602 DISCUSSION ON THE 
of the existence of planetary systems. I suspect that such systems are 
much more numerous than is at present believed. 
I need scarcely emphasise that the issue raised by the relative 
frequency of planetary systems is of great philosophical importance. 
From Juda, through the Christian Church, has come a belief in ethical 
theism which has been a strong and ennobling influence in European 
civilisation. To-day such belief rests upon the conviction that we can 
only explain the universe by assuming that it is due to creative thought 
and will, associated with purpose and plan. Such purpose appears most 
clearly on earth in the progressive development of mind, which has ended 
in the recognition of moral values by humanity ; and the religious outlook 
of many of us is determined by our belief that God has thus created man 
for His service. But, if consciousness should be proved to be but a rare 
accident of a vast, otherwise aimless, universe, such belief in God would 
be encumbered by a new perplexity. I may add that the belief would not 
disappear, since we should still have to explain why man has been created 
with the conviction that he must be loyal to goodness and truth. 
Such philosophico-religious speculation is, however, premature. We 
need more facts and, that we may obtain them, we need new instruments 
of greater power and precision. The interferometer, we may hope, points 
the way to instrumental triumphs in the future. If only an instrument 
could be invented which should enable us to determine whether stars, 
within, say, a hundred light-years’ distance, have planetary systems 
attached to them! We should then know whether any of the few thousand 
stars near the sun have planets on which life may conceivably exist. If 
even one such system were found, the present theory of planetary origins 
would collapse. Failing any such invention of a super-telescope, there 
remains the possibility of wireless communication. As I have already 
indicated, I have no doubt that there are many other inhabited worlds, 
and that on some of them beings exist who are immeasurably beyond our 
mental level. We should be rash to deny that they can use radiation so 
penetrating as to convey messages to the earth. Probably such messages 
now come. When they are first made intelligible a new era in the history 
of humanity will begin. At the beginning of the era the opposition 
between those who welcome the new knowledge and those who deem it 
dangerously subversive will doubtless lead to a world-war. But the 
survivors, when they extricate themselves from the economic conse- 
quences of the peace treaty, will begin what we may correctly term a 
strenuous correspondence course. I should like to be living then. We 
might get a true understanding of the evolution of the universe. 
Gen. The Rt. Hon. J. C. Smuts, P.C., C.H., F.R.S. 
I have been kindly invited to say a few words in this debate, with 
special reference to the philosophical bearings of the subject. I could 
have wished that a really competent philosopher had been selected for 
this task, as I am equally innocent of philosophy and mathematical 
physics. In a sense my Presidential address dealt with some aspects of 
the evolution of the universe, but a good deal more could be said, if there 
were time, about the philosophical issues which are raised by this subject. 
ee ee 
