Tom Ripley: You're the brother I never had. I'm the brother you never had. I would do anything for you, Dickie.
Freddie Miles: I want this job of yours, Tommy. I was just saying, you live in Italy, sleep in Dickie's house, eat Dickie's food, wear his clothes, and his father picks up the tab. If you get bored, let me know, I'll do it.
Meredith: Dickie?
Tom Ripley: Hello Meredith.
Meredith: Oh my God! I hardly even recognized you.
Tom Ripley: Well, you spotted me so you get the reward.
Tom Ripley: Nothing is more naked than your handwriting. See how nothing's quite touching the line? That's vanity.
Dickie Greenleaf: Well, we certainly know that that's true.
Dickie Greenleaf: Everybody should have one talent, what's yours?
Tom Ripley: Forging signatures, telling lies... impersonating practically anybody.
Dickie Greenleaf: That's three, nobody should have more than one talent.
Marge Sherwood: I don't believe a single word you've said.
Tom Ripley: You're shivering, Marge. Look at you, Marge. Can I hold you? Will you let me hold you?
Dickie Greenleaf: Now you'll find out why Ms. Sherwood shows up for breakfast, Tom. It's not love, it's my coffee machine.
Peter: Tom is crushing me.
Marge Sherwood: Tom was telling me about his journey over. Made me laugh so hard I almost got a nosebleed.
Dickie Greenleaf: Is that good?
Marge Sherwood: Shut up.
Dickie Greenleaf: I'm sorry. I'm sorry. I'm despicable. But I love you. Do you love me?
Dickie Greenleaf: How could it take an hour to find an ambulance?
Marge Sherwood: She was already dead, darling.
Dickie Greenleaf: I don't know why people say this country is civilised. It isn't. It's fucking primitive.
Dickie Greenleaf: You're so white! Have you ever seen a guy so white, Marge? Grey, actually.
Tom Ripley: It's just an undercoat.
Dickie Greenleaf: Say again?
Tom Ripley: You know a primer.
Dickie Greenleaf: That's funny. Margie likes that 'cause she's so white too.
Marge Sherwood: Yes, I do and you're not funny.
Dickie Greenleaf: "See Venice and die," is what they say? Or is it Rome?
Freddie Miles: Tommy. How's the peeping? Tommy, how's the peeping? Tommy. Tommy. Tommy. Tommy. Tommy.
Dickie Greenleaf: We're all only children. What does that mean?
Tom Ripley: It means we've never shared a bath. I'm cold, can I get in?
Dickie Greenleaf: No.
Tom Ripley: I didn't mean with you in it.
Dickie Greenleaf: Okay, get in. I'm like a prune anyway.
Herbert Greenleaf: You know, people always say that you can't choose your parents, but you can't choose your children.
Freddie Miles: In fact the only thing which looks like Dickie is you.
Dickie Greenleaf: You know, without the glasses you're not even ugly.
Marge Sherwood: The thing with Dickie... it's like the sun shines on you, and it's glorious. And then he forgets you and it's very, very cold.
Tom Ripley: So I'm learning.
Marge Sherwood: When you have his attention, you feel like you're the only person in the world, that's why everybody loves him so much.
Tom Ripley: And that's the irony, Marge. I loved you. You may was well know it, Marge: I loved you. I don't know... maybe it's grotesque of me to say this now, so just write it on a piece of paper or something and put it in your purse for a rainy day. 'Tom loves me.' 'Tom loves me.'.
Peter: Meredith Logue. You were kissing somebody. Looked like Meredith.
Tom Ripley: Hardly kissing. Kissing off, maybe.
Peter: That's not what it looked like.
Answer: After running into Meredith, Tom's plan was to stay in the cabin with Peter the entire trip to avoid them seeing one another. But after Tom makes that suggestion, Peter tells Tom that he seen him kissing Meredith. He couldn't avoid or kill her since Peter already saw her. Family members also saw Tom with Meredith. If Meredith suddenly vanished or was killed I'm quite sure there'd be an investigation. Peter was the only option. No one is on board to report Peter missing. Once the boat docks, Tom will be long gone before they discover Peters body. Unlike Meredith, her family would be looking for her immediately since they're traveling together. I'm quite sure he'd much rather have killed Meredith, she meant nothing to him.