Antonio and Sebastian - Act 2, Scene 1

Antonio is the current Duke of Milan and is the brother of Prospero.

Sebastian is the brother of Alonso, who is the King of Naples.

The scene begins with a speech from Gonzalo, optimistically pointing out how they have survived the storm and how the group should all bring comfort out of this.
Within Antonio and Sebastian's first lines in this scene we see their true pessimistic, obnoxious and  devious personalities.

Sebastian: (apart to Antonio) [Alonso] receives comfort like cold porridge.
Antonio: (apart to Sebastian) The visitor will not give it him o'er so.

Shakespeare presents the characters discount of the correct hierarchy, Sebastian is privately mocking not only his brother but also his king. As the audience you already begin to understand the lack of respect these men have for anyone but themselves.

Antonio and Sebastian then continue to mock whatever Gonzalo says privately, whilst Gonzalo remains positive in his view of the island and trying to make the best out of the situation. Antonio and Sebastian laugh at him and see only the bad in their situation.

Their ridicule of Gonzalo makes the audience question, who is telling the truth?
We are made to believe that Gonzalo is a very knowledgeably man and, as we found out in Prospero's monologue to Miranda, we know he was kind enough to put himself out his way to make sure they had food and books for their exile.
Yet, Gonzalo is ridiculed by the two men, they call him an 'old cock' and mock his every opinion which inevitably makes the audience also doubt Gonzalo.
In line 65-67, Shakespeare uses Gonzalo to inadvertently explains to the audience how all these Dukes and the King came to be travelling rather then in Naples. They are all returning from the marriage of Alonso's daughter to the king of Tunis.
From this the audience is again made to doubt Gonzalo because of Antonio and Sebastian.
Gonzalo compares the new queen of Tunis to widow Dido, queen of Cathage and famous figure in Greek mythology, which shows that he know and has read his myths yet he is flawed.

• Widow Dido was queen of Carthage which is close to the city of Tunis, Gonzalo has got confused between the two cities.
• In one of the versions of this myth Dido kills herself after she is rejected(widowed) by her lover Aeneas. Therefore she is not a true widow and would actually of been seen as 'evil' for having an affair.

Antonio and Sebastian pick up on these things are argue and mock Gonzalo because of it. It does make you as an audience start to see Gonzalo as less knowledgable than he makes out and more like the 'old cock' that will witter on as Antonio and Sebastian make out he is.