Just saw Lal sir’s post actually I was writing before this post, Yes we can discuss this approach but I think ‘Time’ should be kept out of the question because this life stream X never started!, it must have graped human bhava because of some kamma bija in rupakkhanda. This is what I have explained in brief.
The reality is complex people tend to see it that it started somewhere but that’s not the case.
What I have understood is that we can put existence into Rupakkhanda and its analysis Vinnanakkhanda, and there is a Sanna cetasika which recognizes ‘things’ actually vedana also recognizes but there ‘recognition’ is different that’s why sanna is sanna and vedana is vedana.
I think this concept of something carried after death or perpetuating from one life to another shouldn’t be seen this way because no satisfactory answer we will get. why? because this one life to another is just one among many ‘illusions’ or rather ‘obvious perceptions’ which one gets when one see something at first glance like some may come across sense pleasures and say that these are created by god for man to enjoy but reality is VERY different.
Time is a big illusion, because we just created an extra entity for course of events happening to describe it. The sanna cetasika is what recognises things as ‘I’. Its takes the physical body as ‘I’ until someone sees his past life, when one sees the past life one sees another body and it thinks previously I was that now I am this but the point to be noted is that there are just two bodies and its upto ‘sanna’ to place what should be taken as ‘I’
Basically Rupakkhanda and its recognition Vinnanakhanda exists without any time like past, present or future. Just that Rupa makes contact with pasada rupa that making contact ‘phassa’ is Nama, so what can we say, Rupa is manifesting into Nama and Nama into Rupa. Rupakkhanda and Vinnanakkhanda is manifestation of one another, actually this concept of ‘one’ existing entity or in other words what ‘exists’ and what ‘do not exists’ cannot be resolved.
Now regarding your question its early people on the path think that even if I were to born again I will NOT be the same, so why to leave sensuality? This is like a paradox if NOTHING remains same in a given lifestream so how can we say that the two lifestreams are one? This thing cannot be resolved as I explained in brief, actually one can get insights if one has understood abhidhamma.
For Christian, I know you know these things should not be ‘speculated’ upon. And in general, If one really wants to understand ‘the existence’ reading abhidhamma would be enough. Then one will know that keeping the ‘reference frame’ right is important, when we say of a life stream that it is ever changing then how can we say there is a ‘perpetuation’ even? These two ‘contradictory’ statements are arising because we have kept the ‘reference frame’ wrong.
For ex: If one keeps ‘reference frame’ that a loving god created the world then why the world has suffering? This topic can be debated endlessly and creationalists may even provide ‘arguments’ in favour but as we know no satisfactory answer we will get. Why? Because reference frame is wrong.
Similarly world should always be seen terms of paramatthas rupa, citta, cetasika otherwise even Dhamma concepts MAY look contradictory. The right reference frame is to talk in terms of Paramatthas and without ‘time’ involved.
I will take a point of asanna satta you mentioned, thoughtless logs but how do we know? maybe any finer glowing body in our imagination which is made of the rupa we came in contact with eye base, and its recognition as ‘finer’. Someone with divine eye may see them, for that person they are still rupa and its recognition. If we think what might be happening with that asanna brahma, its still rupa and vinnana in our mind ( I used ‘our mind’ to emphasize, in reality, it is again rupa and vinnana).
Long story short, right reference is important because ANY reference other than paramatthas WILL bring contradictions and those cannot be resolved.