2 THE EVOLUTION OF LIFE 
than the late Sir George Stokes, a former president 
of the Royal Society, yet in his ‘ Lectures on 
Light” he says, in reference to the stars: ‘We 
can hardly suppose that life is confined to one 
particular planet circulating round one particular sun 
out of this vast multitude . . . Wecan hardly avoid 
surmising that these distant suns may, like our own 
sun, be accompanied by planets circulating around 
them, and that these planets again, or such of them as 
may be habitable, are like our own earth, tenanted 
by living beings, it may be by rational beings of 
some kind” (/oc. czt. pp. 243, 199). 
And although life has undoubtedly existed on the 
surface of our earth for an enormously long period, 
yet, as R. A. Procter pointed out,! ‘the whole 
duration of life must be regarded but as a wave 
on the vast ocean of time, while the duration of the 
life of creatures capable of reasoning upon the 
wonders which surround them is but as a ripple 
upon the surface of such a wave.” Thus, the in- 
finity of habitable worlds implies also the existence 
of an infinity of worlds not as yet habitable, or 
which have long since passed their period of 
habitability. 
If the number of suns with their attendant planets 
is so vast as to transcend all human powers of 
imagination, still more hopeless would be the 
attempt to form any conception of the infinite 
realms of space through which these orbs are dis- 
tributed. What is supposed to be the nearest 
star, situated in the constellation Centaur, is so 
1“ Our Place among Infinities,” p. 61. 
ee ae 
2 y 4 
