INTRODUCTION. 37 



monious, although in themselves different. "When in scientific inquiry we have 

 traced a multitude of complex phenomena up to a single force, and have shown 

 that their variety is due only to the diversity of the conditions under which that 

 force is operating, we still have to ascertain the source of this force ; and it is 

 no sufficient account of it to show that it is but a metamorphosed form of 

 some other force. We may even be led by Science to look upon all the phe- 

 nomena of the Universe as the results of the operation of a single dynamical 

 agent, varied in the modes of its manifestation according to the nature of the 

 mechanism (so to speak) which it puts in action. The existence of this force, 

 causa causarum, still remains unaccounted for; but at this point Physical 

 Science ends, and the question becomes one of an entirely different order. 

 The inquiring mind cannot stop here; and if it seek a solution in its own ex- 

 perience, it is led by the consciousness that by its own volition it can give 

 rise to a force which is capable of operating upon the material world, to look to 

 an Intelligent Will as the ultimate spring of all those changes for which it 

 can find no other source, and to regard the Forces of the Universe in general 

 as so many modes of operation of the one Omnipotent and Omnipresent Mind. 

 Viewed under this aspect, therefore, all the phenomena of Nature which have 

 not their origin in the mental power of subordinate beings, must be considered 

 as the immediate exponents of the Will of the Creator ; and thus again we are 

 led to regard their so-called "Laws," as but Man's expression of the condi- 

 tions under which the Divine Power appears continually operative in producing 

 them. 



In a purely Scientific Treatise, however, it is in the scientific sense alone that 

 the terms " Cause" and "Law" are to be understood; and wherever they occur 

 in the following work, therefore, the Author would imply by the former the 

 exercise of a force or power, Physical or Vital, operating under certain definite 

 material conditions ; whilst by the latter he would designate every such general 

 exponent of those conditions under which a force operates, as may enable the 

 results to be determined beforehand. Thus the Law of Gravitation defines in 

 general terms that constant relation between the bulk and the distance of masses 

 of matter, on the one hand, and the amount of force which is developed by their 

 mutual attraction, on the other, which enables us, by an acquaintance with the 

 particulars of the former, to predicate those of the latter. And the Law of 

 Definite Proportions expresses in general terms that relation between the "com- 

 bining equivalents" of different substances, which enables us, when we apply it 

 to particulars, to determine precisely how much of a compound substance will 

 be decomposed by the force of Chemical attraction, which a given amount of 



