by Hugh M. Lewis

Design modularization is intrinsic to the development of complex systems, and it concerns not only the prefabrication of replacement parts, but the possible substitution of parts with alternative components that may serve either a similar function, or a different set of functions in an manner integral to the framework of the system it is a part of as a whole. Design modularization may be thought of as the other side of the coin of the streamlining and convergence of systems upon an optimal solution set, and it concerns that natural divergence of elaborated and highly developed systems to a broad range of alternative conditions and circumstances, in a manner that is fitting and adjustable.

I would consider in general a highly modularized system to be one in which its components are highly interchangeable and in which its componential elaboration is relatively fine analytical scale. In developmental parlance we may call such a system as highly differentiated, hyper-compartmentalized and elaborated. There is a sense of association between componential elaboration of parts and the functional specialization of the part, which specialization may serve as a trade-off to the modularity of the component. A modular component should be definition be one that is replaceable not by an identical one, but by a different one of similar design configurations.

Standardization of certain design configurations is a way of overcoming this issue--if we know the make, model and year of a car, we can order different sets of tires by manufacturer and tread and construction, all fitting the same wheel drum in the same way. Rubber tires may be considered to be generally modularized even if the individual tires are somewhat specialized by tread, design, etc. The sizes of the tires are standardized across a range in order to fit a range of different vehicles and to allow for interchangeability of one brand of tire by another. If no interchangeability of tires were possible, there would be no market and no competition between tire manufacturers. Modularization might be correlated with certain kinds of network systems and certain patterns of market development in business systems. We would expect where design modularization is basic and of a high level, then there will emerge a broad range of companies that are competitive in meeting the demands afforded by a modularized market, however limited in scope this may be in the larger picture. Where high degrees of modularization are not permitted or achieved, we would expect there to be a tendency towards monopolization of a market by a single company.

A similar example of modularization are televisions, that all vary somewhat in design configuration, but which are capable achieving the same reception and display functions of the television signals it receives, covering the same sets of channels as any other television. The capacity to substitute one kind of television for another, and achieve more or less similar results, permits many companies to compete for the same market.

Design modularization is associated most definitely with processes of distributive integration and concomitant elaboration of meta-systems. It is a necessary feature in the development of large scale meta-systems permitting the heterogeneous incorporation of diverse component subsystems into a larger framework.

General Systems Essays, Vol. I