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Design

2.16
Of the transient there is no endurance, and of the eternal there is no cessation. This has verily been observed and concluded by the seers of the Truth, after studying the nature of both.

According to the Śhwetāśhvatar Upaniṣhad, there are three entities in existence
bhoktā bhogyaṁ preritāraṁ cha matvā sarvaṁ proktaṁ trividhaṁ brahmametat (1.12)
[v13]
kṣharaṁ pradhānamamṛitākṣharaṁ haraḥ kṣharātmānāvīśhate deva ekaḥ (1.10)
[v14]
sanyuktametatkṣharamakṣharaṁ cha vyaktāvyaktaṁ bharate viśhvamīśhaḥ (1.8)
[v15]
All these Ved mantras state that these three entities—God, the individual soul, and Maya—are all eternal.
1. God is everlasting. Thus he is
sat
(eternally existing). Hence, a name for him in the Vedas is
sat-chit-ānand
(eternal-full of knowledge-ocean of bliss).
2. The soul is imperishable, and hence it is
sat
. However, the body will cease to exist one day, and hence it is
asat
(temporary). The soul is also
sat-chit-ānand
, but it is also
aṇu
(tiny). Hence the soul is
aṇu sat
,
aṇu chit
, and
aṇu ānand
.
3. The entity Maya from which the world has been made is eternal, or
sat
. However, all material objects we see around us came into existence and will be destroyed with time. Thus, they can all be termed as
asat
, or temporary. So while the world itself is
asat
, it is only the entity Maya that is
sat
.
When we say that the world is
asat
, this should not be confused with
mithyā
.
Asat
(temporary) does not mean
mithyā
(non-existent). Some philosophers claim that the world is
mithyā
, or “non-existent.” They assert that it is only the ignorance within us that is making us perceive the world, and once we are situated in
brahma-jñāna
(knowledge of the Supreme) the world will cease to exist. However, if this were true, then the world should no longer have remained for the God-realized Saints. Since they had destroyed their ignorance, the world should have stopped existing for them. Why then did these Saints write books even after attaining the state of God-realization? Where did the paper and pen come from? The fact that
brahma-jñānīs
use the objects of the world proves that the world exists even for them. Besides, even
brahma-jñānīs
need food to nourish their bodies. The Vedic scriptures state
paśhvādibhiśhchāviśheṣhat
[v16] “Even God-realized Saints feels hungry, just as animals do, and need to eat food.” If the world does not exist for them, then how and why should they eat?
Further, the Taittirīya Upaniṣhad repeatedly informs us that God is all-pervading in the world
so ’kāmayata bahu syāṁ prajāyeyeti sa tapo ’tapyata sa tapastaptvā idaṁsarvamasṛijata yadidaṁ kiṁ cha tatsṛiṣhtvā tadevānuprāviṣhat tadanupraviśhya sachcha tyachchābhavat niruktaṁ chāniruktaṁ cha nilayanaṁ chānilaynaṁ cha vijñānaṁ chāvijñānaṁ cha satyaṁ chānṛitam cha satyamabhavat yadidaṁ kiṁ cha tatsatyamityāchakṣhate tadapyeṣha śhloko bhavati
(2.6.4) [v17]
This Vedic mantra states that God not only created the world, but also permeates every atom of it. If God is truly all-pervading in this world, then how can the world have no existence? To say that the world is
mithyā
is to contradict the fact that God pervades the world. In this verse, Shree Krishna explains that the world does exist, but it is fleeting. Thus, he calls it as
asat
, or “temporary.” He does not call it
mithyā
, or “non-existent.”