I am here to prove how this happens in two different soliloquies and show you why Shakespeare put them into the play.
My first soliloquy is from Lancelot Gobbo and it is taken from Act 2 Scene 2.I know that Lancelot is a secondary character, but this speech is really important in the outcome of this scene. He is talking about if he should run away from his master, who just happens to be Shylock. This soliloquy has all the makings of what a soliloquy should do.
It creates the mood that Lancelot (Shylock's jester) is having a lot of
troubles trying to decide whether to run away or not. It must have a lot to do
with how Shylock treats him since he calls Shylock "a kind of devil" and also says that he can't handle being "ruled by the fiend." He must have really been mistreated under Shylock's care to go as so far as to run away from him. It creates the mood of sadness and hatred in Lancelot, and a dark evil kind of feeling towards Shylock for what he has done.
It develops the character that Lancelot is a hard working man who is just trying to make a decent living but cannot because of the way he is being treated by Shylock. It also shows us that Shylock may be the character that, in the play, is the character to fear. We don't know the details of what Shylock did to Lancelot so we have to cut him a little slack. But whatever he did to Lancelot has made him very angry and disgruntled.
And it develops the plot by starting off the main reason for this scene which is for Bassiano to get into the picture and for Gratiano to ask him if he can go to Belmont with him. It gets to this stage by Old Gobbo asking Bassiano if he will employ Lancelot, which he agrees to. It also tells of what to expect from Shylock in the later scenes which is unheartedness and ruthlessness.
My second soliloquy is taken...