This paper extends to economics the constructal theory of generation of sha
pe and structure in natural flow systems that connect one point to a finite
size area or volume. It is shown that by invoking the principle of cost mi
nimization in the transport of goods between a point and an area, it is pos
sible to anticipate the dendritic pattern of transport routes that cover th
e area, and the shapes and numbers of the interstitial areas of the dendrit
e. It is also shown that by maximizing the revenue in transactions between
a point and an area, it is possible to derive not only the dendritic patter
n of routes and their interstices, but also the optimal size of the smalles
t (elemental) interstitial area. Every geometric detail of the dendritic st
ructures is the result of a single (deterministic) generating principle. Th
e refining of the performance of a rough design (e.g,, rectangles-in-rectan
gle) pushes the design toward a structure that resembles a theoretically fr
actal structure (triangle-in-triangle). The concluding section shows that t
he law of optimal refraction of transport routes is a manifestation of the
same principle and can be used to optimize further the dendritic patterns.
The chief conclusion is that the constructal law of physics has a powerful
and established analog in economics: the law of parsimony. The constructal
theory extended in this paper unites the naturally organized flow structure
s that occur spontaneously over a vast territory, from geophysics to biolog
y and economics. (C) 2000 Elsevier Science Ltd. All rights reserved.