THE FORCE BEHIND NATURE. 363 



atmosphere, whose recombination gives forth heat and light And 

 if we look still further back for the source of the sun's radiant 

 energy, we should find it, perhaps, in the progressive consolidation 

 of the primeval " fire-mist " — nebular matter. 



But whence nebular matter? And whence the force which 

 draws its particles together, and which manifests itself as light 

 and heat during their consolidation ? Here we come to a wall, 

 to the other side of which we seem at present to have no access. 



But is there no other side ? Does not the whole course of the 

 preceding inquiry show the unsatisfaction (if I may revive an 

 obsolete word) of resting in any inherent "potency" of matter 

 as the ultima ratio of the existing kosmos ? If we think the man 

 foolish who supposes the main shaft of a cotton mill to turn oj 

 itself, merely because he sees it apparently end in a wall which 

 conceals from him the source of its motive power, are we not 

 really chargeable with the like folly if we attribute sell-motion to 

 the ultimate molecules of matter, merely because the power that 

 moves them is hid from our sight? The mere physicist may see 

 no possible way further. But there is a philosophy which has 

 fully as true and as broad a basis in man's psychical experience, 

 as can be claimed for the fabric of physical science ; and in the 

 admirable words of the great master I have already quoted (Sir 

 John Herschell, in his Familiar Lectures on Scientific Subjects, 

 p. 460), I shall sum up an argument which this paper is intended 

 rather to illustrate and enforce by an appeal to the familiar facts 

 of consciousness, than to present in strict logical form : — 



*' In the mental sense of effort, clear to the apprehension of 

 '* every one who has ever performed a voluntary act, which is pre- 

 "sent at the instant when the determination to do a thing is 

 "carried out into the act of doing it, we have a consciousness of 

 " immediate and personal causation which cannot be disputed or 

 "ignored. And when we see the same kind of act performed by 

 " another, we never hesitate in assuming for him that conscious- 

 "ness which we recognize in ourselves ; and in this case we can 

 "verify our conclusion by oral communication." "In the only 

 "case in which we are admitted into any personal knowledge of 

 " the origin of force, we find it connected (possibly by intermediate 

 "Unks untraceable by our faculties, yet indisputably cotmected) 



