Re: causality and will

Hal Finney (
Mon, 3 Feb 1997 09:40:47 -0800

From: Lyle Burkhead <>
> As long as macroscopic events are the result of atomic motions,
> it doesn't matter whether atomic motions are deterministic or not.
> [...]
> (b) Suppose they are not: atoms (sometimes) move discontinuously
> and unpredictably, and the result of all such motions is the world
> we experience.

I am still trying to understand Omega's notion of "acausal" actions, which
he seems to distinguish from both randomness and determinism. An acausal
event is one which has no cause, yet is not (simply) random. Does this
make sense? Can we really distinguish acausality from randomness?

It also seems true that, since the brain is composed of atoms and its
activities can be looked at as the activities of its atoms, if the brain
can be acausal then presumably at least some of the activities of its
atoms are acausal. So this cannot be a concept which applies only to
conscious actors, but it must apply at the microscopic scale as well.

An acausal event is not determined by other events, but it is not random,
either. What could this mean? Well, when we think of randomness, we
think of probability. In principle with a random event we can specify
a probability distribution over its possible outcomes. Then we can
imagine executing the event multiple times and observing the outcomes
to see what the probabilities are.

This requires a counterfactual perspective. We have to imagine what might
have happened if we had turned back the clock and redone the random event.
(Alternatively, we could imagine preparing an ensemble of systems in
identical states and observing the probability distribution over the
outcomes of the many systems.)

Perhaps one way to distinguish an acausal event from a merely random one,
then, would be to deny this counterfactual possibility. We would have to
stipulate that acausal events, by their very nature, cannot be re-done in
the manner that would be needed to establish a probability distribution.
Since in fact we cannot turn back the clock, this is not in itself a
very great leap.

For the case of the ensemble of identical systems, we would have
to specify that this is impossible in the case of acausal systems.
Perhaps there is something about their state which makes it impossible
to (ever) have multiple systems in the same state (obviously I am going
beyond conventional physics here; this is philosophy). Any acausal
system occupies a given state only once in the history of the universe.
It acts, undetermined by events, and goes on. There is no possibility
for a statistical evaluation of its random probability distribution
because there is only one event, hence no statistics, hence no probability
distribution and arguably no randomness.

This can provide a counter to the argument that acausality is not a
comforting source of free will because it is "just random", like tosses
of a coin. Coin tosses and other familiar sources of randomness can
be repeatedly executed and a probability distribution established.
Any given execution involves choosing an outcome blindly based on
the probabilities. But acausality is different because there are no
probabilities. The outcome is chosen as part of an irreproducable event.
In effect, acausality is by definition outside of scientific analysis
because there is no possibility of replication and testing. This is
very different from our conventional notion of randomness and so our
intuitive abhorence of such effects as the source of our actions should
not apply in this case.

Well, that's the best I can do to try to understand what acausality
might be. It is difficult to find this tiny crack in the conceptual
boundary between determinism and randomness, but I am not sure we can
deny its existence.