The Best Way to Understand a Complex System Is to Draw It

A system is an interconnected set of people / things / ideas that is organized in a way that achieves something. We are surrounded by systems — schools, democracy, international trade, forests, cities.

One of the best ways to understand how a system works is to simply draw it out. Homelessness is a great example. Homelessness is caused by a complex interplay of housing prices, economic factors, addiction, mental illness, and racial inequities. Mapping out each of these factors one-by-one not only makes the system more understandable, but it can also reveal new insights.

#1 Housing

As you might expect, the housing market plays a huge role in causing homelessness. In short, over the last 40–50 years, various policies and activities have constrained housing supply, thus increasing prices:

• After WWII, government investment shifted to growing middle class wealth through home ownership. After decades of sprawling suburbanization, in the 1960s and 1970s new laws designed to slow the rate of growth (e.g. environmental protection, historical preservation, and local control of land use decisions) started emerging. While well-intentioned, these policies eventually empowered the “not in my backyard” (NIMBY) movement to block the creation of new housing.