Learning is a state transition from not knowing something to knowing it. Teaching is assisting someone through that state transition. To effectively teach someo

Learning is a state transition from not knowing something to knowing it. Teaching is assisting someone through that state transition. To effectively teach someone, you need an understanding of their current state as well as the trajectory of states they are capable of transitioning through. An expert is someone who knows the final state very well, but for whom the initial states and state transitions are a distant memory.