ORGANIC REGULATION 99 
the external environment. An organism and its en- 
vironment are one, just as the parts and activities of 
the organism are one, in the sense that though we can 
distinguish them we cannot separate them unaltered, 
and consequently cannot understand or investigate one 
apart from the rest. It is literally true of life, and no 
mere metaphor, that the whole is in each of the parts, 
and each moment of the past in each moment of the 
present. Organic wholeness covers both space and 
time, and in the light of biological fact absolute space 
and time, and self-existent matter and energy, are but 
abstractions from, or partial aspects of, reality. 
We are thus brought face to face with a conclusion 
which to the biologist is just as significant and funda- 
mental, and just as true to the facts observed, as the 
conclusion that mass persists is to the physicist. 
We saw previously that the structure of a living 
organism has no real resemblance in its behaviour to 
that of a machine, since the parts of a machine can be 
separated without alteration of their properties. All 
of these properties are also independent of whether the 
machine is in action or at rest. In the living organism, 
on the other hand, no such separation can be made, and 
the “structure” is only the appearance given by what 
seems at first to be a constant flow of specific material, 
beginning and ending in the environment. We have 
now seen that the apparent flow has a persistence and 
power of development of~its own, which we cannot 
account for by mere constancy in the physical and 
chemical environment. What persists is not mere 
matter or energy: for the matter and energy which 
