(book) Thinking in Systems

Thinking in Systems -- by Donella H.Meadows

The behavior of a system cannot be known just by knowing the elements of which the system is made.

You think that because you understand "one" that you must therefore understand "two" because one and one make two. But you forget that you must also understand "and"

Watch out! If you see feedback loops everywhere, you're already in danger of becoming a systems thinker! Instead of seeing only how A causes B, you'll begin to wonder how B may "also" influence A - and how A might reinforce or reverse itself.