Mac: Instead of doing a My Two Dads kind of thing, we'll do a Three Men and a Baby type of thing!
Charlie: Both equally effective movies.

Parenting is pretending you know what you're talking about, then jamming it down their throat!

Mac

Without the sunglasses, Weekend at Bernie's would have been a very dark, strange tale.

Dennis

God, what an irritating thing babies are!

Dennis

Mac: GOD! DAMMIT! Goddamn!
Dee: Nature is bullshit. I'm done with this.
Frank: I told ya, animals suck.

Dennis: That's all our money!
Charlie: No, it's all my money. You lost your money when you said no to the trucker.

This is for the rats!

Charlie

If animals have taught me anything, it's that you can easily die and very quickly under a bus and on the side of the road.

Charlie

Dennis: Do you have any money?
Charlie: Yeah, it's all right there. I put it all on black.

Dennis: We were hoping to be dropped off at a casino, this is just a motel.
Byron: I know. I thought we'd slip into a room and you could check my oil.

Animals can see souls. That is a fact of nature.

Mac

I named him Peter Peter Nickel Eater, because last night in the car he tried to eat a nickel.

Dee

It's Always Sunny in Philadelphia Season 6 Quotes

Dee: You've been really stressed so I thought I'd take you to a spa day. Just the two of us.
Charlie: A what day?
Dee: Spa day
Charlie: What is this word, spa? I feel like you're starting to a say a word and you're not finishing it. Spaghetti? Are you taking me to a spaghetti day?

Mac: Why are you jamming me up, bro?
Gym Manager: I'm not trying to jam you up, I just don't believe you.
Mac: What is not to believe? I'm absolutely Dennis Reynolds.
Gym Manager: This picture looks nothing like you.
Mac: Well, thank you, cause I've actually packed on about fifteen to twenty pounds of solid bulk muscle since that picture was taken. It's actually a testament to your gym.