GENERAL BIOLOGY 



nature is ultimately dependent upon some sort of 

 molecular organization of which we are profoundly 

 ignorant. But we are almost equally ignorant of 

 the nature of the organization of the simplest 

 chemical compounds. We know nothing, for in- 

 stance, of the relation existing between the oxygen 

 and the hydrogen that gives water its peculiar 

 properties. These properties are inherent, and were 

 they to alter fundamentally, our whole body of 

 chemical theory would be upset. On the other 

 hand, the manner in which these properties are 

 revealed to us is determined primarily by external 

 (environmental) conditions, i.e. those of tempera- 

 ture and pressure. We think of H 2 O as a liquid 

 because that is the form that our usual conditions 

 of temperature and pressure cause it to assume. 

 But the liquid state is, of course, no more charac- 

 teristic of the compound than the gaseous or solid 

 state. If we should keep a quantity of water at a 

 temperature of C. for a hundred years, we should 

 have no reason for supposing that its liquid nature 

 would be altered in the slightest if the temperature 

 were finally raised ten degrees. Indeed, we may say 

 that it is the specific characteristic of water to be a 

 solid, a liquid, or a gas, at definite calculable levels 

 of temperature. 



In the same way, the adjustment of internal 

 relations to external ones is a specific characteristic 

 of the organism. To put it another way, the solid 

 condition of ice is not " caused " or " produced " 

 by the lowering of the temperature, except in a 



