Conclusion to Part One

We have seen that Object-Oriented Programming is indeed, as many detractors suggest, a complex paradigm with many moving parts. We have also seen that this complexity is not essential: at its core is a single idea that a problem can be modeled as lots of distinct, interacting agents, and that each of those agents can be modeled as a small, isolated computer program. The solution to the original problem is found in the interaction between those agents, which is mediated by message passing.

Some of the incidental complexity seems to have been added by people wanting to make their mark: the proliferation in design patterns appears to have occurred because it is always easier to add a new pattern than to consolidate existing ones; however much some people might like to erase Singleton from history. Objects are not "just" decomposition and message-passing, they are that and providing access to a program's data, or that and a hierarchy of classes.

Much of the...