For if that which is done away was glorious, much more that which remaineth is glorious

Friday, 1 November 2013

Why Science Needs Plato Baptised: Part 1, The Myths of Science


What follows is the groundwork for a second post that I hope to write soon: this is Part 1. Part 2 is an attack upon the Aristotelian notion of science. This is not because I think it is nonsense, but because I think it needs a Platonic foundation to make sense. (This might be a Part 3, I’m not sure yet. Let’s see how I get on.)

There are a few odd scientific myths around – at least I think they are myths and would be interested to hear what other people have to say – about “accurate” measurements and the notion of measure in general. When I talk about myths of science, I mean the popular version that leaks out – even from scientists – into public consciousness, whatever caveats are added in academia. I can give three examples of what I am talking about.

1)      Time: we are told that the Earth’s rotation is slowing down, meaning that the solar day is getting slightly longer and a leap second has to be inserted at various intervals. But the Earth is getting slower in comparison to what? To the atomic clock – which measures time very accurately indeed, deriving it from the frequency of radiation emitted when an electron moves from one energy level to another of a caesium-133 atom. But apparently colder atoms move more slowly, so the time measurements also need to be standardised by cooling caesium-133 to almost absolute zero.

2)      Space: a metre started out as one ten-millionth of the distance between the North Pole and the Equator proposed in 1790 by the French Academy of Sciences after the Revolution as the basic unit of measurement. Because of a miscalculation (they reckoned on the Earth being perfectly spherical which, as they discovered in 1793, it isn’t) it is about 0.2mm short. Then, in 1889 the first “General Conference on Weights and Measures”, Conférence Générale des Poids et Mesures, came up with the notion of having a prototype platinum bar made as a standard – it is still locked up somewhere – but of course the measurements have to be taken at a certain temperature (viz. the melting point of ice) because the bar expands a little with heat. There are other problems with the accuracy of this bar as a standard, too, and so in 1993 the standard definition was changed to something more accurate still: and the metre is now defined as the length of the path travelled by light in vacuum during a time interval of 1/299,792,458 of a second.

3)      Properties: we are told that certain colours correspond to certain frequencies of light on the visible part of the electromagnetic spectrum. But, in fact – and as every child who has pored over an optical illusion knows – how one sees a colour depends on the colours around it. So what is really (according to measured frequency) a certain shade of green looks, in certain conditions, a lighter shade compared to exactly the same frequency of green light in subtly different conditions of light.

Now for what I see as mythical about (1), (2) and (3) in the sense that people have so accepted a “scientific” version of these phenomena that they have stopped thinking about the most basic premises of the thinking involved.

(1)   Involves the idea that (ultimately) seconds are gradually getting a bit longer. But this is a rather perverse notion when one thinks about it. We decide the length of a day (a “solar” day as the scientists have it) by measuring midday to midday: crudely put, by the time it takes between the shadows being at their shortest on one day, to the shadows being shortest on the next. If one then divides this period into 24 hours, and then divides the hours into minutes and seconds, one eventually has the “length” of a second. But it therefore stands to reason that there is really no other reference for the length of a second than the ratio of 1/86,400 to the length of a solar day. Just say that one picks, at random, today (which happens to be All Hallows’ in the year of our Lord 2013) and fixes on the length of the second at midday and sets this up as the absolute standard, one could then measure whether (relative to this arbitrary standard) the days are getting shorter or longer over time. But this raises another problem. One must then find some other way of fixing the exact length of the second, some reference to say this and exactly this is the length of our new standard second. Hence the need for the atomic clock as mentioned above.

But this raises yet another problem, and therefore another question. One then assumes, as the basis of all comparison for all temporal measurement, that the atomic clock is striking out a fixed and unchanging time period: that it doesn’t slow down or speed up. Now it might be part of one’s scientific theory that the atomic clock is indeed ticking along immutably at one standard second per second: but the problem is that, even if it did change, one wouldn’t know, because one has nothing to compare it too. There are three questions raised by this problem. (a) First, why advance the atomic clock as the absolute authoritative time, when it is obvious that all time must be measured as a comparison, and therefore in ratio, to something else? There neither is, nor can there be, such a thing as an absolute time measurement. All measurement of time involves a comparison or ratio (made by us) of one phenomenon with another e.g. the high point of the sun in the sky to measure a solar day. My objection isn’t to the use of an atomic clock for some purposes, but to point out that the notion of absolute time is a scientific myth. (b) And secondly, what is the rationale for the choice of one particular length of second as the “standard second” when – according to the atomic clock – no one second is the same length? Isn’t it just arbitrary? (c) And thirdly, why say that seconds are getting longer when they are, in the first place, a division of the solar day into 86,400 bits?

My points can be summed up as follows – we have a mythical notion of absolute time, when time is in fact always a comparison of phenomena made by us, and we have created a strange situation where we have so lost touch with the idea of what a second is, that we have set up a “standard” second whose length bears no present relation to the actual temporal phenomena of a second. Not only have we allowed science to set up an absolute standard where there can be none, but we have redefined the word “second” to mean something that doesn’t fit with what a second actually is, i.e. a small division of the solar day.

(2)   The objections canvassed above will give the flavour of what I am going to say about the measurement of space: again, there is and can be no absolute standard, because like time it involves a comparison, made by us, between phenomena, and the use of ratio. A platinum bar in a vault can never be an absolute standard, because it is measured against something else, which in turn must be measured against something else: and, to prevent the inevitable ad infinitum conclusion, one is driven to choosing something somewhere as the absolute standard, with all the problems and questions that that raises. This is exactly what has been done in the measurement of space. When one tries to fix time or space measurements, one finds that everything is altered by variables of heat, and every other kind of condition: so one gets right down to the most basic level of matter and energy that (in modern scientific theory) are the productive of all the other kinds of energy. And down at this level, one cannot measure time or space independently. [Here I must jump over a massive bit of modern physics to explain why one can’t.] By choosing the distance travelled by light in a certain time in a vacuum to standardise the measurement of distance, one introduces into the problem of distance measurement exactly the same collection of problems and questions mentioned above in (1) with regard to the measurement of time.

(3)   My final set of objections, about properties, is anticipated in what I have already mentioned about time and space. We observe a colour, for example: we then invent a scientific theory about the frequency of light to explain why colours are the colour they are. Subsequently, we discover that in certain conditions, what looked red looks more like purple, and because the measured frequency of light is still what we expect red to be, we then say that our eyes are in error. The colour is actually red, and our seeing purple is a mistake. But surely we cannot use a scientific theory to trump the very phenomenal observations on which the theory claims to be built in the first place? The myth here is that science tells us what e.g. colour really is – even though colours are simply observed phenomena, not measured frequencies of electromagnetic radiation.

There is, I think, something not quite right here - Part 2 will try to say why things are going wrong, and Aristotle will get some of the blame.

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