there will be no motive to interchange.

"If the cloth and the corn, each of which required 100 days' labour in
Poland, required each 150 days' labour in England; it would follow, that
the cloth of 150 days' labour in England, if sent to Poland, would be
equal to the cloth of 100 days' labour in Poland: if exchanged for corn,
therefore, it would exchange for the corn of only 100 days' labour. But
the corn of 100 days' labour in Poland, was supposed to be the same
quantity with that of 150 days' labour in England. With 150 days' labour
in cloth, therefore, England would only get as much corn in Poland as
she could raise with 150 days' labour at home; and she would, in
importing it, have the cost of carriage besides. In these circumstances
no exchange would take place.

"If, on the other hand, while the cloth produced with 100 days' labour
in Poland was produced with 150 days' labour in England, the corn which
was produced in Poland with 100 days' labour could not be produced in
England with less than 200 days' labour; an adequate motive to exchange
would immediately arise. With a quantity of cloth which England produced
with 150 days' labour, she would be able to purchase as much corn in
Poland as was there produced with 100 days' labour; but the quantity,
which was there produced with 100 days' labour, would be as great as the
quantity produced in England with 200 days' labour.

"The power of Poland would be reciprocal. With a quantity of corn which
cost her 100 days' labour, equal to the quantity produced in England by
200 days' labour, she could in the supposed case purchase in England the
produce of 200 days' labour in cloth." But "the produce of 150 days'
labour in England in the article of cloth would be equal to the produce
of 100 days' labour in Poland [1]."