how does the process look like when an action is made or a thought is formed?
A crude contemporary anology, to reason could be, the One electric power, empowering different gadgets, (say with multiple functions) that would otherwise be defunct/inert, (without the electric power),though the mechanics of its functionality is vested in the gadget and not in the electric power.As any upadhi is inert , enabled by One consciousness, the only Sat.( Please ignore this if you already know).
Inquiry into the distinction between drg and drishya , delineated in the vedantic text Dṛg-Dṛśya-Viveka vividly, may answer most of the questions in relation to it.
Drg Drishya Viveka shloka 7
chaayaa ahamkaarayoh aikyam
tapta ayah-pindavat matam;
tat ahamkaara taadaatmyaat
dehah chetanataam agaat.
In the opinion of the wise, the identity
of the reflection (of Consciousness) and of ego is like the identity of the fire and the (heated)iron ball. The body having been identified with the ego (which has already identified itself with the reflection of Consciousness) passes for a conscious entity,
(Translation Swami Nikhilananda)
Here ayah-pindavat (also see Atma bodha ) is the typical example of mutual superimposition (anyonya adhyasa),where the shapeless fire takes the shape of iron ball , and the non-hot iron ball takes the heat of the fire, (known as taadaatmyaat ) hence creating the apparent appearance of sentiency propogating it to the body , causing an action to be made and thought to be formed,causing the karta , bhokta of samsaric experience.
Drg Drishya Viveka shloka 8
ahamkaarasya taadaatmyam
chit-chaayaa-deha- saakshibhih;
sahajam karmajam bhraanti
janyam cha trividham kramaat
The identification of the ego
with the reflection of Consciousness, the body and the Witness are of three kinds, namely, natural, due to (past) Karma, and due to ignorance,
respectively.
Natural - The moment the reflection of
Consciousness and the ego (Ahamkara) come into existence, they become identified with each other.
The ego manifests itself under the influence of this reflection. Therefore this identification is called
natural or innate. The experience resulting from this identification is,
I know (Aham Janami)
Karma -The ego identifies itself with a particular body according to its past acts, virtuous or otherwise. Birth in a particular body is always determined by Karma. The experience resulting from this identification is " I am man "
Ignorance- Ignorance of the real nature of Consciousness is called here (delusion) which is without beginning and cannot be described as Real
or Unreal '. This identification of the Ahamkara (ego) with the Witness
is based only upon ignorance This identification can be removed only by knowing the real nature of Consciousness. The experience resulting from this identification is, 'I exist'(Translation -Swami Nikhilananda)
Bhagavad gita shloka 9.29 in relation to Drg illuminating whatever happens.
samo ’haṁ sarva-bhūteṣhu na me dveṣhyo ’sti na priyaḥ
ye bhajanti tu māṁ bhaktyā mayi te teṣhu chāpyaham
The rainwater falls equally upon the earth. Yet, the drop that falls on the cornfields gets converted into grain; the drop that falls on the desert bush gets converted into a thorn; the drop that falls in the gutter becomes dirty water; and the drop that falls in the oyster becomes a pearl. There is no partiality on the part of the rain, since it is equitable in bestowing its grace upon the land. The raindrops cannot be held responsible for this variation in results, which are a consequence of the nature of the recipient. Similarly, Lord states here that He is equally disposed toward all living beings, and yet, those who do not love Him are bereft of the benefits of His grace because their hearts are unsuitable vessels for receiving it.
(Expln. Swami Mukundananda)
link between Dṛg and Dṛśya?
In the empirical world Drg. is one and drishya can be many, and they are different from each other and there should be atleast two entities , one to be called drg. and the other as drishya.
Drg. is always one (ekadha) casts modification /observation of the external world.