32 THE SHADOW OF THE WORLD'S FUTURE 
season for them, must not be less than a certain 
minimum. Finally, the crop produced must at least 
pay for the labour of cultivation. In connection with 
this last condition, however, popular ideas as to what 
constitutes a “ reasonable standard-of-living ” affect 
the issue. This covers not merely food, according 
to some “dietary standard,” but clothing, housing, 
education and the whole paraphernalia of social life. 
These are the governing conditions previously referred 
to. 
In this connection it may be mentioned that although 
the American “ dietary standard ” is a cheap balanced 
ratio consisting largely of vegetable products, the 
energy-value of which is 3500 calories per diem, it 
cannot be regarded as in any way representing a world- 
average. The standards of the Chinese, Japanese and 
Hindu masses are, of course, much lower than this. 
Even that of Europe is only about 3000 calories per 
diem. 
In regard to living-standards, too, it may further be 
said that if, as appears to be already beginning, the 
multitudes of the East should westernise their con- 
ceptions as to what constitutes a reasonable standard, 
the population-problem is at once raised to a plane of 
greater difficulty. On the other hand, if western races 
ever abandon both their present love of what may 
seem to some inordinate luxury, and all useless com- 
plication of the paraphernalia of social life, it is certain 
that the population difficulty, for a time at least, will 
diminish. It is also temporarily diminished by every 
betterment in the organisation of human effort in 
production and distribution, and by success in insuring 
against the vicissitudes of Nature, which often, in 
quite a little while, wreck the effect of long periods of 
effort. Some of the countries considered are subject 
to repeated periods of calamity. 
Turning now to the light which American research