Complex and complicated

Keith Hamon: As Edgar Morin points out so eloquently in his book On Complexity, we make a huge mistake when we try to reduce the complex to the merely complicated, or worse yet, to the simple. Actually, complicated and simple differ only in degree, whereas complex differs in kind from both. In one sense, both simple and complicated refer to a collection of fewer or greater elements in a particular, static arrangement. Complex refers to a collection of elements in an “infinite play of inter-retroactions” …

This distinction in knowing between the complicated and the complex makes a useful distinction between training to master a complicated concept or skill and teaching to master a complex discipline. … When we are learning the one and only right answer, then we are involved in training. When we are learning to probe open-ended questions with open-ended answers, then we are involved in teaching.

(source: http://idst-2215.blogspot.com/ )

I use the word Training for learning a skill. And teaching is about comprehension. Language and culture are complex systems, always uncertainty and misunderstanding.
In my view complexity means somewhere is uncertainty and one cannot make predictions. A complicated machine works in a predictable way. A complex system works but it shows surprises. Human behavior is complex, because it is to a certain degree not predictable.