How is consciousness measured?

What about all the perfected ones, the fully awakened Buddhas who lived in the past? Have you comprehended their minds to know thatKiṃ te, sāriputta, ye te ahesuṃ atītamaddhānaṃ arahanto sammāsambuddhā, sabbe te bhagavanto cetasā ceto paricca viditā:those Buddhas had such ethics, or such qualities, or such wisdom, or such meditation, or such freedom?”‘evaṃsīlā te bhagavanto ahesuṃ itipi, evaṃdhammā te bhagavanto ahesuṃ itipi, evaṃpaññā te bhagavanto ahesuṃ itipi, evaṃvihārī te bhagavanto ahesuṃ itipi, evaṃvimuttā te bhagavanto ahesuṃ itipī’”ti?

“No, sir.”

https://suttacentral.net/dn28/en/sujato

I asked a similar question in Dhamma Wheel.

Can stream of consciousness naturally come to an end?

https://www.dhammawheel.com/viewtopic.php?f=13&t=36287&hilit=Infinity+consciousness

Good householder,

infinitive means that it has no border, no end, not even a perception of such. And like Upasaka Vorapol (Bonn) tried to transmit. Coming from a merely outwardly infinitive perception of space, the object, one turns at this stage toward the "subject", the consciousness, that of what knows, be aware of, mind. And of course, at least philosopical, infinitive is not measureuable.

Of course one can categorize diverent perceptions, individual, conventional...transcendent and sort them into minor and more sublime, like as from blurry to sharp.

After infinitive "mind at knowing" one turns to even more sublime perceptions, giving up knowing as well.

To get things really known, one needs to practice: Sila, Dana, Bhavana (reflecting the heard Dhamma). Concentration is something that has a cause, would not arise without. So one concentrates on give the cause for it.

[Note that this isn't given for stacks, exchange, other worldbinding trades, but for escape from this wheel]

These two infinite spheres that you ask about are the same.

They are the same because they are imaginative attempts to conceive of something about reality: one which you say you can comprehend, and the other you ask about so that you can comprehend it.

They are the same because ultimately, they speak of reality, which has no pieces, aspects, parts, characteristics, etc. Only that which is held to occupy space is like that.

You say you can comprehend infinite space but that is not reality. It is an artifact of modern science which conflates infinite time and space together as spacetime in order to attempt to define the ‘laws’ of motion of things that inhabit space-time. Thus you see it as something that will take ‘forever’ to traverse. If that is what you want to comprehend, you should seek out Physics Stack Exchange.

You have trouble with “infinite consciousness” because you have been confused by scientists who, limited by their understanding of reality as just a big space-time filled with things that interact physically, consciousness must be in the brain. Thus, how can it be infinite.

But these two ‘spheres’ mean “not-limited”. What is not limited? Even the universe of science has edges, and thus, limits. So in that realm, you must always envisage another ‘level’ of reality that contains the lower level.

“Not-limited” means not conceptualizable, not comprehensible, by intellect.

To properly understand these statements about that which is not limited by the intellect, which are made, not in an attempt to describe something, but rather, to point the way forward for the understanding as it develops through a meditative practice, is to meditate, meditate, meditate.

And that process is unlimited in what it can bring.

Consciousness cannot be measured. Because all is measured by itself, but measured things cant measured the instrument of measurement i.e. consciousness.

Consciousness is a pool of whole, we are part of that. When individual consciousness ceases altogether, with cessation of I, it finds itself a part of universal consciousness. So, then question of coming & going, being & nonbeing ceased totally. He see all beings are part of him. He doesn't harm any creature with his body, mind and speech. (Human beings are exactly the same, wherever you go. We are one single unit, but due to ignorance perceive different than others. That's where the work of Religion starts, to bind the world together as one family.) Peace!

Everything depending on their causes. If you want to know anything you need to know their causes and effects, so you should comprehend both spheres' dependent origination to understand them both.

What are you talking about is the object of consciousness. Consciousness in 30 spheres are knowing the object.

When the meditator meditated, did karma, infinite-space-meditation. This karma is going to create the only Nāma, resultant consciousnesses and mind factors. This Nāma has infinite-space illusion as object too. There are the other Nāma in Arūpa too, but not it's resultant. So...

There is a sphere of infinite space

It is a sphere of the consciousness being which knowing the object, infinite space.

there is sphere of the consciousness.

It is a sphere of the consciousness being which knowing the object, consciousness which knowing infinite space.

What is infinite space?

The infinite space is the special illusion which created by the 4th jhana master's mind when he practice infinite space jhāna.

Without the fourth jhāna, you can not create this illusion by yourself.

Why it is called in finite space?

Because the forth Jhāna master uses the space between Kasina to be basis of this Jhāna and because this is no matter, Rūpa, so the forth Jhāna master must ignore Kasina, which basing on Rūpa, by knowing only space illusion.

What is infinite consciousness?

There is no infinite consciousness actually. In the KN. Patisambhidamagga's commentary there is two definition...

anantaṃ viññāṇanti taṃyeva ‘‘ananto ākāso’’ti pharitvā pavattaṃ viññāṇaṃ ‘‘anantaṃ viññāṇa’’nti manasikarontoti vuttaṃ hoti. manasikāravasena vā anantaṃ. so hi taṃ ākāsārammaṇaṃ viññāṇaṃ anavasesato manasikaronto anantaṃ manasi karoti.

1. The consciousness which knowing the consciousness as object. This object is consciousness which knowing infinite space, so it is called infinite-(space-object-)-consciousness.

2. The consciousness which knowing uncountable consciousness as object. This object is uncountable
   space-object-consciousness, so it is called infinite-(space-object-)-consciousness.

It is easier to go to Pa-Auk forest monastery to practice it directly 😊🧘

But if you want to understand by reading, see the path of verification in SamādhiNiddesa.

To measure is to assess. Consciousness exists to assess, to make choices. One assesses to gain more. Gaining more, consciousness grows. The measure of consciousness is what we gain.

DN15:15.2: Suppose there were totally and utterly no assessing for anyone anywhere. When there’s no assessing at all, with the cessation of assessing, would desire and lust still be found?”

Suffering creates limits:

SN41.7:6.2: Greed, hate, and delusion are makers of limits.

So we have then an apparent paradox with "infinite consciousness." How can consciousness be infinite if it is limited by assessment?

Infinite consciousness cannot be measured or assessed because any such measurement or assessment would be a limit. But infinite consciousness can be perceived.

AN9.41:13.10: ‘Suppose that, seeing the drawbacks of the dimension of infinite consciousness, I were to cultivate that. And suppose that, realizing the benefits of the dimension of nothingness, I were to develop that. It’s possible that my mind would be eager for the dimension of nothingness; it would be confident, settled, and decided about it. And I would see it as peaceful.’

Please keep in mind my answer comes from my personal experience alone, and not from a study of Buddhist texts. Also, I want to establish terminology because conversations like this can get very confusing if we aren’t extremely clear about what we are talking about.

When I say consciousness, I am talking about a specific sensate experience I can most directly explain as a combination of lucidity and identification. In my experience, consciousness is impermanent. When I am conscious, I am most likely observing thoughts who’s content kick off a process of identification (I am this not that, etc). I identify as a particular aspect of experience when conscious. In a deep sleep when I am aware of only awareness itself, consciousness is not present. But once the automatic process of self identification occurs upon waking, consciousness tends to arise.

The quality of “lucidity” that is present in consciousness is one that I can only describe as “the will or ability to act”. When I am lucid, I feel as if I now possess the ability to freely act, like during waking experience. When I am not lucid, I feel experience and actions are occurring autonomously, like during a dream.

Based on my definitions I would say the following.

When I am in a deep sleep, I am aware but not conscious. There are no experiences to identify as and I have no will to act.

When I am dreaming I am aware but not conscious. There are experiences to identify with, but there is no will to act.

When I am lucid dreaming I am aware and conscious. When I am awake I am aware and conscious. In both there are experiences to identify as and I have the will to act.

So to finally answer your question now that terminology has been laid down.

It is easy to comprehend what is infinite space is but it is not clear what is meant by infinite consciousness? Does it mean infinite history of experience? Or does it mean infinite presence of sentient beings with consciousness?

In my experience, it doesn’t mean either of the options you suggested, if I’m understanding you properly.

Whenever infinite space and infinite consciousness are paired together in conversation, I always immediately think of the altered states of consciousness that arise during deep concentration meditation. Specifically two particular Jhanas.

Infinite space is very clearly known during what I call the 5th Jhana. In this state, most of the 6 senses have dropped away, but I am left with a feeling of being a single point of consciousness, sitting within an infinite space. I physically feel the experience of space all around me, that seemingly goes on forever. The experience of consciousness is very small in this state in comparison to the experience of space.

Now in the 6th Jhana, I experience what I would call “infinite consciousness”. In this state, the single point of consciousness shifts into the space. Consciousness no longer feels like a point within space, but feels as if the entirety of infinite space is conscious/who I am. Some people describe it like the space becomes luminous, which I wouldn’t disagree with. If the previous state was described as “a point of consciousness within a sphere of infinite space”, this state would be described as “a sphere of infinite space that is conscious”.

There are other explanations of what could be meant by infinite consciousness, but they are normally talked about by people with different definitions of consciousness. When people talk about infinite consciousness from the pre-enlightenment perspective, This is what I believe they are referring to.

As i understand it, It is like perception of infinite space but without the space. There is then only the conception & perception of a boundless pleasantness.

There is the concept of infinity in play, consciousness is delineated due to the pleasantness of it's [boundless] perception.

In MN121 the Buddha explains his step by step method for achieving Liberation or Nirvana. This method relies on the gradual removal or abandonment or "giving up" of objects and any boundaries/limits, any separation, any division. First, the gross objects/limits/separation is removed, then medium-gross objects/limits/separation is abandoned, then subtle objects/limits/separation is "given up", and this process of incremental iterative refinement is repeated and perfected all the way until Final Liberation.

This process can be compared with a loop in a software program, a cycle:

var A = AttendTo(any object);
repeat until(A==Nirvana){
    var notA = FindComplement(A);
    A = AttendTo(A + notA);
}

On each iteration of this loop our current object is A. Next, we find its counterpart, the NOT A. Next, we combine the total of A + NOT A and make that our new A. This is repeated until Nirvana.

The first step of that process is to start where you are. Let's say you are looking out of your window and see a parking lot with cars and people. When you focus on one of those people, that's an A. When you focus on another person, that's another A. Any single person or any car can be your object. Then you try to find the counterpart (or the mathematical complement) of that A, the NOT A. If you take one member of a mathematical set, then the complement is the rest of that set. If you take any one object (person or car) on the parking lot, then its complement is everything else on that parking lot except that first object. Next step is to put together A + NOT A and make that your new A. When we combine our first person with the rest of the parking lot, the resulting A = A + NOT A is "the entire parking lot". This is the end of the first iteration.

The next iteration is when our A is "the entire parking lot". The NOT A is the rest of the world. The A + NOT A is "the entire planet".

The next iteration is when our A is "the entire planet". The NOT A is the rest of the universe. The A + NOT A is "the Infinite Space". The reason it's called "infinite" or "boundless" or "limitless" is because it is spatially all-inclusive without any borders or separation. It is our first serious attempt at attaining an undivided meditation object.

The next iteration is when our A is "the Infinite Space". This is where it gets a bit more tricky. What is the NOT A, what is the complement of the Infinite Space in an even broader context? Can we expand from the Infinite Space even further out? In other words, if the A of Infinite Space is one member of a larger set, then what could those other members be?

(...drum roll...)

The other members are all other phenomena, all other contents of our consciousness! Then A = A + NOT A is the entire consciousness with the entire totality of all its possible states and objects. When this becomes our new A, our new object of our iterative meditation refinement process, this stage is called "The Infinite Consciousness". Again, the reason it is called "infinite" or "limitless" or "unbounded" is because it is our new standard of all-inclusive undivided object of meditation.

The next iteration of this goes as follows. If A is The Infinite Consciousness, then what is its counterpart? What is beyond all phenomena, beyond all states of mind, all contents of consciousness? It is the complete absence of any content, complete Nothingness. This is our NOT A. And what is the superset of both A and NOT A? It is that which includes both "entire realm of conscious experience, with all its possible states" and "the complete absence of anything". This A + NOT A is called "the realm of neither (just) perception nor (just) nonperception", in other words it is the common ground for both consciousness and nothingness. But what is it, really? It is the point of view that comprehends all conscious experience as well as comprehends nothingness. It is the ultimate reference point.

Finally, taking this last object as an A, we need to work harder to find its complement. Could there be anything beyond the ultimate reference point that comprehends both consciousness and nothingness? It seems impossible to imagine. However, if you look very-very carefully you can realize that this ultimate reference point is nothing but a sign of "I", the sign of "subject". The complement of that A is complete cessation of I-making, complete cessation of being a point of view. Which means, it is complete cessation of interpretation, evaluation, discernment, and recognition, complete cessation of semiosis. This NOT A of "neither perception nor non-perception" is traditionally known as "cessation of perception and feeling". And if we combine these A + NOT A, that is if we find the common ground of both, then finally we are done.