Everything you always wanted to now about Complexity

"The law of entropy tells us that the battle for simplicity is never over."
Roger Sessions.

All we now similar laconism about the problem of complexity. On the other hand, each Enterprise Architect knows, that our focus is to have a simple architecture. The real challenge behind this mission is that we are trying to optimise something what we cannot measure. The missing measure is the persistent doubtfulness if we go to the right direction. What is the solution?