Issac and his friends are in search of a ship and finds a captain who isn’t current sailing. Issac threatens to kill the Captain and take the boat, but the Captain reminds him of how important it is to have the captain on the boat since he knows how to actual sail the boat. Isaac thinks that sailing a boat can’t be that hard, but the Captain points out that sailors exist for a reason. He is willing to sail Isaac and his friends as long as he is paid and promised not the be murdered. This scene is a good example of the double coincidence of wants and the importance of specialization and trade. The Captain has years of experience sailing ships while Isaac does not. It’s worth it to Isaac to trade coins for the Captain’s skills.
Thanks to Bryan Sloss for the clip recommendation