358 NATURE AND MAN. 



powers of sensation and movement ; let him take the cue into his 

 hands and himself strike the ball ; let him hold his hand on the 

 table so that the rolling ball shall strike it and make him feel its im- 

 pact ; let him hold the second ball and feel the shock imparted to 

 it by the stroke of the first. Can any one deny that he would thus 

 acquire a dynamical conception linking together the whole succes- 

 sion of phenomena, which he was previously quite incapable of form- 

 ing ; that this dynamical conception is quite as directly based upon 

 the experience derived through his " force-sense," as his kinetic 

 expression was upon that derived through his visual sense ; and that 

 this cognition of the force producing the motions is, therefore, 

 fully as much entitled to be introduced into a logical doctrine 

 of causation, as the visual cognition of the motions themselves ? 

 If it be replied that we have no proof that the movement of the 

 ball we strike is produced by the force which we consciously exert 

 in striking it, I simply reply that we have as much proof of it as 

 we have of anything which rests upon universal experience, and 

 which we can verify experimentally as often as we choose to try — 

 quite as much as we have of the existence of anything whatever 

 that is external to ourselves. 



Let us take, again, the simple case of magnetic attraction. A 

 man who knows nothing of magnetism sees a piece of iron 

 brought within a certain distance of what looks like a horse-shoe 

 bar of the same metal, suddenly jump towards its approximated 

 ends; and might, as before, correctly express the fact in "terms 

 of motion." But let him take the piece of iron in his hands, so 

 as to feel the "pull" upon it when brought sufficiently near the 

 magnet, and he then becomes conscious, through his force-sense, 

 of a power of which he was before utterly ignorant. 



Thus, as it seems to me, an analysis of those psychical experi- 

 ences, on which all our cognitions of the physical universe around 

 us are really based, irresistibly lands us in the conclusion that, as 

 Herbert Spencer expresses it, " All the sensations through which 

 " the external world is known to us, are explicable by us only as 

 "resulting from certain forms of force;" the direct derivation of 

 our conception of force from cur own experience of muscular 

 tension (or as I should myself say, from our own sense of effort) 

 being "a fact which no metaphysical quibbling can set aside." 



