Prof. Ernst Haeckel. 35 



substance, or spirit, or ghost, or spook ; still less is con- 

 sciousness such an entity. The latter as a correlate is sui 

 generis. But if it must be compared to anything, let it be 

 not to any gas or material substance, however impalpable, 

 but to the imponderable agencies or forces — electricity, heat, 

 light, etc. The life of man is a process resembling electric 

 phenomena more than a rarefied gas, but it is distinctly cor- 

 related with certain physical conditions, and neither a gas, 

 ether, nor electricity, nor anything but itself ; and we must 

 get rid of such gross materialism in dealing with the subject 

 as that involved in the conception that life is a substantial 

 entity. A state of consciousness is not a property or qual- 

 ity, or even a process of matter, but a sui generis correlate 

 of such processes, and in no sense one of them or like them 

 else it could not be their correlate.* 



We must also thoroughly recover from the crude idea 

 that correlates are mechanical mixtures, or we shall be ma- 

 terialists or spiritualists and not understand monism. The 

 law is, that no correlate ever resembles its antecedent cor- 

 relates, but is entirely distinct from them. For instance, 

 water is the result of the chemical combinat'on of ox3'gen 

 and hydrogen gases, but is entirely different from them, and 

 so it is with every other chemical, vital, or mental j)rocess 

 and product. 



In regard to vital and social phenomena, they are in a 

 still higher degree disparate and entirely different from, 

 and wholly incomparable with, the materials and changes 

 from which they result. There is no " music " in the ^ilayer 

 or the piano, nor in the vibration of the air caused by the 

 playing ; but the correlate of that vibration, as it affects our 

 nervous system, is the state of consciousness which we call 

 music ; and it resembles nothing whatever which has pro- 

 duced it, not even the changes in the nerve-cells imme- 

 diately preceding or attending the consciousness. The pas- 

 sage from the pliysiological change to its psychical cor- 

 relate, as Prof. Tyndall says in his Belfast address, is " un- 

 thinkable,*' but yet, as he says, it is a correlate ; it " has its 

 correlative in the physics of the brain " — and that is the all- 

 important fact.f AH correlations are in the same sense 



* " My final conclusion, then, about the substantial soul is that it explains noth- 

 ing and fjuarantees notliing. Its successive thoughts are the only intelligible and 

 verifiable things about it, and definitely to ascertain the correlations of these 

 with brain-processes is as much as psvchology can empirically do." (Principles 

 of Psycholofi.v, Chap. X, by Prof. William James, of Harvard University.) 



+ See his Fragrnients of Science, fifth edition (,Appleton"s), pp. -119, 4aO, 463, 524, 

 and to the end of the volume. 



