Hi Glenn,
I agree that physics is compatible with idealism if by
idealism you mean the sort of approach Leibniz uses. He is often called an
idealist, but he makes it clear that there is a real universe of goings on that
is distinct from the point of view that is the subject/monad, even if that
universe is ‘reflected within’ the monad. Bascially, it is not an idealism that
says that there is no mind-independent reality. Even for the monad much of the
real universe is only perceived in a totally confused and indeterminate way,
but it is still ‘out there’ in infinite detail. Put another way all goings on
are reflected in all other goings on, if confusedly and do not belong to and
are not created by any particular observer observing.
So if idealism just means that everything is ‘mental’
that is fine, except that if we want to have useful descriptions of the
interactions between such ‘mental’ entities the best system we have is physics
so it is unclear what is gained by calling events ‘mental’. Dynamism is the neutral
position of saying that all we presuppose are the dynamic relations, without
committing to calling things mental or physical. It is the only approach
consistent with physics in the sense that it denies any additional token
quiddities.
I certainly do not assume that we are in a universe
that ‘contains a form in spacetime’. That is thing-ism again. In Leibniz’s terms
space and time are abstractions from the quantitative aspect of dynamic
relations. This was his big argument with Newton. There are no things in
anywhere. So no, I am not making those metaphysical assumptions.
A block universe that is somehow ‘static’ or
‘unchanging’ is a metaphor that shifts 4D Minkowski space into a language of 3D
space (fudged to 4D even though nobody can do that) without time – asking one
to imagine a block sitting there. It is thing-ist again. The block universe
does change because change is what you get with time and Minkowski spacetime
has time in it. It is just playing around with envisagings of metaphysical problems
when we know envisaging can only confuse. Space and time are not ‘like
anything’ except in the sense that they are like what they are like to us in
ordinary experience. So questions like ‘has the future really already happened’
are just meaningless.
With regard to what my field variables would be
representing I don’t think they represent anything. They are dynamic field
variables. They are the pattern of the relation. There are no ‘things’ that they
represent.
Fifty years ago as a teenager I arrived at a metaphysical
framework that I called electrical point consciousness. I ascribed sentience to
every point in the universal EM field. This is in fact what Leibniz did in his
youth (around 1670). However, on returning to the problem forty years later I
realized that a point in spacetime is no good because it has no dynamic power
of its own – it is just a place – and in fact because of Heisenberg uncertainty
there may be no real infinitesimal points. Leibniz seems to have realized
something similar and shifted from a’physical point’ to a ‘metaphysical point’.
A metaphysical point is not one point in space but rather one dynamic
individual. It has a point of view but that is not from a point but from an
‘aspect’ that is focused on a domain that is its ‘body’ but continues out to
include the whole universe. This is exactly what we see in a quantum wave
equation. We have a V term that has no boundaries and therefore covers
potentials in the whole universe, but values for V only affect the solution to
the equation non-trivially in a local domain often called a ‘wave-packet’. For
the modes of excitation that occupy ordered bits of matter the analogy with
Leibniz is particularly striking because the values for V for an acoustic mode
are tied very tightly to the domain of that bit of matter. Thus if there is
piezoelectric coupling the photon field to which a phonon is coupled is
tightly restricted to the ‘body’ that vibrates.
In other words, like Leibniz I am not cutting out a
segment arbitrarily. I am giving the subject a special relation in a domain
defined by the wave equation but a notional relation to everything else as
well. Also we are not talking of thing-ist content of spacetime but always of
relation to a mode. Each ‘I’ is a different mode. Since our brains are not
overlapping there will be very little overlap in the domain of non-trivial
influence on a ‘you’ and a ‘me’. But of course if we were talking of robots we
could probably construct one in which the field of potentials influencing two
subjects overlapped.
Yes, I think it unlikely that any human subject, in
the form of a mode, lasts more than a few milliseconds. However, there is
something very odd about acoustic modes here which relates to their being Bose
modes with a wide range of possible energy contents (i.e. with a wide range of
possible quantum number for the notional ‘number of particles’). This is where
it is very hard to read the metaphysical implications and it might be that we
can legitimately treat a neuron as an enduring subject over many years.
If you experience typing on a computer my suggestion
is that a neuron gets an input of potentials that have a pattern that usefully indicates typing on a computer. The neuron could be in a vat, as long as
someone plugs in synaptic boutons that will fire the right pattern of signals. Whether in that situation the pattern would be 'useful' is doubtful but that seems obvious, and an unrelated question. This is why I think functionalism is a dead end. It gets tied up in issues of broad and
narrow content and Putnam’s confusions about externalism which arise purely
from philosphers not taking care with their words. Before discussing things like
RoboMary one has to be very clear what one is meaning by reference and meaning
etc etc and to be aware of the ascertainment problems that cloud all statements
about what experiences are like.
The weasel words in David Chalmers functionalist
account are ‘of sufficiently fine grain’. If function is dynamic relation then
to get the right experience you would need the right relations – and presumably
down to the finest grain there is to get it absolutely right. That ends up with
an identity theory that no longer needs to be called functionalism. I cannot
see any conceivable reason why events in silicon chips should seem to some mode
within anything like what they feel like to modes in neurons, even if one was
allowed to make such a comparison. Apart from anything else inputs to the electron modes that support semiconductivity in a computer would only seem to have two relevant degrees of freedom, instead of 40,000 in a neuron.