LAW OF CAUSATION. 379 



ditional sequences, there will result a much greater number of 

 conditional ones. Certain causes being given, that is, certain 

 antecedents which are unconditionally followed by certain 

 consequents ; the mere coexistence of these causes will give 

 rise to an unlimited number of additional uniformities. If 

 two causes exist together, the effects of both will exist toge- 

 ther; and if many causes coexist, these causes (by what we 

 shall term hereafter the intermixture of their laws) will give 

 rise to new effects, accompanying or succeeding one another in 

 some particular order, which order will be invariable while 

 the causes continue to coexist, but no longer. The motion of 

 the earth in a given orbit round the sun, is a series of 

 changes which follow one another as antecedents and conse- 

 quents, and will continue to do so while the sun's attraction, 

 and the force with which the earth tends to advance in a 

 direct line through space, continue to coexist in the same 

 quantities as at present. But vary either of these causes, 

 and this particular succession of motions would cease to take 

 place. The series of the earth's motions, therefore, though 

 a case of sequence invariable within the limits of human 

 experience, is not a case of causation. It is not uncon- 

 ditional. 



This distinction between the relations of succession which 

 so far as we know are unconditional, and those relations, 

 whether of succession or of coexistence, which, like the earth's 

 motions, or the succession of day and night, depend on the 

 existence or on the coexistence of other antecedent facts 

 corresponds to the great division which Dr. Whewell and 

 other writers have made of the field of science, into the in- 

 vestigation of what they term the Laws of Phenomena, and 

 the investigation of causes ; a phraseology, as I conceive, not 

 philosophically sustainable, inasmuch as the ascertainment of 

 causes, such causes as the human faculties can ascertain, 

 namely, causes which are themselves phenomena, is, therefore, 

 merely the ascertainment of other and more universal Laws of 

 Phenomena. And let me here observe, that Dr. Whewell, 

 and in some degree even Sir John Herschel, seem to have 

 misunderstood the meaning of those writers who, like 



