16 THE PRESIDENTIAL ADDRESS 
the problem which would have commended itself to many philoso- 
phers, from Plato to Berkeley, and is, I think, directly in line with 
the new world-picture of modern physics. 
I have left but little time to discuss affairs of a more concrete 
nature. We meet in a year which has to some extent seen science 
arraigned before the bar of public opinion; there are many who 
attribute most of our present national woes—including unemploy- 
ment in industry and the danger of war—to the recent rapid advance 
in scientific knowledge. 
Even if their most lurid suspicions were justified, it is not clear 
what we could do. For it is obvious that the country which called 
a halt to scientific progress would soon fall behind in every other 
respect as well—in its industry, in its economic position, in its 
naval and military defences, and, not least important, in its culture. 
Those who sigh for an Arcadia in which all machinery would be 
scrapped and all invention proclaimed a crime, as it was in Erewhon, 
forget that the Erewhonians had neither to compete with highly 
organised scientific competitors for the trade of the world nor to 
protect themselves against possible bomb-dropping, blockade or 
invasion. 
But can we admit that the suspicions of our critics are justified ? 
If science has made the attack more deadly in war, it has also made 
the defence more efficient in the long run ; it shows no partiality in 
the age-long race between weapons of attack and defence. This 
being so, it would, I think, be hard to maintain in cold blood that its 
activities are likely to make wars either more frequent or more pro- 
longed. It is at least arguable that the more deadly a war is likely 
to be, the less likely it is to occur. 
Still it may occur. We cannot ignore the tragic fact that, as our 
President of two years ago told us, science has given man control 
over Nature before he has gained control over himself. The tragedy 
does not lie in man’s scientific control over Nature but in his absence 
of moral control over himself. This is only one chapter of a long 
story—human nature changes very slowly, and so for ever lags 
behind human knowledge, which accumulates very rapidly. The 
plays of Aeschylus and Sophocles still thrill us with their vital human 
interest, but the scientific writings of Aristarchus and Ptolemy are 
dead—mere historical curiosities which leave us cold. Scientific 
knowledge is transmitted from one generation to another, while 
acquired characteristics are not. Thus, in respect of knowledge, 
each generation stands on the shoulders of its predecessor, but in 
respect of human nature, both stand on the same ground. 
These are hard facts which we cannot hope to alter, and which 
—we may as well admit—may wreck civilisation. If there is an 
avenue of escape, it does not, as I see it, lie in the direction of less 
