ordinary friction. Does Mr. Spencer think he 
could have divined by any d 'priori process that a wire would 
carry that apparently lost force invisibly to the other side of 
the world, and there write sentences, illuminate a room (if the 
machine is big enough), perform chemical operations, melt 
steel, and grow peaches faster than the sun alone ? If his 
philosophy is right, he ought to be able to divine all this, and 
every natural phenomenon in the world, without a single ex- 
periment. So far from that, he does not pretend to show 
how any single transformation could have been divined d 
priori ,* or deduced from his own assumed divination of the 
persistence of force. Yet his disciples are silly enough to 
believe that he has deduced and proved them all ; which 
would indeed have “ surpassed Newton in the vastness of the 
performance." 
He thinks he gives a further proof of its axiomatic charac- 
ter by saying that Newton's “ Axioms or Laws of Motion" 
involve it, which Newton certainly did not know — nor any- 
body else. Of course they are consistent with it, because both 
are true ; but that is another thing. He forgets too that he 
denies all other “ axioms " to be axiomatic except his own. 
Then, if Newton's depend on his (which they do not the least) 3 
they cannot prove it. If they are really axioms prior to his, 
and prove it (which also they do not), then his is not the one 
Conserva- 
tion of Force 
is not an Ax- 
iom. 
