P2 requires support, and it's complex. It really should be broken
into manageable bits rather than presented as a tangle of assertions
and attempted conclusions.
Maybe
P2(abc) non-material, non-mechanistic, and personal entities do really exist
P3(abc) their essential natures are irreducible to matter, mechanism,
and impersonalism.
P4 (abc) Therefore not all empirical phenomena are explainable by
material, mechanistic and impersonal explanations
I put in the abc because it's three distinct claims around
(a) non-material, (b) non-mechanistic, and (c) personal, entities
> Why can't quantum theorists even begin to agree on the notion of what an
> "observer" is?
There is a degree of woo around that but it isn't that hard.
The observer does not need to be a conscious entity.
Observing requires that some energetic interaction take place.
Outside of energetic interactions, the full suite of potential
of waveforms is retained. After energetic interactions, certain
former probabilities are negated. I don't think it's much different
than noting that prior to events there's a probability distribution
and after and event the probability collapses to 1 or 0. That's
most of it but it gets played with.
> Why is there so much hostility exhibited by those who hold rigidly to P1
> whenever it is suggested that causality proceeds, not from the material
> to the apparently non-material, but the other way around?
I think you get hostility whenever you assert something that
you can't demonstrate. Especially when you keep asserting it and
stamping your foot and claiming that it is obvious.
> Why do so many hard-core materialists simply deny the existence of
> irreducible spirit as a primary component of reality, rather than take
> its existence as simply another an hypothesis to be tested?
Two good reasons, maybe others not so good.
The direct testing seems to be impossible. And regards an indirect
testing which involves asking "do we need something more", the answer
keeps coming up "no".
> These are not the actions of open-minded seekers of truth.
That's based on plenty of projected misunderstandings.
Back to your "logic". I might grant "personal" entities if I
knew what it actually means. People exist but they are material.
If you mean something like 'souls' then this currently lacks
objective support. I'm unsure about the others depending on
what we mean by exist. I'll grant that love exists in a conceptual
way but I don't grant that it is capable of impacting the physical
world. If someone you love dies, or stops loving you, I'm not so
sure that you have anyway to sense it. That said, there are some
powerful anecdotes that say otherwise. They intrigue me. I'd like
to believe that it was just a lot of confirmation bias in people
who were just worrying.
P3(abc) in my rewrite is more a matter of extracting defining
aspects of abc in preparation for concluding P4. But I wonder,
what does it mean to not be reducible. Does it mean that there's
no interaction between these things and what we can materially
measure, or that any interaction is so unpredictable that we
can't measure them? If there's no potential interaction then
science rightly ignores them. Most other answers seem to involve
a great deal of special pleading. But there's that referred claim
that they are empirical phenomena. In what way are they empirical?
If they can be measured, then at least that aspect by which they
can be measured can be reduced to matter and perhaps mechanism.
I'm not sure I grasp your intent with "impersonalism" other than
perhaps that the particulars who who is doing the measuring should
not matter.