242 ESSAYS OF A BIOLOGIST 



full properties of a molecular compound such as 

 water, for instance, cannot be deduced at present 

 from what we know about the properties of its con- 

 stituent atoms of hydrogen and oxygen. The prop- 

 erties of the human mind cannot be deduced from 

 our present knowledge of the minds of animals. 

 New combinations and properties thus arise in time. 

 Bergson miscalls such evolution "creative." We had 

 better, with Lloyd Morgan, call it "emergent." 



With mind, we fmd a gradual evolution from a 

 state in which it is impossible to distinguish mental 

 response from physiological reaction, up to the in- 

 tensity and complexity of our own emotions and in- 

 tellect. Since all material developments in evolu- 

 tion can be traced back step by step and shown to be 

 specializations of one or more of the primitive prop- 

 erties of living matter, it is not only an economy of 

 hypothesis, but also, in the absence of any evidence 

 to the contrary, the proper conclusion, that mental 

 properties also are to be traced back to the simplest 

 and most original forms of life. What exact signifi- 

 cance is to be attached to the term "mental proper- 

 ties" in such organisms, it is hard to say; we mean, 

 however, that something of the same general nature 

 as mind in ourselves is inherent in all life, something 

 standing in the same relation to living matter in 

 general as do our minds to the particular living mat- 

 ter of our brains. 



But there can be no reasonable doubt that living 



