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Vol. 28 No. 2
March-April 2006

Up for Discussion | A forum for members and member organizations to share ideas and concerns.
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Can Ambiguous Terminology Cause a Barrier to Trade?

Paul De Bièvre asked us this question in a recent article published in the CI series, “Emerging Issues in Developing Countries” (CI Sep–Oct 2005, pp. 18–20). The following piece includes both a letter from William Horwitz received in response to De Bièvre’s initial publication, and De Bièvre’s subsequent reply.

Letter from William Horwitz

Now that I am retired and have no professional responsibilities, perhaps I can comment on the article “Emerging Issues in Developing Countries” by my friend Paul De Bièvre that appeared in the Sep–Oct 2005 issue of Chemistry International, pp. 18–20. I have admired Paul over the years for his command of non-native English and his zeal in trying to instill the importance of metrology to ordinary analytical chemists.

As a result of my more than 65 years of practice in regulatory analytical chemistry with the U.S. Food and Drug Administration, with AOAC International, and as the U.S. Delegate to the Codex Alimentarius Committee on Methods of Analysis and Sampling, I am aware of the importance of standards, uncertainty, and metrology. I have always referred to the writings of W.J. Youden, John Taylor, and Grant Wernimont, because these authors were readable and understandable. I also have been exposed to the metrological documents from ISO, VIM, and the corresponding documents from our own NIST, but I must confess that after all this time, this literature is still largely incomprehensible to me. Metrology is fundamental to all measurements, but understanding metrological documents is probably inversely proportional to their importance.

Unfortunately, Paul’s article is another example in obfuscation. I am a type 2 diabetic and my glucose value can vary from day to day by 5 to 10 percent, so the difference in international standards from country to country of perhaps less than 1 percent is an absurd justification for “identical understanding of the same concepts.” It is merely common sense that units should be the same the world around; there should be no problem in obtaining the concurrence of chemists, as in the case of IUPAC nomenclature for organic compounds, when it is presented in understandable terms. The problem occurs because most explanations of the definitions and distinctions in metrology are incomprehensible.

Take the paragraph on “Quantity,” which provides a superb example of the problem. After reading the paragraph innumerable times, I still did not see the distinction between quantity and amount. So I turned to my desk dictionary to find that linguistically a quantity is “1. An amount or portion; either, a measurable or numerical amount; or, loosely, any amount capable of an increase or decrease in kind...05. Math. Whatever may be operated upon according to fixed mutually consistent laws;—distinguished from a magnitude.”

Turning to magnitude: “1. Greatness; as: a Physical greatness...2. a. Size; special quality. b. Quantity, capability of being greater or less. 3. Astron...4. Math. A number assigned to a quantity, by which the quantity may be compared with other quantities of the same class.”

It appears that the distinction that is desired is that “quantity” is the item and “amount” is its magnitude. But then the second sentence destroys this insight: “Thus, in chemical measurement, ‘quantity’ is ‘concentration,’ ‘content,’ ‘amount-of-substance fraction,’ or ‘mass fraction.’ But ‘quantity’ is also used by chemists colloquially to mean ‘amount.’” This then pulls the rug out from under my understanding! Further: “Thus we often talk ambiguously about a ‘quantity of sample.’ If we want to express ‘how much of a substance there is,’ then the term ‘amount’ should be used to avoid confusion.” To me, a 1.0000 gram test portion (not “sample” by IUPAC and ISO nomenclature!) removed from a test sample is an unambiguous quantity or amount, and I do not yet see the distinction.

There, in a nutshell, is the problem that metrologists have: They are unable to clarify the major distinctions they see in concepts that are indistinguishable to the multitude of chemists.

Dr. Horwitz retired from AOAC International (Gaithersburg, Maryland, USA). In the 90’s, he was involved in the IUPAC Analytical Chemistry Division, and more particularly with the former Commission on General Aspects of Analytical Chemistry.

Reply by Paul De Bièvre
It has given me great pleasure that my good American colleague in measurement Bill Horwitz has taken so much notice of my recent article in CI. As it is the explicit intention of this series in CI to be “up for discussion,” I will comply.

I am retired, too, and I do not believe that our professional responsibilities are thereby ended. If one has accumulated professional experience in measurement on the intercontinental scene spanning four decades, and can combine that experience with the ability to look at the measurement scene from a distance in space and time, that constitutes a great asset. In addition, listening to questions from audiences on the six continents is an enormous learning experience. I think both of us should continue to utilize those assets—as Bill does by writing his letter.

However, right away he delivers clear proof of the ambiguity in the English language of a basic concept (and associated term) in measurement: “quantity.” He disputes my statement on the use of “quantity” and supports his argument by the results of his diligent search in various dictionaries, the very purpose of which is to explain terms used in daily language. But the meaning of concepts and terms in measurement are not to be found in a desk dictionary for ordinary language but in a vocabulary, defined by the 2000 ISO International Standard 1087 1, 3.7.2 as a “terminological dictionary which contains designations and definitions from one or more specific subject fields.” For the field of measurement, that is the International Vocabulary of Basic and General Terms in Metrology (i.e., in all measurement), known as the “VIM,” set into existence by international vote in 1983 (ISO).

In the VIM (and such other handbooks, like the IUPAC Green Book Quantities, Units and Symbols in Physical Chemistry) “quantity” and “amount” are not synonyms, despite the fact that Horwitz writes: “After reading the paragraph innumerable times, I still did not see the distinction between quantity and amount.”

Quantities in measurement include mass, length, time, and, more specifically in chemical measurement, mass fraction and concentration. Quantities are the things we measure. Amount is a concept created to help us talk about “how much is there of what we measure?”—usually in terms of numbers of specified entities (in chemistry: the number of specified particles such as atoms, molecules, or ions of a specified substance).

Must we ask the question whether an internationally agreed-upon specific vocabulary is there to be ignored when “globalization” has also come to chemical measurement results, helping us to determine the value of goods in trade? The use of one term for different concepts or the use of several terms for the same concept is a pain in the neck for non–English-speaking people and for those who must translate these terms in 30 to 40 other languages and try to ensure that the same concepts convey equally in all languages.

The continuing use of one of the most ambiguous terms in the English language—the word "standard"—without qualification is another case in point for people who are not trained to the “interpretation in context” so dear to the English-speaking part of the world, especially when he or she comes from a culture with a totally different language structure than the family of European languages.

It is not difficult to point to other similar examples.
Here, in a nutshell, is an ongoing problem for many chemists conducting measurements: Clusters of chemists (e.g., in the food, clinical, environmental, industrial, and isotopic fields) have developed their own terminology, thinking that they had to invent anew their own basic concepts, applicable for their use only, to be understood by themselves only, and usable in a jargon-like fashion. This was done under the assumption that the jargon could be translated in a simple way into other languages. But it cannot.

Basic terms and concepts should be common to all measurement. Common terms and concepts are prerequisites for making meaningful translations in several languages and for intercontinental use.

Large cultural communities, each with their own language, will have to decide whether they want the terms in their language to cover globally understood and agreed-upon concepts. Therefore, they need to respect a common and consistent vocabulary rather than a dictionary. Only then can terms be consistently translated from language to language. If we do not have, consult, or use a common vocabulary (rather than an ordinary language dictionary), how can we speak a common technical language?

Introducing metrological concepts in chemistry is like introducing common communication tools for clarity; it’s a prerequisite for understanding. And understanding is a prerequisite for intercontinental agreements, including trade agreements.

Paul De Bièvre <>, a long-time member of IUPAC, is an independent consultant on metrology in chemistry based in Belgium. He is currently a member of the Interdivisional Working Party for Harmonization of Quality Assurance of the IUPAC Analytical Chemistry Division.

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