Einstein’s often quoted out of context statement that God does not play dice with the universe, had no bearing on whether or not he believed God. It was no more than a rebuttal of Heisenberg’s Uncertainty Principle. This principle is one of the underlying assumptions of quantum mechanics. Basically it states that certain pairs of physical properties, such as position and momentum, cannot be simultaneously known to high precision. That is, the more precisely one property is measured and known, the less precisely the other can be known. This is not a failure of the researcher's ability to measure, but rather it is a statement about the system itself. In a system that is large, for example that which we can measure with a tape measure, this uncertainty is too small to be of consequence, but at an atomic level it is substantial relative to the size of the particles these measurements are applied to. Einstein never could accept this theory and attributed it to our present lack of knowledge and understanding. In a way he accused Heisenberg of making up a theory to fill the gaps in our knowledge, much the same as scientists will accuse religion of evoking God to explain whatever science is not able to come up with an answer to. So far the theory has held up.
Einstein was a bit old school in this; he wanted to keep the ideals of determinism in place. Everything has a cause and an effect and randomness is only apparent randomness. It only appears to be random because we do not have perfect knowledge of all the factors that caused the effect. Knock a cue ball into a triangle of billiard balls and the effect appears to be random. Not so, if you could plot the exact position and weight of each ball, the exact smoothness of the green baize, the exact air resistance, the exact direction and force that the cue ball strikes the first ball in the triangle, you could predict the exact position of all the balls on the table after all have ceased to move. It would take a fair bit of calculation, but with the right computer programme this should not be too difficult. Now extend the number of balls to a thousand and the table to a thousand square metres and fire the cue ball at a thousand miles an hour and you may find your computer programme could start to struggle.
The old Newtonian determinism was to view the universe as a clockwork mechanism, vastly more complex than a clock, but ultimately as predictable, provided perfect knowledge of all particles and forces therein are known. Of course from inside the universe such knowledge is not possible to possess, for practical as well as philosophical reasons. Determinism at the very least provides a deity with something to do, the super computer that knows the alpha and omega and all things in between. The need to determine a reason for existence does not exist, everything is already determined; the thoughts going through my mind at this instance were predicted a billion years ago. This universe has a certain fatalistic appeal to it, in a way it is comforting to know that we merely do what the script says; we are not really to blame for anything.
Quantum mechanics on the other hand points to a fundamentally different universe. Randomness rules at the core of it. If the attributes of particles are only knowable in terms of probabilities, then no matter how much computing power, earthly or ecclesiastical, you have at your disposal the present state can only tell you so much about the future or even about the past. Only probabilities are knowable and the further away from the present the less reliable any prediction becomes, and that is as true for the past as it is for the future.
This is of course very obvious; it is exactly how we actually experience the world. We didn’t really need Heisenberg to tell us that the universe is ruled by randomness. Our experience tells us that causality is only part of the story, we set off on a journey with defined objectives, but we come to the first fork in the road and causality gets diluted by chance. Only the young can believe in cosmic plans, life has a way of telling you that planning is just vanity. We play dice with our lives because we have no choice. The next move could be up a ladder or down a snake and it is more the product of chance than the wisdom of our choices. Naturally when it works out well we are less inclined to attribute our achievements to good fortune.
Without randomness life would not have arisen, much less intelligent life, evolution requires random mutations in the reproductive processes of life forms. Spin the clock back four billion years and re-run history and the chance that intelligent life (such as we call ourselves) will arise from apes to inhabit Earth at this time, is vanishingly small. There were too many chance twists and turns in the history of life, too many throws of the dice. If the God’s do anything it is evident to me that they are very fond of gambling.
I suspect we are all playing with a loaded dice, there may be an interesting debate around stochasticy and probability and the greyness in between causality and correlation and how they are often false positives or negatives of each other.
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