# Complex Systems **John Gall**, in [*Systemantics: How Systems Work and Especially How They Fail*](https://en.wikipedia.org/wiki/Systemantics): > A complex system that works is invariably found to have evolved from a simple system that worked. The inverse proposition also appears to be true: A complex system designed from scratch never works and cannot be made to work. You have to start over, beginning with a working simple system.