88 
POLITICAL ECONOMY 
on the side of supply by differentiating the 
experiences of businesses—their experiences 
as a whole—to use the phrase previously 
employed, just as it is possible to explain 
value on the side of demand by differentiating 
the experiences of consumers. 
The necessity of taking experience as 
a whole in our theorising may be emphasised 
again, now that we deal with it on the side 
of supply. Neither demand nor supply can 
be atomistically conceived. I do not know 
the utility of sugar when it is in my cup of 
coffee, but I do know the difference that it 
makes to the utility of the cup of coffee ; 
as a producer of steel I could not separate 
the cost of a particular ton of steel from the 
costs of other tons of steel made by me 
(because many tons of steel are made at a 
time by groups of productive factors working 
as a whole), but it would be theoretically 
feasible to calculate what difference its pro 
duction made to my total costs. However, 
it happens, as we have seen, that the cost 
per unit of output in a business comes on to 
the stage among the supply forces, and that, 
in relation to the marginal business, when 
supplemented in the manner already indi 
cated, it serves the purpose (the settlement 
of supply prices) which would be served in a