THE PRESIDENTIAL ADDRESS. 9 
secondary qualities such as colour and the like, which the older science 
in its mechanistic scheme ignored, but which are specially associated 
with life and consciousness. Apparently the quantum does not fall com- 
pletely within the causal deterministic scheme: the same is true of life. 
Life is not an entity, physical or other. It is a type of organisation ; it is 
a specific principle of central or self organisation. If that organisation is 
interfered with we are left, not with bits of life, but with death. The 
nature of living things is determined, not by the nature of their parts, but 
by the nature or principle of their organisation. In short, the quantum 
and life seem to have this in common, that they both behave as wholes. 
I have before now endeavoured to explore the concept of life in the 
light of the more general concept of the whole. A whole is not a sum of 
parts, or constituted by its parts. Its nature lies in its constitution more 
than in its parts. The part in the whole is no longer the same as the part 
in isolation. The interesting point is that while this concept of the whole 
applies to life, it is according to the recent physics no less applicable to 
the ultimate physical units. Thus the electron within an atom is no 
longer a distinct electron. There may be separate electrons, but when 
they cease to be separate they also cease to be. The eight electrons 
which circulate in an oxygen atom are merged in a whole in such a way 
that they have lost their separate identity ; and this loss of individuality 
has to be taken into account in calculations as to the physical behaviour 
of the atom. The physicist, in fact, finds himself unable to look upon 
the entity which is one eighth of eight electrons as the same thing as a 
single electron. At the very foundation, therefore, of physics, the 
principle or category of the whole applies no less than in the advanced 
structure of life, although not in the same degree. In the ultimate 
_ analysis of the world, both at the physical and the biological level, the 
_ part or unit element somehow becomes shadowy and incoherent, and the 
very basis of mechanism is undermined. It would almost seem as if the 
world in its very essence is holistic, and as if the notion of individual 
parts is a practical makeshift without final validity in the nature of 
_ things. 
The general trend of the recent advances in physics has thus been 
towards the recognition of the fundamental organic character of the 
material world. Physics and biology are beginning to look not so utterly 
unlike each other. Hitherto the great gulf in nature has lain between the 
material and the vital, between inorganic matter and life. This gulf is now 
in process of being bridged. The new physics, in dissolving the material 
