your guess is as good as mine

[Theseus]

Would this English idiom approximate to θα μυρίσω τα δάχτυλά / νύχια μου και θα σου πω? Or is there a better alternative? Or have I misunderstood the Greek idiom?
Perhaps I should explain the idiom to those who don't know its meaning at the risk of teaching my grandmother to suck eggs!
The Cambridge Advanced Learners' Dictionary defines it thus:-
'​'Something you say when you do not know the answer to a question:
"What's he doing?" "Your guess is as good as mine."

 

[daeman]

...
Ό,τι ξέρεις εσύ, τόσα ξέρω κι εγώ. Όσο καταλαβαίνεις εσύ, άλλο τόσο καταλαβαίνω κι εγώ.

It's pretty straightforward as an expression, while the phrase with nail sniffing is similar but used mockingly, something like: "I'll consult the oracle and tell you".

 

[nickel]

Of course, the English idiom should be “My guess is as good as yours.” :)

Short Greek equivalent: Ό,τι ξέρεις ξέρω.
https://www.google.de/search?q="Ό,τι+ξέρεις+ξέρω"&sourceid=chrome&ie=UTF-8

 

[daeman]

...
Short Greek equivalent: Ό,τι ξέρεις ξέρω.

Nickel's guess is better than mine. If only I had written what came first to mind, without elaborating...

 

[Theseus]

Thanks daeman & Nickel. I know that both idioms are current but I think Nickel's English idiom is preferable to the one I posted, in that it is more logical. Thanks, daeman, for explaining the Greek saying. Apparently the expression is from the Olympic Games. I quote:-

'Κατά την διάρκεια των Ολυμπιακών κυρίως Αγώνων, είναι γνωστό πως οι θεατές στοιχημάτιζαν για τους νικητές, όπως γίνεται και σήμερα. Εκείνοι οι οποίοι ήθελαν να είναι «σίγουροι» για την πρόγνωση τους, επισκέπτονταν τα μαντεία προκειμένου να πάρουν και μια… δεύτερη γνώμη. Εκεί, οι ιέρειες, προκειμένου να προβλέψουν τους νικητές των αγώνων, βουτούσαν τα δάχτυλά τους σε ένα υγρό που φτιαχνόταν από δαφνέλαιο. Κατόπιν, έφερναν τις άκρες των δαχτύλων τους κοντά στη μύτη τους για να εισπνεύσουν το υγρό και έπεφταν σε ένα είδους ύπνωσης. Με αυτόν τον τρόπο μπορούσαν να δουν το μέλλον και να κάνουν τις προβλέψεις τους.'
Κάπως έτσι καθιερώθηκε μέχρι τις μέρες μας όταν κάποιος δεν γνωρίζει μια απάντηση να απαντάει με την χαρακτηριστική έκφραση «θα μυρίσω τα νύχια μου», αλλά και να κάνει την αντίστοιχη κίνηση.
I hope the above is acceptable Greek since it uses the word έτσι καθιερώθηκε μέχρι τις μέρες μας όταν κάποιος δεν γνωρίζει μια απάντηση να απαντάει με την χαρακτηριστική έκφραση «θα μυρίσω τα νύχια μου», αλλά και να κάνει την αντίστοιχη κίνηση.
I hope the above is acceptable Greek: it seems to overuse προκειμένου twice.:mellow:

 

[daeman]

...
Well, you said it, Theseus: "apparently". I'm not certain but that explanation seems to me a guess as good as anyone's.

With only a single source mentioning it and without valid sources to back it up, I would take it with a pinch of salt.
Goes well with laurel oil, too.

 

[nickel]

I too think the story is a fabrication, word for word.

 

[SBE]

Ι first heard the expression about sniffing one's nails from my flatmate at university. She grew up in Athens, I grew up in Patras. If the expression were in any way ancient or even old, I would have probably heard it before age 17. Needless to say, it sounded rather vulgar to me* and I never use it in my own speech.

*Maybe because my flatmate often derided me for my pronunciation and vocabulary, using expressions and slang unknown to me.

 

[Severus]

Another approximate translation would be "Beats me".

 

[daeman]

Another approximate translation would be "Beats me".

Agreed, of course. Nevertheless, that would be appropriate for a Greek > English thread where we would discuss the translation of a Greek phrase to English. In this one, the initial phrase is in English —by an Englishman, no less: Theseus— and a Greek equivalent is sought.

It's still useful, though.