Ruling hypotheses and invented evidence

Standing stone and recumbent stone at Waun Mawn.  But why should these stones be thought to have anything whatsoever to do with Stonehenge?  Is that the most preposterous hypothesis ever dreamt up by the quarrying archaeologists?

Thanks to Chris for sending through a small published booklet (67 pp) entitled "Science and Stonehenge" by Prof Mike Parker Pearson.  It appears to have been published in the Netherlands on 2nd March, in association with a lecture given at the Netherlands Museum of Anthropology and Prehistory.  It's not clear whether the text is a word-for-word version of the lecture given, or  a "background document" presented to attendees.  Anyway, it purports to summarise the giant leaps forward in the use of scientific techniques in studies of the old monument and its environs.  It all sounds impressive indeed,  but here's a question:  should the lecture have been entitled "Technology and Stonehenge"?

There is a huge difference between technology / techniques and true science, and I'm not at all sure whether archaeologists understand what that difference is.  I seem to recall that somewhere or other, not so long ago, MPP argued that archaeology is not a science, and that archaeologists could operate free of scientific constraints; but here he seems to be arguing that archaeology (at least at Stonehenge) is very scientific indeed......

Anyway, there is much of interest in this small publication, and it's a useful summary of the state of play relating to dated phases of occupation and construction.  The conclusion -- on "Explaining Stonehenge" -- is intriguing, and will be worth discussing on another occasion.  But what interests me right now is the issue of the scientific method.  Let's assume (for the sake of argument) that MPP truly represents current British archaeological opinion in this article, and is not just promoting his own ideas.......  Let's also ignore for the moment the standard denial that there is any dispute over the long-distance human transport of bluestones or the Neolithic quarrying of bluestones from sites north of the Preseli Hills.   That denial is in itself unscientific, but we'll let that pass too.

ON SCIENTIFIC HYPOTHESES

On the second page of the document there is this very intriguing statement:  "At the core of recent scientific enquiry into Stonehenge is the application of a hypothesis-testing approach".  Linked with this is the proclivity to predict things, based upon the assumption that the relevant hypothesis is a reliable one. If this is the approach of method that drives British archaeology at the moment, I hope that there are some people out there who are concerned about it, and who are asking questions about there hypotheses come from, and how they should be used.

Here is a short statement on hypotheses from "Live Science"

A scientific hypothesis is the initial building block in the scientific method. Many describe it as an "educated guess," based on prior knowledge and observation. While this is true, the definition can be expanded. A hypothesis also includes an explanation of why the guess may be correct, according to National Science Teachers Association.

Hypothesis basics:     A hypothesis is a suggested solution for an unexplained occurrence that does not fit into current accepted scientific theory. The basic idea of a hypothesis is that there is no pre-determined outcome. For a hypothesis to be termed a scientific hypothesis, it has to be something that can be supported or refuted through carefully crafted experimentation or observation. This is called falsifiability and testability, an idea that was advanced in the mid-20th century a British philosopher named Karl Popper, according to the Encyclopedia Britannica.

As anybody with a scientific background will know, hypotheses cannot simply be conjured out of thin air -- on the contrary, they have to be based on prior knowledge or observation.  Those who propose hypotheses are required to demonstrate and explain to others that there is already hard evidence suggesting that the hypothesis is reliable.  If you can't do that, you are in grave danger of being carved up by Hitchens's Razor, and nobody will take you seriously.  There must be no predetermined outcome in the testing of the hypothesis, and you must always be open to the possibility that your hypothesis will be proved false.  As I have said many times on this blog, there is a world of difference between a working hypothesis and a ruling hypotheses.  If you adopt a ruling hypothesis and devote your life to showing the correctness of it, you have a problem.  The probability of being proved wrong is increased, and you place your reputation seriously at risk.

As a research student, I learned that you start off with a problem or an academic dispute, collect evidence that appears to be relevant , work out what that evidence appears to be telling you,  formulate your working hypothesis, test your hypothesis against further collected evidence, and finally either falsify it or modify it according to what you have found.  In a research thesis situation, your lines of reasoning and your presented evidence will be scrutinized by two or more rather hostile individuals who may or may not award you a doctorate of PHILOSOPHY.    That's interesting in itself -- I'm a doctor of philosophy and not a doctor of geomorphology.

The key to good practice and good research is patience -- you must not introduce your hypothesis too early.  If you wait a bit, until you have a reasonable amount of accumulated data, it is much more likely to be correct or almost correct.

On that basis, let's take a look at a few hypotheses, and ask ourselves how reliable they may be.

1.  Most of the bluestones at Stonehenge came from north Pembrokeshire.  That hypothesis, introduced by HH Thomas in 1922,  is a reliable and perfectly valid one, since it was based both upon field observations of rock types by various geologists and upon laboratory work on the petrography of rock samples from Pembrokeshire and Stonehenge by Thomas himself.  No matter what the shortcomings of Thomas's work were, the broad correctness of it has been confirmed by much subsequent work by many other geologists, using  a wide range of other techniques.  

2.  Most of the bluestones from Pembrokeshire sources were carried by glacier ice towards Salisbury Plain.  That is a reasonable working hypothesis, because it is based on the abraded and weathered nature of  the bluestones at Stonehenge, on well-established directions of ice movement as worked out by many field researchers over the years, and on the presence of glacial deposits in Somerset and on other Bristol Channel coasts. The evidence is not conclusive, but it is suggestive enough for the hypothesis to be considered seriously.

3.  The bluestones from Pembrokeshire were carried by Neolithic tribesmen from their source area all the way to Stonehenge.  That is an unreliable hypothesis since there is no evidence on the ground in support of it.  Neither is there any evidence from anywhere else in the British Isles to suggest that the "bluestone expeditions" might have happened.  The hypothesis is rendered even more unreliable because it is based upon the assumption that hypothesis number (2) cannot possibly be true.  The "human transport" hypothesis can, according to Hitchens's Razor, be rejected out of hand.

4.  There were Neolithic quarries in Pembrokeshire devoted to the winning of bluestone monoliths which ended up at Stonehenge.  This is an equally unreliable hypothesis since there is no supporting evidence on the ground that withstands scrutiny.  The Carn Meini "quarry" has been shown by the geologists not to have existed, since none of the spotted dolerite at Stonehenge matches the local rock type.  The supposed quarrying features at Rhosyfelin and Carn Goedog are also hotly disputed,  and are interpreted as entirely natural features, owing nothing to human intervention.  There are no unequivocal traces of quarrying activity, and the radiocarbon evidence does not support quarrying or the time frame proposed by the archaeologists.  The hypothesis can also be rejected out of hand. 

Two reasonable hypotheses, and two unreasonable ones. What is extraordinary about this article by Prof MPP is that the two unreasonable hypotheses are simply assumed to be correct, with no acknowledgement that the  evidence presented from the digs at Rhosyfelin and Carn Goedog is disputed in two peer-reviewed articles, and no acknowledgement of the fact that no evidence in support of long-distance human transport of the bluestones has ever been found.  The existence of reasonable hypothesis No (2), as noted above, is not even mentioned in this new text.  This is not sound science, and it is not sound archaeology either.


ON INVENTED EVIDENCE

On this blog we have expressed concerns, many times, about archaeologists being so keen -- or so desperate -- to find the evidence they need to support their unreliable hypotheses that they "see" evidence where others see nothing unnatural and even create archaeological artifices which are then flagged up as important pieces of evidence.  We can judge for ourselves whether these artifices are created deliberately or unconsciously.  If the latter, we can express sadness about the over-enthusiasm and perhaps the naivety of the field workers involved;  if the former, we are into the territory of scientific malpractice.

In past posts, we have looked at evidence "invented" by Professors Darvill and Wainwright with respect to the features seen in the Carn Meini and Talfynydd area.

Then we had the labelling of all sorts of natural features at Rhosyfelin and  Carn Goedog with "engineering" terms.  Now we have another example.  In this latest publication Mike Parker Pearson confirms the name and the purpose of the latest project involving his team:  "We are currently engaged in a fifth project, the Origins of Stonehenge,  exploring what we believe to be the stone circle in Wales from which the stones of Stonehenge's first stage were taken." (p 8)    Then, on page 21, he says this:  "This perpetual re-positioning of bluestones may not have been confined to their time on Salisbury Plain, since there is evidence that they may have formed a stone circle in the Preseli hills of West Wales."

Sorry to be brutal, but there is not a shred of evidence to support that statement.  There may be slight evidence of a stone circle on Waun Mawn, but there is nothing at that site to suggest that it had anything whatsoever to do with Stonehenge.  The only reason for the increasingly wild speculation about Stonehenge is the mismatch between the radiocarbon dates from Carn Goedog and Rhosyfelin with the assumed or desired dates of quarrying activity.  So, the story goes, since the bluestone monoliths cannot possibly have been entrained and transported by the Irish Sea Glacier, they must have been quarried by Neolithic tribesmen.  What is more, they must have been quarried earlier than expected, and they must then have been parked somewhere else before being carted off to Salisbury Plain. This is not science.  This is fantastical storytelling on an ever more extravagant scale.

Why does the archaeological community put up with it?  Answers on a postcard please.....