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...amateur...eutectics...might as well be voodoo...

updated tue 23 nov 99


elizabeth priddy on mon 22 nov 99

let me rephrase, then...

amateur chemists mixing glazes in their studios
without the rigor of science to back them up
and explain the eutectics involved in many
layered chemical blends and reliably predict
results might as well be voodoo for as much as
one will obtain repeatable results.

or "...amateur...eutectics...might as well be

This is what I meant to say in the first place,
but I needed your background post to qualify
that statement and I couldn't have stated the
case as well as you did. Please see my post on
a "kinder, gentler kiln/chemistry suggestion"
to further this thought.

science is great, but it ain't art, & vice versa

Elizabeth Priddy

Clay: 12,000 yrs and still fresh!

On Sun, 21 Nov 1999 16:31:06 Gavin Stairs wrote:
>----------------------------Original message----------------------------
>At 05:05 PM 20/11/99 , you wrote:
>>----------------------------Original message----------------------------
>>eutectics is voodoo and is one of the main
>>reasons I have as little interest in glaze
>>chemistry as I do. Also not a pyro...
>No, Elizabeth, not Voodoo. Chemistry.
>Folks, a lot of people have spent their lifetimes working out how things go
>together, and what happens when they do. We call them
>scientists. Chemists. What they have left for the rest of us is a
>systematic, repeatable description of their findings. The stuff that just
>ain't so has been thrown out: what's left is what does work, each time you
>do the experiment. This work can be the basis of what we call predictive
>science: being able to say before you do something what the outcome will
>be. This is not Voodoo, which is a very respectable system in its own
>right. It is science. This doesn't cover everything possible, but it does
>cover most of the basics of what is called natural material ceramics, or
>pottery and glazing. The true scientists are off at the frontiers,
>battling for new knowledge, while the rest of us practicing engineers are
>trying to apply the old science to the practical problems of traditional
>pottery, glazing and kilns.
>What is wrong here is the idea that people who have had no training in the
>system should be able to jump in at the deep end and not drown (make
>sense). It's just not reasonable. Art schools and artists are noticeably
>lacking in science training. This is not astonishing, really. The problem
>is that understanding glaze chemistry is at the far out edge of predictive
>science. What we have here is oil and water.
>The science-knowledgeable people on this list are making valiant attempts
>to reduce the science to words of few syllables and concepts familiar to
>people who have not been introduced to the rudiments of the scientific
>arts, like thermodynamics (and the dynamics in thermodynamics means change,
>by the way: thermodynamics is by no means limited to statics, or
>equilibrium states), and calculus. I have great respect for the geologists
>who are attempting to explain what I know to be exceedingly complex
>chemical systems. There is no time on this list to cover all the
>introductory ground, to explain why differentiation occurs, to explain the
>dynamic equilibrium of multiple phase systems, to explain what diffusion
>is, and how it works in systems as disparate as flame dynamics and magma
>melts. Most working scientists simply don't have the time to make the
>attempt. These are people who have attended university for a minimum of 4
>years, and many much longer, to attain their credentials and preparatory
>knowledge, and who have then practiced their specialties for many more
>years, to gain their intimate knowledge of these systems.
>Now, the artist potters on this list have studied quite as long in a
>different direction. They have learned many things about their art, but
>unfortunately in a craft like potting, very little about the science. They
>certainly have a practical base, but it is not of a nature which allows
>them any predictive confidence. Unfortunately again, in this era we are
>all expected to have an understanding of the behaviour of our products, at
>least insofar as the safety of the users of our wares is concerned. That
>is why some of us are concerned that potters not trained in science should
>become at least sensitized to the inherent dangers of glaze and body
>chemistry, and perhaps even a bit knowledgeable in the realms of
>science. The renaissance man/woman is demanded by these circumstances.
>Yes, there is a certain amount of noise on the list, from people who speak
>beyond their knowledge. Yes, this is confusing. But do understand that it
>is very costly in terms of time and money to mount convincing and
>instructive demonstrations of the phenomena we discuss. Especially if you
>want to do so with the integrity and rigor of a scientist. The
>universities should be funding this and carrying it out, but they have
>their own agendas, apparently. So truly knowledgeable people will often
>speak of things which they know to be true, but have not demonstrated by
>specific experiment. Perhaps one day...
>As to the noise: No-one should be an uncritical reader. One of the first
>lessons of science is that one must understand what is being taught, and
>judge whether it is reliable, based on one's prior knowledge. The best
>learning experiments are designed to explode ill founded preconceptions by
>confronting them with contradictory reality. Learning is quite as much a
>case of removing old, ill conceived "knowledge" as it is providing
>new. When you read something that you think is wrong, confront it with an
>experiment, or with accurate observation. Similarly, when someone asserts
>something which you think is right, see if it agrees with your
>experience. In either case, look critically and carefully at what you take
>to be real. Seeing scientifically is like proofreading: you can read the
>same passage over and over and still miss the error that someone else can
>pick up in a momentary glance.
>Dear Elizabeth, if you are still with me, the "Voodoo" is not in eutectics,
>which are precisely defined chemical states which define the boundaries
>between chemical regimes in polyphase systems. It is in the imprecise
>understanding of the terms and the underlying systems. If one wants to
>understand, one must make the effort to get it right. And it is in trying
>to ignore reality while pursuing ill-founded recipes and old saws. Science
>isn't everything, but it is a great deal more than nothing.

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