160 CAPITAL— THE MOTHER OF LABOUR. iv 



tion of the crop varies as widely in the case of 

 plant-raising as in that of cattle-raising. With 

 favourahle soil, climate and other conditions, it 

 may be very small, with unfavourable, very great, 

 for the same revenue or yield of food-stuffs. 



Thus, I do not think it is possible to dispute 

 the following proposition: the existence of any 

 man, or of any number of men, whether organized 

 into a polity or not, depends on the production of 

 food-stuffs (that is, vital capital) readily accessible 

 to man, either directly or indirectly, by plants. 

 But it follows that the number of men who can 

 exist, say for one year, on any given area of land, 

 taken by itself, depends upon the quantity of food- 

 stuffs produced by such plants growing on the area 

 in one year. If a is that quantity, and t is the 

 minimum of food-stuffs required for each man, 



■T^= n, the maximum number of men who can ex- 

 ist on the area. Now the amount of production 

 (a) is limited by the extent of area occupied; by the 

 quantity of sunshine which falls upon the area; by 

 the range and distribution of temperature; by the 

 force of the winds; by the supply of water; by the 

 composition and the physical characters of the 

 soil; by animal and vegetable competitors and de- 

 stroyers. The labour of man neither does, nor 

 can, produce vital capital; all that it can do is to 

 modify, favourably or unfavourably, the conditions 

 of its production. The most important of these 



