Think of certain things you know for a fact.
 
Then ask how did you learn this fact?
 
Was it because people in authority told you, over and over, that it is a fact and you ultimately acquiesced to their declaration?
 
Or do you understand why it is a fact? Can you explain it without relying upon an appeal to authority? For example, , “well, 97% of scientists SAY it is true.. so it must be.”
 
That’s not understanding. It is regurgitation. It is indoctrination