Glossary entry (derived from question below)
Spanish term or phrase:
Lo que es, no puede no ser
English translation:
What is, cannot not be.
Spanish term
Lo que es, no puede no ser
| 4 +4 | What is, cannot not be. |
Andres Diaz
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| 3 | what is, cannot not be, (what is not, cannot be, as nothing can come from nothing) |
Adoración Bodoque Martínez
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May 25, 2016 17:40: Michele Fauble changed "Level" from "PRO" to "Non-PRO"
Non-PRO (3): philgoddard, Graham Allen-Rawlings, Michele Fauble
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Proposed translations
United States
Thorough technical translations
Native in: English (Variant: US) 
Works in: Spanish to English
What is, cannot not be.
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Note added at 1 hr (2016-05-25 01:09:25 GMT)
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"Lo que es, no puede no ser y lo que no es, nunca los será, porque nada puede provenir de la nada" could also be translated as, "what it is, it cannot not be, and what it is not, it will never be, because nothing can proceed from nothing." I say this because it says "nunca los será" instead of "nunca será"
As Parmenides says: “it is and cannot not be.” What is cannot possibly be otherwise. What can exist does exist, indeed must exist.
| agree |
Francois Boye
14 mins
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| agree |
philgoddard
: Assuming it's 'lo que es' - 'lo que no es' doesn't seem to make sense.
1 hr
|
| agree |
bizisyl
10 hrs
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| agree |
Sophie Cherel
13 hrs
|
Ireland
B.A. Eng. & Ling., DipTrans IoLET, MCIL
Native in: Spanish (Variant: Standard-Spain) 
Works in: English to Spanish, Spanish to English
what is, cannot not be, (what is not, cannot be, as nothing can come from nothing)
"What is, cannot not be; and what is not, cannot be, as nothing can come from nothing"
Discussion
A.
(1) is no more logical than (2), given that, with (1), the sentence would thus read "Lo que es, no puede no ser y lo que es, nunca los será, porque nada puede provenir de la nada", which I would translate as "What is, cannot not be, and what is, will never be (them?) because nothing can come from nothing". Neither of these sentences appear logical to me, especially without any further context, but (2) would at least seem to have some kind of internal logic, i.e. a contrast between what IS NOT and what IS.
B. I am unable to find anything resembling this quote in your Parmenides translation link, or indeed anywhere else. It's almost as if it were some kind of parody.