The way that catharsis is related to Romeo and Juliet is that the moment of catharsis in the play occurs when Romeo and Juliet kill themselves.
Catharsis is emotional discharge after something tragic has happened. The audience usually cries and feels pity after something sad has happened, and that moment is called catharsis. So naturally, when these two young people kill themselves, it is quite sad and the audience feels strong emotions after their death.
He taught the colonists that they had natural rights as people which brought upon Thomas Jefferson writing Locke's phrase in the declaration of independence "Life Liberty and the Pursuit of Happiness"
i dont know if this is what the question is asking sorry if I'm wrong