To establish advaidam nature of thuriyum, Gowdapadha is showing that thuriyum is not a kranam at all because any karanam is potential dwaidam to produce kariyam.  To establish this, Gowdabadha uses four methods.  In this portion of diversion, Gowdabadha strongly criticizes all dwaidin who believes that there is a creation born out of Brahman.  From an advaidin stand point:

• No creation is born out of Brahman or
• Apparent creation is born out of Brahman, meaning a real creation is not born at all.

Gowdapadha says dwaidin face many problems:

• Emotional: When duality will be real and ragha dwesha can’t be avoided creating samsara and sorrow.  Different point of views can’t be avoided, and each person’s point of view will be correct from that person’s point of view.  This is because of pramanam (instrument) used is different.  In the relative world of dwaidin, there will be differences.   Advaidin transcend reality and avoids raga dvesha; whereas a dwaidin can’t transcend relalty.
• Logical:  They all say paramtma or baghawan or Brahman is infinite, which means beyond time and space and not subject to modification.  It will be nirvikaram.  Whatever is not subject to modification, can’t be a karanam.  Therefore, infinitude and karanam status can’t co-exist.  Infinitude is nirvikarathvam (changeless) and karanatvam is savikaratvam (changing nature).  Therefore, infinitude and karanam can’t co-exist.  Therefore Baghawan, the infinite, can’t be a cause of creation.
• If Brahman is really multiplying to produce a creation, it will mean that infinite has become finite.  The changeless has become changing.  That beyond time has come within time.  This is logically not possible.

Verse 20

The disputants wish to ascertain the birth of birth-less Reality itself.  How can the birth less, immortal Readily indeed undergo mortality?

Gowdapadha wonders how all other philosophers don’t recognize this logical fallacy.  They claim that infinite, timeless, changeless, birth-less Brahman is changing when he produces creation, essentially making a changeless changing.  Brahman does not have any of the six modifications:  asti, jāyate, vartate, vipariṇāmate, apakṣīyate, and vinaśyati.  Infinite can’t become finite; finite can’t become infinite.

Verse 21

The immortal does not become mortal.  In the same way the mortal does not become immortal.  Transformation of the intrinsic nature does not take place anyhow.

Important verses, if you understand these verses, importunate of knowledge and moksha will be clear.

A finite thing can never become infinite and an infinite thing can never become finite.  Infinite can’t become anything because becoming itself implies change, within time and space. Will mortal become immortal or immortal become immortal? Mortal can’t become immortal by any amount of sadhana.  Immortal need not become immortal.  Therefore, moksha is dropping the struggle for moksha with the knowledge that I am already muktha.  If you are intrinsically mortal, don’t work for immortal because you will not become immortal.  If you are immortal, then you do not need to do sadhana for immortal.  If at all you do sadhana, it is not to become immortal but to own up the fact that I need not work for muktha; it is only for reminding that I am already a muktha.

Verse 22

If the intrinsically immortal Reality undergoes mortality for a person how can that immortality remain the same for him, since it is a product?

Two types of nature are incidental nature and intrinsic nature; hot coffee is incidental, because it become hot by contacting heat; it is subject to loss; if you keep the coffee outside it will become cold.  The heat obtained in fire is intrinsic and the fire will never lose the hotness.  Brahman infinitude is intrinsic nature and will not lose infinitude.  For the sake of argument, let us assume that the intrinsic nature also undergoes change.  We fell from paramatma and became jivatma.  Jivatma does the sadhana and one day the jivatma becomes paramatma.  If you become immortal paramata on a future date, that immortality is an event produced in future time.  But if Moksha or infinitude happens in time, that is also finite.  A moksha produced in time can’t be eternal.  The word moksha is permanent freedom from samsara and not a temporary freedom from samsara.  In the dualistic philosophy moksha will not be possible because for all of them moksha is an event in time.  Here intrinsically immortal Brahman becomes mortal.  If produced moksha can be eternal, then that will mean produced swarga can also be permanent.  Wherever there is a logical inconsistency, the dualist will ask you to believe.  A dualist says an moksha is an event in time and it is eternal.  Even though it is illogical, they ask you to belive it.  An advaidin says retain your intellect.  If moksha is an even time, it can’t be permanent.  Therefore, eternal moksha is a belief in dwaidam, and eternal moksha is only possible in advaidam.