I have been interested in the idea of hierarchy of information and
where it comes from. Poincare is credited with the idea from the turn of
the last century. He used the term hierarchy of fact(1). Tracking down the
quote is a harmless pastime and is like identifying William Occam’s phrase
“entes non multiplicanda sunt praeter necessitatem”. Occam wrote some
years before computers, and in Latin and even I cannot bring myself to
wade through his Quodlibeta, which could be called the razor’s last hiding
place. Putting poincare and hierarchy through a search engine will score
many hits, but not the bit where he may say: “I have had this fantastic
idea…..hierarchies, hierarchies are going to really important in about a
century.” Really good ideas may not be known to be the really good ideas
at the time or perhaps he did not think it was that important. The
earliest I came across ‘hierarchies’ in a law report(2) is 1982. The
report concerned charitable status of a religious institution.
I have always thought that this concept of hierarchy when it is used
in the context of medicine, may be a busted flush. That is, the concept as
good as it is in pure maths, is not exportable. Suppose there is a
Scottish study that shows drug X to beneficial but there is then a larger
meta-analysis that shows X is not so good. Suppose further a Scot comes to
you with a diagnosis for which drug X could be used. Does one give the
drug (according to the Scottish study) or withhold it (according to the
meta-analysis)? The problem with ignoring the meta-analysis and treating
the Scot with drug X is that the hierarchy is inverted – and if one does
that, it is not a hierarchy.
This problem is less theoretical than may appear at first. In the albumin
study, although there was no overall benefit described in a much trumpeted
meta-analysis, there was a study of its use in children with meningococcal
septicaemia which showed a benefit(3). Readers were very keen to have the
opinion of the authors and anyone else who was in the news, such as the
editor(4) of the BMJ saying it was harmful, whether they would forbid its
use in their own children if the diagnosis were meningitis. The journals
did not ring with their cries of: “…and not even in my children!” In the
event, the silence of the great men was audible. The shakers shook not.
The leaders - didn’t.
A thought experiment such as the one above is called a gedanken
experiment and has a long history. Einstein used this a lot. Marie Curie
during a Solvay conference, records him lumbering around a foreshore
saying his most important task was to decide what happened when a ray of
light went through a free falling elevator. The earliest example of
thought experiment that springs to mind is Newton and the apple (a maid of
kent, I think) in the late seventeenth century.
In short, hierarchies may have a place in ordering information. The
issue is that a hierarchy is linear. If the information has more than one
dimension, then there will be more than one way to place them in a
hierarchy and not only that, the orderings may be inconsistent with each
other. The same evidence cannot simultaneously validate both of them. If
one is going to favour one way to order and reject the other why not
reject both and conclude the information cannot be validly ordered?
Priests never had this problem.
Hierarchies have a place in theory surrounding medical practice. They
may have a place near the centre, but I do not think that they are so
important that they should be placed anywhere near the top.
Oliver R Dearlove FRCA
Refs
1.D L Hurd JJ Kipling Origins and Growth of Physical Science, Penguin
Books 1964. Introduction
2. Valley Forge v Americans United 454 US 464 (page 15)
3 Levin M, Galassini R, De Munter C, Nadel S, Habibi P, Britto J, et
al. Improved survival in children admitted to intensive care with
meningococcal disease. Proceedings of the 2nd Annual Meeting of the Royal
College of Paediatrics and Child Health. York: Royal College of
Paediatrics and Child Health , 1998.
Conflict of interest: The author is a Council member of the Royal
College of Anaesthetists. These views are his own and do not represent
those of the Council (or his employer).
Rapid Response:
Do hierarchies exist?
I have been interested in the idea of hierarchy of information and
where it comes from. Poincare is credited with the idea from the turn of
the last century. He used the term hierarchy of fact(1). Tracking down the
quote is a harmless pastime and is like identifying William Occam’s phrase
“entes non multiplicanda sunt praeter necessitatem”. Occam wrote some
years before computers, and in Latin and even I cannot bring myself to
wade through his Quodlibeta, which could be called the razor’s last hiding
place. Putting poincare and hierarchy through a search engine will score
many hits, but not the bit where he may say: “I have had this fantastic
idea…..hierarchies, hierarchies are going to really important in about a
century.” Really good ideas may not be known to be the really good ideas
at the time or perhaps he did not think it was that important. The
earliest I came across ‘hierarchies’ in a law report(2) is 1982. The
report concerned charitable status of a religious institution.
I have always thought that this concept of hierarchy when it is used
in the context of medicine, may be a busted flush. That is, the concept as
good as it is in pure maths, is not exportable. Suppose there is a
Scottish study that shows drug X to beneficial but there is then a larger
meta-analysis that shows X is not so good. Suppose further a Scot comes to
you with a diagnosis for which drug X could be used. Does one give the
drug (according to the Scottish study) or withhold it (according to the
meta-analysis)? The problem with ignoring the meta-analysis and treating
the Scot with drug X is that the hierarchy is inverted – and if one does
that, it is not a hierarchy.
This problem is less theoretical than may appear at first. In the albumin
study, although there was no overall benefit described in a much trumpeted
meta-analysis, there was a study of its use in children with meningococcal
septicaemia which showed a benefit(3). Readers were very keen to have the
opinion of the authors and anyone else who was in the news, such as the
editor(4) of the BMJ saying it was harmful, whether they would forbid its
use in their own children if the diagnosis were meningitis. The journals
did not ring with their cries of: “…and not even in my children!” In the
event, the silence of the great men was audible. The shakers shook not.
The leaders - didn’t.
A thought experiment such as the one above is called a gedanken
experiment and has a long history. Einstein used this a lot. Marie Curie
during a Solvay conference, records him lumbering around a foreshore
saying his most important task was to decide what happened when a ray of
light went through a free falling elevator. The earliest example of
thought experiment that springs to mind is Newton and the apple (a maid of
kent, I think) in the late seventeenth century.
In short, hierarchies may have a place in ordering information. The
issue is that a hierarchy is linear. If the information has more than one
dimension, then there will be more than one way to place them in a
hierarchy and not only that, the orderings may be inconsistent with each
other. The same evidence cannot simultaneously validate both of them. If
one is going to favour one way to order and reject the other why not
reject both and conclude the information cannot be validly ordered?
Priests never had this problem.
Hierarchies have a place in theory surrounding medical practice. They
may have a place near the centre, but I do not think that they are so
important that they should be placed anywhere near the top.
Oliver R Dearlove FRCA
Refs
1.D L Hurd JJ Kipling Origins and Growth of Physical Science, Penguin
Books 1964. Introduction
2. Valley Forge v Americans United 454 US 464 (page 15)
3 Levin M, Galassini R, De Munter C, Nadel S, Habibi P, Britto J, et
al. Improved survival in children admitted to intensive care with
meningococcal disease. Proceedings of the 2nd Annual Meeting of the Royal
College of Paediatrics and Child Health. York: Royal College of
Paediatrics and Child Health , 1998.
4. Dearlove O R. A shaft in the Editor’s eye. British Medical
Journal 1999 317 23 also at http://www.bmj.com/cgi/eletters/317/7154/291
Conflict of interest: The author is a Council member of the Royal
College of Anaesthetists. These views are his own and do not represent
those of the Council (or his employer).
Competing interests:
as script
Competing interests: No competing interests