600 DISCUSSION ON THE 
to break a deadly uniformity. Of course, we can escape from the 
difficulties caused by infinite time if we accept the opinion entertained by 
some philosophers that time is not real. With them we may hold that 
the notion of time is due to the nature of our perception. If we accept 
such an idea, we can assert that consciousness in its passage through the 
space-time continuum meets but does not cause events. It then follows, 
however, that all our fancied activities are an illusion. Against any such 
belief we must put what surely is our constant and invariable experience. 
We have a measure of freedom of will. Labour and struggle are real. We 
can get nearer truth and overcome evil as we strive for goodness. Thus 
I am forced to conclude that the time-process must be real. Yet, unless 
time is an illusion, or unless alternatively the cosmos had a beginning 
in time, any picture of the evolution of the universe must fail to 
satisfy. 
Let us take it, however, that the primal mist that filled all space in 
the beginning aggregated into masses of roughly equal size in a finite 
universe and that these masses slowly began to condense and revolve. 
Whence came their rotation? To this question I can find no satisfying 
answer. Let us ignore the difficulty. Out of condensation and rotation 
came the spiral nebulae, the universes of thousands of millions of stars 
with which space is strewn. Obviously, with relatively few exceptions, 
the great nebulae are built to a common pattern. They are results of 
rotation, and the picture of vast rotating lenticular masses throwing off 
stars, like drops at the edge of a fly-wheel, satisfies the imagination. But 
why are the arms of the spirals so short ? We should expect arms which 
curl repeatedly round the central nucleus. None such exist; and yet 
there is apparently no ejection into space of early-born stars to account 
for the disappearance of the coils of stars that ought to be visible. 
The different chains of reasoning by which Jeans has been led to assign 
a period of millions of millions of years for the age of our universe seem 
to me to demand respect. I doubt whether they are conclusive. But I 
wish that there were certain knowledge of the development and decay of 
typical stars. Theories abound. Some are magnificent in the ingenuity 
and in the intellectual power which have gone to their making. But the 
final theory of stellar evolution has not emerged. I confess, moreover, 
that I am by no means happy with regard to the expanding universe ; 
and I doubt whether Doppler’s principle is rightly applied to measure the 
velocities of recession of the great nebulae. It is not improbable that the 
reddening of their light is due to other causes. If the great nebulae are 
moving away as fast as is suggested, we are lucky to be living at an epoch 
when we are able with our telescopes to see them at all. Moreover, the 
Friedman-Lemaitre equations give contraction as an equally possible 
alternative to expansion. May it not be that a velocity of approach is 
masked by some other effect ? A universe that was continuously con- 
tracting would have a snug end. Steady and continued inflation, either 
of a currency or of a universe, is disquieting. 
It is, however, when we come to the formation of planetary systems 
that I feel especially uneasy. The current theory is, as I have said, that 
the earth and its associated planets arose from the encounter of our sun 
with a wanderer which came so near as to disrupt it some few thousand 
ee a ee ae a 
