| Quote #4
[…] but you must fear,
When Laertes advises Ophelia against premarital sex with Hamlet, he insists the young prince is not free to marry as he chooses because his nuptials must be good for the "safety" of the entire "state." Laertes is right – in the 16th century, folks didn't marry for the sake of love. It was common practice for powerful families to treat marriage as an opportunity to forge strategic political, social, and economic alliances. In other words, Laertes insists that a marriage between Ophelia and Hamlet is impossible. (It's funny, though, because Queen Gertrude later says at Ophelia's funeral that she had "hoped" that Ophelia would be her daughter in law – 5.1.1.)
| Quote #5
[…] Then if he says he loves you,
In the previous passage we saw how Laertes warns Ophelia that Hamlet is not free to marry for love. Rather, a prince's marriage must benefit (politically) the entire kingdom. What interests us here is the way Laertes also warns Ophelia not to give up her "chaste treasure" (her virginity) out of wedlock. If she sleeps with Hamlet, she'll lose her honor. Laertes isn't necessarily interested in giving any kind of moral argument on the ethics of premarital sex. He's talking about the way Ophelia's chances for a future marriage could be compromised if she loses her honor.
| Quote #6
As an unmarried daughter, Ophelia has no choice but to be obedient to her father. This means that Polonius is free to order Ophelia to break up with Hamlet. He's also free (later in the play) to use his daughter as bait in order to spy on the young Prince, which affords Polonius an opportunity to curry favor with King Claudius. This, of course, is a reminder that father's often use their daughters to negotiate strategic political alliances. (See 1.3. above.)