 After Opie gets cheated in a trade and intends to cheat another boy in return, Andy reminds him of "The Golden Rule" and tells him that honesty is the best policy. When the town council appoints Andy and Barney to sell an old cannon, they have no luck until an antique dealer comes through town. He is hesitant at first, but Andy makes up a history for the old gun and the man agrees to buy it for $175. When Opie follows Andy s example and trades a broken cuff link as a button off General George Washington s uniform for a pair of roller skates and money, Andy realizes he broke the golden rule himself and tries to make amends. The dealer still wants the cannon so Andy cuts the price to $20.