Since writing the original essay I have had a very interesting response which has lead on to further discussion of this topic

"If the simple cause and effect universe (everything decided at the time of the Big Bang) is unlikely because of probabilistic quantum effects, then that would suggest that there is only a probability that we will do anything ie: human actions are driven only by a combination of automatic, instinctive responses and probability. I am not convinced that this is the same as free will - its a bit like saying a dice has free will because it we can't predict which number will come up next. If free will does exist (and I am not entirely sure exactly how one might define free will), then there must be some mechanism for influencing that probability (ie, a "loading" mechanism for the dice, so that if we want to, we can generally make it come up "3" say). If the mechanism is based on normal atoms and other quantum particles (which operate in a probabilistic way), then it seems to me we have gone full circle. If the free will mechanism is something else (ie: not based on quantum mechanics), then we are moving into a completely unknown area."

Obviously an excellent point and well made. My theory has a fundamental flaw - the weakening of the relationship between cause and effect does not allow for free-will all of its own. Dave's response is below:

Last night [20-JAN-04] I went to a lecture / discussion on quantum physics at the RI. The lecture bit was interesting, but all standard stuff. However the questions from the (seemingly very learned) audience were fascinating.

One guy specifically asked whether it was the randomness of quantum physics that allowed us to state that our mental states were not pre-determined. The speakers were of the opinion that this could be the case. In another question they also highlighted that quantum effects had been detected (in the manner of the two slits experiment) in large molecules (i.e. micron scale which means fine for biological molecules) and that researchers were now examining viruses!

At this point I was of course bursting to ask your question, but was unable to because of the volume of other people. However I did manage to talk with the guy who had asked the fate question afterwards. I put your question to him, but he said that he did believe in determinism of the mental and asked me to justify my belief that it was bad that mental states might be pre-determined! This rather sideswiped me, but we had an interesting discussion on one of the points during the lecture:

Basically it seems that there is a debate between quantum physicists. Some believe (as Bohr) that the theory is only epistemic in its application - that it only defines the boundaries of what we can know - and as such can be seen as a conceptual framework for our understanding of actuality. Others (as Bone) believe that the theory is ontological and is a literal description of reality.

The speakers rejected the approach of Bohr by referring to experiments that apparently prove such quantum effects as being in two places or states at once. One of the speakers also said that Bohr's approach lead to solipsism, although I'm not sure of his reasoning here. Needless to say there wasn't time for them to expand upon these points, but it seems that the accepted view is that quantum mechanics does describe reality.

This leaves us with the problem of whether quantum mechanics affects our mental processes. In terms of Heisenburg's uncertainty principle it seems that the wave function that describes the probability distribution of the location / momentum of a particle is more certain at shorter time scales. This does not preclude randomness, but apparently "quantum weirdness dissipates from a point over time in the same way as heat dissipates from a point". Thus if we have a 90% chance of our particle being at a certain location at time t+0.01 then this will have reduced by time t+0.02.

This also highlights the issue of scale: essentially as the dimensions of the system increase the less effect the tiny quantum fluctuations will have on the system. It is possible that although mental processes at the molecular scale will 'feel' quantum effects that these effects will be minor.

My assumption in my essay that a very complex system (such as consciousness) might be affected by very small influences (and thus potentially quantum effects) could be wrong. I'm hoping to learn a lot more about complexity theory in my OU systems course, which starts soon, this may lead our debate further on!

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