An Expedient Mind: PROBABILITY and DETERMINISM

AN EXPEDIENT MIND

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PROBABILITY AND DETERMINISM

Probability
Tip a lorry load of sand on to the ground. It is very likely that the result will be a roughly conical heap of sand. I don't suppose that anyone would be likely to regard that event, as a miracle. Now take a magnifying glass and position yourself, without disturbing the heap, to examine the topmost grain of sand in that pile. If you had marked that grain of sand in some way, with a tiny blob of paint perhaps, and had done so before the heap was tipped from the lorry, then I think you would regard the appearance of that particular grain right at the top of the heap, as an extremely unlikely event.
It is exactly the same heap of sand. So what made the difference between a very ordinary event and a miracle? It was your prior expectation of that particular result. By doing so you singled out one particular result from a multitude of alternative arrangements. You could have gone further. If you had marked every single grain in the heap, and marked also the various facets on each grain, it is theoretically possible (although hardly practical) that you could identify every single possible arrangement of grains, plus the disposition of each grain. Whatever arrangement is the result of the tipping process is then incredibly unlikely. And yet some arrangment must happen. So does that mean that a miracle must happen every time a heap of sand is tipped from a lorry?

The Need for Prior Expectation
Clearly, something is missing from the calculation of probability which attends each tipping. The thing that is missing, is prior expectation. There has to be some one who wants, or in some way expects, one particular result. Without that expectation, all results become indistinguishable and therefore unexceptional. When we calculate the probability of a particular outcome, what we are calculating is the prior expectation of that outcome.
We can do the calculation retrospectively. We can calculate the expectation which a person would (reasonably) have of a given result, prior to the event taking place. But there is no point at all, in doing the calculation if there was no such prior expectation.

The False Creationist Argument
In passing, we can note that that is exactly the mistake which creationists make when they calculate the probability of the universe being as it is, or the emergence of life, or the structure of DNA being what it is. They not only ignore the gradual evolutioinary processes which may be involved and which completely change the calculation of probability, but they also ignore the fact that by doing such a calculation at all, they are pre-supposing that someone or something had a prior expectation of that particular result. In other words, by doing the calculation they are pre-supposing the result which they are trying to prove - that there was a creator who intended the result to be as it is. Circular logic of that kind is a common feature of theological arguments. When someone believes something very strongly, it is very easy for that person to build their own belief into the foundations of an argument in a disguised form and as though it was an indisputable fact, without realising what they are doing.

Probability - A Definition
The probability of any given set of circumstances, is the reasonable prior expectation of the occurrence of those circumstances.

Determinism and Absolute Certainty
"Determinism" is the name given to any system or mechanism, if the outcome is absolutely certain, or pre-determined. Following from the comments on probability above, determinism corresponds to 100 percent certainty of outcome.

Objections
Many will dispute that claim. It is often argued that determinism is a feature of certain systems, and that the pre-determined outcome of the system can remain pre-determined, even if we do not have sufficinet information to be 100 percent confident about the result. This is a serious argument to which I will return shortly.

Chaos Theory
Chaos is the name given to the way certain systems behave. In popular terminology it is called "The Butterfly Effect". (eg: A butterfly flaps its wings in Bolivia and a hurrican happens in the Himalaya.) In some systems, small errors propagate more errors, which then grown into very significant and unpredictable variations in outcoome. It is also the case that when we measure the position and velocity of any physical object, there is always an error involved. That has to be the case because no matter how accurately we may measure these things, it is always possible to measure it more accurately. If that is the case there must always be a very very small discrepancy between the first measurement and the second more accurate one. And so on ad infinitum.
In chaotic systems, these very small errors will propagate larger ones, until the result becomes significantly different from expectations.

The Three Body problem
Consider the problem of calculating the trajectory of three billiard balls which impact "simultaneously" on one another. I use the word "simultaneously" with caution, because the measurement of time is subject to the same problems of micro-measurement as spatial measurements. Call the three balls X,Y and Z. Let us say that the balls do not really meet simultaneously, but that X impacts on Y a fraction of a second before it impacts on Z. In that case it will meet Z with a slightly different velocity and momentum than otherwise. The trajectory of Z will then be different from our calculations based on simultanoeus impact of all three. We also have to take into account the slight elasticity of the balls which has an effect on the outcome. Take a speed camera with a microscopic lens and observe the impact very accurately. Such measurements are always inaccurate to some degree. Did X meet Y first or was it X and Z which collided first? The uncertainty propagates and we again have a chaotic system which cannot be predicted over a certain length of time.
And now I can come back to that objection offered by the "determinists". Even if we do not know the exact location and velocity of every billiard ball these physical objects do have some precise location and exact velocity. So the result is pre-determined. It is just unfortunate that we cannot work out exactly what that outcome will be.

Quantum Mechanics
Go down in scale. We are not talking about billiard balls now. We are talking about the molecules of the air, or in fluid solutions. the simple model of these systems, has various physical objects (the molecules) leaping about and impacting on each other. In chemical solutions it is these impacts which trigger chemical reactions if the attitude of the molecules are fortuitous. Now think about quantum mechanics which operates at the level of sub-atomic particles. The reaction of chemicals is dependent upon the reactions of their electrons in orbit round the nuclei of each atom. We are also told that the behaviour of these electrons is genuinely random, with locations which are probabilistic. Radioactive atoms also disintegrate without apparent cause. In at least one version of quantum theory, these random events are genuinely and inherently random. It is not just a question of our inability to measure with sufficient accuracy. If that is the case then these random events will affect the outcome, and not even the atoms themselves would know what was going to happen. So I do not accept the objections raised by the determinists. The behaviour of this Universe is genuinely chaotic. That, I hasten to add, does not mean that it does not follow recognisable rules and has a limited degree of predictability.

Back to {REALITY}
I have a further objection to determinism as a concept. If we replace "reality" with {REALITY} as I have argued elsewhere that we should, then the distinction between the behaviour of the "real" system and our ability (or inability) to predict how it will operate, vanishes. The "real" system is the mechanism which operates in our private {REALITY}. And in {REALITY} there can never be absolute certainty. Determinism is a myth. Those who argue otherwise, and try to make a distinction between what we can observe (and expect) and what is "really" happening, are clining to a view of "reality" which is not sustainable. What we can observe is all there is that we can ever know about. And all there is to know about is all there in {REALITY}.

{REALITY}

Clockwork
Determinists are fond of using clockwork mechanism as example of a deterministic system. Because of the way it operates, with the escapement mechanism controlling the release of energy stored in the clock spring (or battery), the outcome of its behaviour is entirely predictable. Or is it? Try predicting the time which will be showing on the face of the clock when the spring runs down or the battery dies. And there is another factor which is often overlooked when this clockwork argument is presented. Clocks do not exist in a hermetically sealed vacuum. They exist in the world and are subject to all kinds of unexpected happenings. There might be an earthquake which knocks it off the mantlepiece. or a meteorite may come smashing down from outer space. Someone may hit the clock with a hammer or just change the position of the hands. To predict the outcome of the system you have ti take all these things into account. In effect you have to calculate the likely course of events for the entire Universe in order to predict the course of events for one small part of the Universe. And you cannot do that for the reasons I have outlined above.
I repeat - strict determinism is a myth.

See also POPPERS NIGHTMARE in the arguments section.

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