PROGRESS 45 



multiple existence. It is for this very reason difficult 

 to fit man into many of the ordinary biological cate- 

 gories. The physical and mental structure and the 

 mode of life of even the highest of the animals are 

 for all practical purposes a fixed quantity. An ant, 

 for all its delicacy of adjustment, is little less than a 

 sentient cog shaped to fit in just one way into the 

 machinery of the community ; a dog, for all his 

 power of learning, is tied down and imprisoned within 

 a rigidity and narrowness of bodily and mental organ- 

 ization difficult for us to imagine. 



Man passes freely from one aggregation to another. 

 He can change his nation or his city ; he can belong 

 to a dozen organizations — biologically speaking, can 

 be aggregated in a dozen different ways — and play 

 a different part as unit in each. He can follow one 

 profession in the morning, another at night, and be 

 a hobby-horse rider in between. 



This plastic mind has endowed him with a new 

 biological possibility. He can do what no other 

 organism can — he can be both specialized and general- 

 ized at one and the same time. 



In biology, the aggregation of units to form units 

 of higher grade has been always followed by division 

 of labour among the units ; and this division of labour 

 has, in all infrahuman history, been made possible 

 only by an irreversible specialization.^ A soldier-ant 

 is a soldier, and there its possibilities end. It cannot 

 1 See Huxley, 'iz. 



