First line - Till the son is five years old one should pamper him. When he crosses five till he becomes 10 he should be spanked. (Tadayet means to spank) in reality those are the years when one needs to discipline him.
However, when he turns 16, he should be treated like a friend. ( Means he should feel that he is grown up and his opinion matters, which can happen when he is treated like a friend.)
A fully filled water container will not create much noise as compared to the half filled one. (When the containers are given some jirk the water inside it will also move and create some noise.). Similarly 'Vidvaan' (Intelligent) people always remain calm and will not have any mis-placed pride as opposed to the people who know very less but always keep talking.
This is from Mahabharata, encounter of Yudhishthira with Gandharva. Gandharva asked Dharmaraja(Yudhishthira), what is the most surprising thing on the earth. In response to this, Dharmaraja gave this answer.