Thursday, January 07, 2010

Not Even Remotely Scientific Behaviour !

'whether it ought to be conceded that the Holy Spirit could be increased in man [that is] whether more or less [of it] could be had or given’

Peter Lombard

'For whether it commences from zero degree or from some [finite] degree, every latitude, as long as it is terminated at some finite degree, and as long as it is acquired or lost uniformly, will correspond to its mean degree [of velocity]. Thus the moving body, acquiring or losing this latitude uniformly during some assigned period of time, will traverse a distance exactly equal to what it would traverse in an equal period of time if it were moved uniformly at its mean degree [of velocity].'

William of Heytesbury

I was amused to see Richard Carrier’s horrified reaction to the suggestion that Thierry of Chartres’s commentary on Genesis had anything to do with science. For Carrier, Thierry’s effort - which attempted to set out the creation of the world using Platonism and Aristotelian logic‘isn't even remotely scientific behaviour’ and ‘almost in every way exactly the opposite of doing science’. In fact it is so the antithesis of science it even confirms Jim ‘no beliefs’ Walker’s graph of ‘scientific advancement’ which depicts the Christians of the early to high Middle Ages as a bunch of indolent, sub-literate, bible bashers.

This is to miss the point by a couple of million light years. What we recognise today as modern science did not exist in antiquity and the Middle Ages. What did exist were inherited beliefs about nature; theories concerning the origins and structure of the cosmos; speculations about the motions of celestial bodies, the nature of elements, diseases and health and explanations of natural phenomena. These were the ingredients which would eventually develop into modern science.

Furthermore, the natural philosophers of this period were not like modern scientists, though we are often guilty of projecting our worldview onto theirs. Their explanation of the natural world was inseparable from their philosophical views, their religious beliefs and their theological assumptions. The full historical picture is therefore highly complex because science, philosophy and theology are so inextricably entwined. If we want to understand it, we can’t simply go back through the past giving ‘gold stars’ to those who conform to our expectations and red lining those who don’t. It is true that if you submitted Thierry of Chartres's Hexameral treatise to the scientific journal ‘Nature’ today it would doubtless be dismissed as ‘hand-waving’ and ‘kookery’; but in the context of the early Middle Ages these commentaries provided a framework and a context in which natural philosophy could be done and they undeniably furthered the study of the natural world.

Another good example from the Middle Ages is what we would today recognise as the science of the kinematics (dynamics, or causes) of motion. As documented by Edward Grant in ‘The Foundations of Modern Science in the Middle Ages’, this actually seems to have developed out of a purely theological speculation made a couple of centuries earlier. In the middle of the Twelfth century, the theologian Peter Lombard asked a question about how grace or charity could be increased in a person. Could a person become more filled with grace or more charitable?, or as Peter put it ‘whether it ought to be conceded that the Holy Spirit could be incread in man [that is] whether more or less [of it] could be had or given’. His answer was that, since grace and charity are gifts of the Holy Spirit, they are absolute quantities and cannot vary. This means that when a person becomes more charitable it is only because of his participation in absolute charity.

All theologians who wanted to get a degree in theology had to write a commentary on Peter Lombard 'Sentences' and this meant addressing this question. One commentary posed an alternate answer which disagreed with Peter Lombard’s original conclusion, one proposed by the Franciscan theologian John Duns Scotus (John the Scot; Scot in this case meaning Irishman). Scotus was born around 1265 and died in 1308. His argument was that charity could be added incrementally; in fact every quality in a person could be added or diminished incrementally. This idea would come to be known as the notion of the intention and remission of quality. After this was proposed it came to be applied to Aristotelian notions of quality, but also to motions of place.

Aristotle had said that there were three kinds of motion. Motion of place, from point A to point B. Motion of quantity, when the quantity of something changes; and motion of quality, for example when an apple turns from green to red. Once the notion of intention and remission had been applied to notions of quality (the amount of grace or charity in a person) it could also be applied to motions of place; or in other words an object moving from a to b or moving with increasing speed. This meant that speed could count as a ‘quality’ and we can therefore add speed with conceptual validity. As time went on, the scholastics who debated this point became less and less interested in the theological and ontological aspects and more interested in the mathematical aspects of qualitative change.

In 1330 a group we have touched on before called the Oxford calculators began to use the intention of remission of qualities to talk about local motion. Three of these are William of Heytesbury (who according to Carrier, failed to ‘[advance] the sciences in any important way’ so best not bother reading about him), John Dumbleton and Richard Swineshead. These were all scholars at Merton College Oxford. They defined for the first time, notions of uniform velocity, uniform acceleration and they tried to get a handle on the notion of instantaneous velocity (velocity at one given instant during an acceleration. Uniform velocity was defined as the traversal of equal distances and equal instances of time and that uniform acceleration was the addition of equal increments of velocity added in equal intervals of time. This is pretty much the modern definition, except expressed in a slightly different way.

They also devised the mean speed theorem (which according to Carrier’s definition is a ‘renaissance’ invention; and in any case, it wasn’t used properly until the scientific revolution when some Gibbon-eque ‘scientific values’ mysteriously permeated society and ousted the faithheads; in any case Archimedes probably came up with it, we just don’t have the evidence yet and arguments from silence are invalid etc etc..).

The mean speed theorem goes something like this. Assuming that there is uniformly accelerating motion (a body going from zero to say 60 miles an hour) a body will travel the same distance in the same time as another body moving at a constant velocity which is the mean between the starting velocity and the final velocity of the first object. In other words, if we have an object that is starting at a speed of zero and it goes to a speed of eight, it will traverse in a given interval of time in the same space as a body moving with a velocity the mean between zero and eight (four). William of Heytesbury’s version from ‘Rules for solving sophisms’ goes as follows:

“For whether it commences from zero degree or from some [finite] degree, every latitude, as long as it is terminated at some finite degree, and as long as it is acquired or lost uniformly, will correspond to its mean degree [of velocity]. Thus the moving body, acquiring or losing this latitude uniformly during some assigned period of time, will traverse a distance exactly equal to what it would traverse in an equal period of time if it were moved uniformly at its mean degree [of velocity].”

Why is this at all important? Firstly this set the foundations for kinematic motion. The truth of the mean speed theorem was proven geometrically by (among others in the fourteenth and fifteenth centuries) Nicole Oresme in 1350 and Oresme’s proof, which appeared in ‘On the Configurations of Qualities and Motions’, was well known thereafter. This was significant because as God’s Philosopher’s shows, Oresme’s proof of the mean speed theorem appeared 300 years later in 1638 as the fundamental axiom of the new science of motion in Galileo’s ‘Two New Sciences’. Part of Galileo’s work is therefore rooted in the work of the Oxford Calculators, who in turn were dependent upon the result of an obscure theological question, first propounded by a ‘woo merchant’ called Peter Lombard in the middle of the twelfth century. This example shows us how enormously far a succession of ideas can move and develop from their original source. An enquiry about the nature of the Holy Spirit, grace and charity eventually contributed to a fundamental axiom of kinematics.

We therefore need to take an extremely wide view when reading the history of science. You cannot simply go through intellectual history, isolating things we recognise as scientific. If you do that, you completely miss the historical context and the causation behind things. You miss an enormous amount of the influences that come in and originate from what we would today segregate as non scientific activity. Sure, it might be 'not even remotely scientific behaviour'; but so what?; appearances can be deceptive.


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