OF VALUE. 
181 
toit. In either case, if they are steady in their 
operation, they may be equally regarded as 
causes of value. We may often assign an ef- 
fect to a cause, when perhaps we are unable to 
trace the exact series of changes occurring be- 
tween them, or, in other words, the less pro- 
minent links in the chain of causes and effects 
by which they are separated in time, but con- 
nected in efficiency. In reference to the present 
subject, this may be easily illustrated. The 
equality in the cost of production of two ar- 
ticles, for example, is a cause of their exchanging 
for each other. This we know is the general 
effect of such circumstances; but it would be 
difficult to trace with precision the mode in 
which the effect was produced, and which in- 
deed might vary on different occasions without 
disturbing the result. Suppose two persons, A 
and B, of whom the former has linen, which he 
wishes to exchange for woollen cloth, and the 
latter has woollen cloth, which he wishes to ex- 
change for linen. The matter would be abun- 
dantly plain, if, besides knowing what his own