174 
POLITICAL ECONOMY 
amount per week that the payments made to 
him, plus interest upon them calculated up to 
the time when the harvest was sold, amounted 
to £50, or, in other words, he would receive the 
discounted value of his expected marginal 
worth, an allowance being made for the 
element of uncertainty as regards what his 
marginal worth would turn out to be. 
This doctrine comes to the same thing as 
the one previously laid down, provided that 
in our first enunciation we meant by marginal 
worth the anticipated worth, at the time when 
he was paid, of the result of the wage-earner’s 
work, in calculating which discount would 
have a place. 
Up to this point we have been disentangling 
the influences on the side of demand which 
help to fix the remuneration for employed 
factors in production. We have next to pick 
out the equally important influences which are 
active on the side of supply. These latter 
influences, we shall observe, are not the same 
for all factors. Let us take land to begin 
with. A comparatively fixed supply of land 
has been provided by nature for all time. 
For purposes of exposition let us picture the 
conditions on a small island, which has no 
intercourse with the rest of the world, and