As a Western scientist, here are the questions that I would ask the most accomplished Buddhists (i.e., Arahants, Bodhisattvas, or Buddhas) about mindstreams and self-other mental construction:
- Can we identify substances that act as substrates/support for mental phenomena, as well as their properties, how they nourish/support minds, and the ways in which certain mental phenomena can emerge from, or be encoded/preserved upon, certain substrates?
- Is nirvana a more stable substrate for the mind?
- Why is the mind radiant? Are mental phenomena encoded on some kind of light?
- How cohesive and stable is a mindstream? Does it degrade, when the body is old or unhealthy? Between lives, can mindstreams split (like light) or fade/degrade (like radio waves), if they are not reborn quickly enough?
- Could we develop signatures/fingerprints (like a hash function) for specific mental phenomena or for an individual’s mindstream, and track those phenomena’s movement through and between different substrates/lives?
- Can the karmic seed-to-fruit metaphor be demonstrated under well-controlled (i.e., laboratory) conditions? How exact/one-for-one/fair is karmic retribution, and do any other forces intervene (e.g., the natural environment, genetics, the actions of other beings, etc.)?
- Can we compare the mental and substrate phenomena of different species with our own?
- If everything we see and think is a construct, are there methods of consciously controlling the constructions? For example, could I consciously construct the perception/vision of an apple sitting on a table, or of another person in the room with me, when there is not really one there (i.e., a waking lucid dream)?