>Robert Bushnell wrote in USMA 07859: >In 17784 and 17787 Louis Jourdan gives the term "quantity" as defined by ISO. >Now that this is raised here, I comment. > >Quantity is discussed at length by J. de Boer in Metrologia 1994/95 32 pp >405-429, >"On the History of Quantity Calculus in the International System". > >I object to saying that each of mass, length, time, etc. is a "quantity". >Rather I >say that these are properties. I submitted a letter (1999 Jan 21) to >Metrologia >pointing out logical errors in de Boer's paper. Metrologia rejected the >letter, >saying it is not scientific. It may not be scientific but it is directly on >the >subject of de Boer's paper. The rejection tells me that Metrologia is not >interested in promotion of public understanding and use of SI. Its job is >reporting >on scientific improvement of fundamental standards. > >My objection is that "quantity" means "how much" to most people. >Consequently, >our documents are obscure. At times de Boer uses "quantity" to mean "how >much" >and at times to mean "property". This confusion appears in French in >"grandeur". >The French and English dictionaries that I have show both meanings. That is, >"quantity" in SI has a special meaning which the general public never hears >about: >"that property of anything that can be determined by measurement". En >francaise >le 7em sense de "grandeur" est "MATH Tout ce a quoi on peut affecter une >valeur >dans un systeme d'unites de mesure". Outside of SI "quantity" means "how >much" >and "amount". > >To see the confusion, read the words in 17787 substituting for "quantity", >"property" in a reading and "amount" in a second reading. Read them outloud >for >the best effect. > >I give one example: b) particular properties: > - length of a given rod. > b) particular amounts: > - length of a given rod. >Which is it? properties or amounts. Can one of these words be used >throughout? > > >The committee revising SI10 rejected my view without recent discussion so the >2002 issue still has "quantity" as the column heads in the tables of prope >rties >and units. "Quantity" and "grandeur" are firmly established in CCU, CIPM, >CGPM, >ISO and NIST. This is not going to change. > >This does not help us sell SI measures. I hesitate to refer people to our >standards. >Teachers must be careful if they use the standards. > >Let me know your thoughts. > Robert Bushnell
I see your point. "Quantity" seems to be well established in scientific jargon. Hence in speaking to the general public we should avoid the term, or explain what it means in a perticular context. How is this: "quantity is a measurable property of something, or the numerical value of that property"? Joseph B.Reid 17 Glebe Road West Toronto M5P 1C8 TEL. 416-486-6071
