Lyric discussion by edbanky 

Well, here's what I had gathered before reading the quote kindly provided by antileche above:

Mr Grieves is about (among other things?) evolution.

"You can cry, you can mope, but can you swing from a good rope?"

Meaning "being highly evolved, we can feel and emote, but we had to give up physical bonuses (of our nearest ancestors) like the ability to swing between trees."

"Pray for a man in the middle; one that talks like Doolittle"

This expresses the desire to be able to talk to animals, praying for a human - to - animal translator AND/OR it refers to "the missing link" in the evolutionary chain.

"I believe in Mr. Grieves" must just mean "I believe man evolved from the sea (to apes)"

"Do you have another opinion" challenges creationists?

"What's that floating in the water? Old Neptuna(e)'s only daughter"

Tough one, but possibly something to do with Neptune/Poseidon being god (Father) of the seas and water and oceans, and his "only daughter" being our first multi-celled or otherwise complex aquatic ancestor.

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So would say I got kind of close, although I never thought about it as "end of the world". From that perspective, I think most of the above still works.

You might notice similar themes (comaraderie with non-humans +/or the sea) in TONs of his songs, such as "Wave of Mutilation," "ANA," "The Sad Punk," "Where Is My Mind," "Monkey Gone To Heaven," "Caribou," "Bird Dream of the Olympus Mons," "Palace of the Brine," "Oh My Golly!," "Velouria" and "All Over The World."

@edbanky Perhaps it's refering to someone who can communicate with cetaceans, like porpoises, dolphins & whales which, by the way, I've been doing since 2018 & my surname is Greaves (OK, yeah, it's not spelt the same but hey ho).

I also just literally found out last night that Peter Capaldi [he's a British actor, in case you haven't heard of him] is playing a character called Gaius Grieves a.k.a 'the Thinker' who can read people's & animal's minds! So wow!)

I'm thinking Neptune's daughter is the 'Doolittle' character in the song

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