xin.] ORGANIC SUBORDINATION. 149 



its existence to the advance of optics ; and yet the subject- 

 matters of optics and histology have no connexion what- 

 ever. But such a connexion is merely accidental and 

 instrumental : the connexion of the sciences in the series 

 ■which I have drawn above, on the contrary, is logical and 

 real, and is based on the dependence of the things 

 themselves. 



So far, as the reader will perhaps have perceived, I have Obligation 

 taken these ideas about the dependence of the properties of ° °™ '^' 

 things, the one on the other, from Comte's Positive Philo- 

 sophy. ^ What follows, though I claim no originality for 

 its substance, has not, so far as I am aware, been stated in 

 a systematic form before. 



We have seen that in inorganic nature, and up to the Depend- 

 laws of life, there is a relation of dependence of the laws ™^°| j^^^ 

 of one science on those of another, which dependence is one on the 

 not reciprocal. The same relation is continued between 

 the different laws of life : animal or motor life depends on Veseta- 

 vegetative or nutritive life; and mental life depends on ^^j^^j^^^j^ 

 animal life. And among these also, the dependence is not and mental 



• * lif6 



reciprocal : vegetative life may exist without animal life, 

 and animal life may exist without mental life. Mental 

 life depends on animal life, and animal life depends on 

 vegetative life, just as vegetative life depends on chemical 

 properties, and chemical properties depend on those of heat 

 and electricity. These are facts of observation. Through- 

 out the whole vegetable kingdom we see vegetative life 

 without animal life ; and throughout a great part of the 

 animal kingdom, we see very energetic animal life with 

 scarcely a trace of mental life. But the converse is im- 

 possible ; there is not, nor under the laws of life can there 

 be, any such thing as animal life without vegetative or 

 nutritive life for its basis ; or mental life, without animal 

 life as its basis. It is a consequence of this relation, that 



1 See Harriet Martineau's condensed translation of Comte's Positive 

 Philosopliy, vol. i. chap. ii. 1 have read Comte only in the above-men- 

 tioned translation, which I believe is thoroughly trustworthy. The series 

 I have drawn in the text difters from Comte's in detail, but is the same 

 in principle. 



