Is non-emptiness empty?

Since Mahayana Agama contains parallels in the Pali Cannon I am answering using the Suttas in the Pali Canon which I am more familiar with.

Abiding or contemplating the 3 characteristics [impermanence (anicca), suffering (dukkha) and not-self (anatta)] is called abiding in emptiness. [Cula Sunnata Sutta, Maha Sunnata Sutta] The opposite of the 3 characteristics is perversions (vipallasa) [what is impermanent is taken to be permanent; what is painful is taken to be pleasurable; what is not self is taken to be a (or the) self; and what is impure is taken to be pure]. [Vipallasa Sutta] Hence non empty might mean something is deluded, i.e., conceptual constructions are empty since they breakdown under further scrutiny. Attachment to concepts, review and throughts or being subjected to the perversion is non empty.

Also:

Verse 11:

They take untruth for truth; they take truth for untruth; such persons can never arrive at the truth, for they hold wrong views.

Verse 12:

They take truth for truth; they take untruth for untruth; such persons arrive at the truth, for they hold right views. At the end of the discourse, many people came to be established in Sotapatti Fruition.

Source: Dhammapada Verses 11 and 12 Sariputtatthera Vatthu

Contrary to the usage on perversion described above someone taking untrue and truth, wrong view as right view, something of low value as valuable can be considered empty in this context and some one taking truth as the truth, ... can be considered non empty in this context.

There is a meditation that you can try to do to see this for yourself. If you are able to hold something in your mind like mental image of a teapot, or if you are able to chant a word or hold its spelling as a mental image in your mind, in this exercise it should have a meaning that you know and understand very well, you may be able to find your answer.

Focusing on mental images, even rotating them and manipulating them as your generated image becomes well defined and clearly visible in the mind with eyes-closed. Is just a trick to require your attention.

Same with chanting, there is actually a lot that goes into doing human language over and over again. Not just making the sounds but knowing what the mean and knowing that you have committed to repeating them, perhaps while also giving attention to your breathing, or sensations of energy occupying your physical senses.

There is a possible outcome in these types of exercising that is desired and rather shocking: your attention may or may not go away and then it will return causing the shock.

I believe the task continues to be held by some part of my brain controlling attention, but even though this is the same critical thinking type of consciousness it may eventually get automated out of your field of attention, like your heart controlling blood pressure or breathing.

Where we go during this moment, which may be as short a second or as long as minutes, I don't know.

But it is a place without time or thought, and you don't sense that you're there until you are abrubtly brought back to find this teapot or sound so well defined yet devoid of meaning. If you chanted, you will return to yourself making a sound for a word devoid of meaning and will be shocked by this.

Instantly your normal mode of consciousness will assign all meaning to the image or the sound, or the word. And this moment too, may be a fraction of a second or a few seconds, but it is a moment of bliss as you return from nothing to everything.

The bliss quick fades as your mind scrambles to reintegrate letters, sounds, words, meanings back into well defined and understood to be a certain thing.

I apologize for not know the vocabulary of these states, but I find they are the easier for me to access, and were once very easily repeatable. Also, leaving me with a certain buzz of invigoration and with a number of pleasing adjectives that seemed to indicate that I should move on from this.

I want you to see this because I believe it is a demonstration of the text you quoted, showing:

• your departure from your senses and the arrow of time
• your return from nothingness to your brain generating attention, only to find that it lacks any truth about your pre-departure definitions, as it hold no meaning and then instantly holds all meaning in a moment as bliss that guides you back to the construct of knowing meanings for things that we create, while understanding both nothing and everything one in the same.

Note: returning to find your self in the middle of vocalizing for me was a bit disturbing. However, I relied on it for a while just as it seemed to be easier to depart and more quickly. I started with oum, and eventually would play around with various words. Always the same effect, no matter how distinctly understood to be a discrete thing in our social construct. Holding images is just shocking to have a clear, vibrant contruct having your full attention, doubly so when you don't know what it is, and then triply so when you know it means everything. Same experience for chanting, but I eventually stopped chanting completely, as I felt like I didn't know what kind of fire I was playing with.

If non-emptiness means what it sounds like then it is indeed empty. All is empty within the reality of our individual experience. Everything that can be experienced is empty of self, complexity, and substance.

From a Madhyamika viewpoint, while emptiness [of true existence] is an existent, non-emptiness [of true existence] is a non-existent.

1. There is no fault in predicating a negation to a non-existent subject. For instance, you can say "Taking the subject 'a unicorn', it follows it is not white." Or "the horns of a rabbit lack this or that."
2. There is a fault in predicating a positive phenomena to a non-existent subject. This is because a valid knower can not realize a non-existent reason. For instance, you can not say "unicorns are white; rabbit's horns are made of ivory; non-emptiness is realized by way of this or that".

All in all, you can assert that non-emptiness is empty, because it amounts to associate a non-existent (i.e. non-emptiness) with a negative predicate (the lack of something).