The question-answer format is a great way to teach and learn. Satsang is a diligent involvement on the part of the students in their quest for knowledge and an equally diligent involvement of the teacher who guides the search. So, we see Nachiketas pressing for answers from Yama in Katha Upanishad. We see the untiring Uddalaka repeating to Svetaketu about the nature of the Self. Uddalaka gives nine illustrations to show the equation between jiva and Brahmn which testifies to the kindness of vedantic teachers towards their students. Briefly then, it is this meaningful involvement on the part of the teacher and the taught that is called satsang.