Fish fish fish eat eat eat <- for real?

Question

Consider the following sequence of (supposed) sentences:

• "Organisms that fish eat are tasty" is valid English sentence.
• "Organisms that fish eat, eat." is also valid English sentence, although it's getting confusing.
• "Fish that fish eat, eat." more confusing, but still valid.
• "Fish that fish eat eat." Could I really have dropped the comma here?
• "Fish fish eat eat." Could I really, legitimately, have drop the definite article here?

If you've accepted all of the above, then surely you must conclude that:

"Fish fish fish eat eat eat" is a grammatically correct sentence in English.

but how can that be? It's super-confusing. Isn't there some principle limiting the depth of this nesting-of-phrases?

Answer 1

This is what one paper calls a "multiple self embedded sentence":

We have [a self-embedded (SE)] sentence when a phrase is placed totally within another phrase of a similar type, e.g., (1) The nurse that the cook saw heard the butler. A multiple SE sentence has a phrase within a phrase which is in another phrase, e.g., (2) The nurse that the cook that the maid met saw heard the butler. The latter example is definitely unacceptable to speakers of English. People have difficulty in pairing the verbs with their subject nouns, if indeed they even get as far as recognizing that the words comprise a sentence.
_{Observations with self-embedded sentences}

(The other thing that is happening in your sentence is that "that" is being dropped.)

These are theoretically valid sentences, but are very hard to parse and therefore are unacceptable to most people.

You can create similar sentences yourself by writing write a valid sentence using a placeholder pronoun ("the man {she} loves is gone"), then replace that pronoun with something. Said something that's replacing the pronoun can be another phrase, itself using a placeholder pronoun ("a woman {he} knows"), and then you can repeat this infinitely ("the man {a woman {a child {another boy} saw} knows} loves is gone").

Answer 2

I can make this work grammatically, but you REALLY have to squint at it.

I'll break it down for you.

Fish eat. This is a simple sentence. Fish (n) eat (v).

Fish fish eat This is not a sentence. It's a noun phrase. (Fish that other fish eat.)

Fish fish fish eat. This is a sentence. [Fish that other fish fish for] (noun phrase) eat (v).

Fish fish eat eat. This is a sentence. Fish who are eaten by other fish (noun phrase) eat (v).

Fish fish fish eat eat. The fish which (fish who are eaten by other fish) eat. -- Noun phrase.

Fish fish fish eat eat eat. - The fish which get eaten by (fish who are eaten by other fish) (very complex noun phrase) eat(v).

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This is comparable with the famous buffalo sentence.

I won't unravel that here. But, it's worth a read.

Answer 3

Yes, the above sentence is grammatically correct. As explained in the source you linked, this is by omitting various instances of 'that'. The meaning of the sentence is: 'fish that eat other fish, which in turn eat other fish, eat'

To prove how grammatically correct 'fish fish fish eat eat eat' is, we start with a simple clause: fish eat.

To turn that into fish fish eat eat, we merely modify the subject (fish) to be 'fish [that fish eat]', and by omitting the 'that' we are left with fish [fish eat]. Reinserting this modified subject into the original clause, we are left with 'fish fish eat eat'

This logic can be applied again, this time modifying the modifier of the original subject of the clause - this time, clarifying that the subject of the phrase 'fish eat' aren't merely eaten by other fish: they are eaten by fish that are in turn preyed upon by other fish.

This results in the clause 'fish [(that) fish [(that) fish eat] eat] eat', which can be simplified down to 'fish fish fish eat eat eat'.

This logic can be applied indefinitely, resulting in a nearly-nonsensical phrase that has almost no applicability outside the realms of:

(a) Extremely specific biology and describing the actions of fish at the bottom of the food chain and

(b) Instances such as these

Answer 4

FISH Fish fish eat Eat EAT

Fish [the fish (that fish eat) and eat] then eat. You eat [fish (eaten by fish) that eats fish].