How we cite our quotes: All quotations are from Harry Potter and the Half-Blood Prince.
Quote #4
SLUGHORN: Merlin's beard! Is that an actual Acromantula?
HARRY: A dead one, I think, sir.
SLUGHORN: Good God. Dear fellow, however did you manage to kill it?
HAGRID: Kill it? My oldest friend, he was.
This film's body count includes dear old Aragog, who terrorized the kids in Harry Potter and the Chamber of Secrets. Hagrid might be the only person who would be sad to see the spider go (including us)…but boy, is he devastated enough for everyone.
Quote #5
HARRY: Be brave, Professor. Be brave like my mother. Otherwise, you disgrace her. Otherwise, she died for nothing.
Whoa. Harry is really pulling out all the stops here in trying to get Slughorn to reveal some crucial information about his history with Voldemort. Slughorn was very fond of Harry's mother, so Harry uses her memory to his advantage here. Invoking her death and suggesting that Slughorn can give it meaning by spilling his guts? Dirty play, maybe, but it works.
Quote #6
SLUGHORN: A Horcrux is an object in which a person has concealed part of their soul.
TOM RIDDLE: But I don't understand how that works, sir.
SLUGHORN: One splits one's soul and hides part of it in an object. By doing so, you are protected, should you be attacked and your body destroyed.
TOM RIDDLE: Protected?
SLUGHORN: That part of your soul which is hidden lives on. In other words, you cannot die.
TOM RIDDLE: And how does one split his soul, sir?
SLUGHORN: I think you already know the answer to that, Tom.
TOM RIDDLE: Murder.
SLUGHORN: Yes. Killing rips the soul apart. It is a violation against nature.
TOM RIDDLE: Can you only split the soul once? For instance, isn't seven—
SLUGHORN: Seven? Merlin's beard, Tom! Isn't it bad enough to consider killing one person? To rip the soul into seven pieces! This is all hypothetical, isn't it, Tom? All academic?
TOM RIDDLE: Of course, sir.
Riiiiight, all academic. Btw, Slughorn really likes that whole "Merlin's beard" expression, doesn't he?
Anyway, this is the big convo that Slughorn had with Voldemort and then tried to cover up. Basically, Sluggy played a pretty big role in teaching Voldemort how to become immortal. Oops. No wonder he didn't want anyone to know what really happened between them.