what is the consciousness that does not get destroyed then?
I understand it's free of aggregates, clearly these fall apart with the body that dies - but what is stored in the consciousness to move on - the delusion itself?
My understanding is that "consciousness", and by that I mean any level of cognitive awareness, whether it's arising as that of a rocket scientist or a moth, is not a single thing, but a series of separate simultaneous events, and those events trigger more separate simultaneous events which, because they are caused by particular ones, closely resemble the ones that cause them. It's sort of a domino effect.
"Consciousness" therefore only appears as a thing which is somehow stored.
One might ask, "well what about the alaya vijnana, or 'storehouse' consciousness?"
Or somebody might ask, "how does a person remember who they are after coming out of a coma where all streams of consciousness seem to have been temporarily cut off?"
But storehouse doesn't mean that there is a physical place. It too refers to an active series of events.
Why would thoughts, which exist only for durations of time, need a physical space?
Delusion is also not a thing. So, since it is not a thing, "it" doesn't move on.
If you can't find your house keys, and a minute later you still haven't found them, you don't say that not knowing where your keys are is some thing that moves on. So, delusion is like this.
If a person doesn't know something, or has a deluded understanding about something from one moment to the next, or from one "lifetime" to the next, it is simply because the delusion continues to be caused by the same cause. It has the same cause to continuously occur, But it is not a 'thing' which is delusion that is moving.
Consider the analogy of a flame burning down the length of a candle. it looks like the same flame from the moment you light it until the candle is gone. But in fact, the flame needs both oxygen and fuel (wax & wick), the molecules of which are being gradually, yet continuously consumed, one after another (or perhaps in great batches, like laundry).
The candle doesn't combust all at once. It only appears to be the same flame the whole time the candle is "lit".
From the view of somebody simply looking at the flame, it might as well be called the same flame. It functions for our needs as one continuous flame. But on the molecular level, the heat is just causing a seemingly endless parade of molecules to sort of burn up. The heat from one part of the candle warms up the next part to the point where it heats up the next, on and on and on, until the candle is gone.
So, you could say that one thought (you could think of it as a particle of thought) ignites another, in a seemingly endless parade of thoughts. The difference here, however, is that the causes of thoughts don't actually need physical substance the way a candle flame needs wax and wick. They aren't what we would even categorize as "thoughts" until they arise with a little help from the brain.
So, what are these "causes" of thoughts? Everything!
Everything appears as thought only when the circumstances are right.
That happens when your senses or imagination combine with an object.
Until then, it's like "out of sight, out of mind". The thought does not exist.
It's like reflections of things only appearing in mirrors when those things are placed in front of mirrors.
It's like putting the Mona Lisa painting in a room with no light source. Without light, there are no colors and without colors, there is no Mona Lisa. But the causes of Mona Lisa are there, so if you introduce a light source, Mona Lisa will appear again, because the same causes that made the image appear before are repeated.