Grammatical structure of "goodness knows where"

Question

I encountered the following sentence (1).

(1) She came up from goodness knows where.

I wonder at the grammatical structure of "goodness knows where."

This phrase is used as a noun clause, but this word order cannot be understood as a noun clause according to the normal English grammar.

Do I have to accept this phrase as an idiom, or are there any grammatical explanations for this?

According to the normal English grammar, I think this should be written like this:

(2) She came up from the place which goodness knows.

Can (2) be used instead of (1)?

Answer 1

To answer your question directly, no; 2 cannot be used in place of 1.

The heart of the meaning here is that she came up from somewhere unknown to the speaker.

The speaker indicates this lack of knowledge by suggesting or asserting that there is somebody who knows where, but that (by contrast) it is not the speaker.

Some ways of expressing this are to say somewhere, nobody knows where, (only) God knows where, (only) "goodness" (as a stand-in for directly saying God) knows where. This is the sense which lies behind this phrase. Parsing by rules alone can result in constructions which do not convey the same meaning.

Neither is this a different way of asking the question. The speaker merely omits location information by asserting that it is largely unknown. The speaker has dismissed the location part of the travel as insignificant (and perhaps unsavory).

I agree with you that there is a problem with this construction if not seen as a phrasal element. I think (not sure about the nuts and bolts here) that this would benefit from the hyphen treatment for compound modifiers, e.g., goodness-knows-where, to mark it as a collective modifier, rather than a grammatical sequence. This way, we can simply call the whole thing an adverb of location and move on.

Answer 2

The correct version would be:

She came up from goodness knows where

Or

She came up from God knows where.

More alternatives for "goodness knows" are: Goodness/God/Heaven/Christ knows

If you say your second version i.e. "(2) She came up from the place which goodness knows. " then it will change your sentence meaning and will look odd. It would mean that: (Some 'goodness' knows where she came from).

Answer 3

That kind of statement is an inversion of the question, turning it into a statement, making the thing that is unknown a quality of the person, often with the implication that there is some sort of disrepute or at least a reason for mild disapproval:

Who knows where she came from?

She came from who knows where!

She blew into town from goodness knows where! That is, she is a free-spirit, a bohemian perhaps; she could have come from anywhere, the docks of Marseilles or the Louvre.

Or we could be speaking about Mary Poppins, and then the "disapproval" might just be that she's unpredictable; she just turns up all of a sudden, floating down into town on her umbrella.