156 
POLITICAL ECONOMY 
it is not inevitable and that the two countries 
might go on trading indefinitely without com 
parative costs in the two countries becoming 
the same. This is a perfectly valid objection, 
but if what is supposed happens, trade 
would continue until one industry had dis 
appeared in one of the countries at least. 
Let us postulate that trade does reach such a 
position ; that England sends to France 
100,000 pieces of cotton goods, and that the 
French cotton industry disappears. Let it 
be that the costs in England are 39s. for cotton 
goods and 20s. for wheat, their comparative 
values in France being 40s. and 19s. Then, 
if trade still increased in volume the value of 
cotton goods would fall in France, the cost of 
wheat rising, let us suppose, until comparative 
values in France were equal to comparative 
costs in England, or until farming disappeared 
in England, in which case each country would 
be left with one exporting industry only, 
and the quantity of exchanging between the 
two countries would advance until, under the 
operation of the law of diminishing utility in 
both countries, comparative values would 
become the same. We thus see that a limit 
at which comparative values are identical is 
inevitable. To this theory the admission of 
more countries and more commodities, and