uom-ontology-std
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## Re: [uom-ontology-std] What is mass?

 To: uom-ontology-std Ed Barkmeyer Fri, 25 Sep 2009 13:16:02 -0400 <4ABCFAD2.1090409@xxxxxxxx>
 ```John F. Sowa wrote:    (01) > The UoM ontology should be compatible with a very wide range > of incompatible ontologies that people have developed or > proposed. If we start defining too many upper-level concepts, > we will end up with one more incompatible ontology. > > Therefore, I propose that we take the terms that lead to > endless rounds of discussion and declare them to be > undefined primitives. That would allow them to be linked > to a wide range of different upper levels that other people > have proposed.    (02) Most of this debate is about first getting past the terms to agree on the concepts, and then getting agreement on whether specific concepts are needed.    (03) But if we take John's guidance at his word, the following are undefined primitives: Quantity, Kind of Quantity, Quantity Magnitude, Dimension, Unit of Measure. Now, what sort of ontology will we make with those undefined terms? Do they have any properties? What axiom can we write?    (04) Well, we can do what UCUM does: There are relationships among units of measure and those relationships can be expressed mathematically as an algebra. But comparability and equality are only partly defined by the algebra. In effect, the algebra defines two units to be either 'incomparable' or 'possibly comparable', and it defines two 'possibly comparable' units to be 'unequal' or 'possibly equal'. The user needs to add an external rule to get from 'possibly comparable' to 'comparable' and thence to 'equal'. Would you be satisfied with that, John?    (05) > Fundamental principle: Detailed axioms and definitions create > incompatibilities and inconsistencies. Never define anything > that you don't absolutely need for the problem at hand. > > This strategy is one more example of my general approach > to axioms: > > When in doubt, throw it out. >    (06) Well, John, what precisely is the problem at hand? That is the question Gunther was trying to answer.    (07) He avers that you don't need to understand 'quantities' in the VIM and SI sense, in order to produce a useful (mathematical) semantics for units of measure. And that is true from the point of view of manipulation -- a units of measure calculus does not require the semantics of quantity, anymore than Newton's calculus required a semantics of physics. In that view, if there is a right answer, the UCUM mathematical model will produce it. But the mathematical model can also produce meaningless answers. Gunther's position is that the avoidance of meaningless answers requires a further ontology that conveys the science of the problem space, and there are many of those.    (08) NIST (Martin Weber and I) have argued that the ontological model of a unit of measure that supports knowledge engineering _in general_ cannot be purely mathematical. We don't want a reasoner to use valid mathematics and nonsense physics to produce the proof of a conjecture. But unlike Gunther, we believe that the general science of measurement is not specific to the science of particular problem spaces, and the exceptions (like particle physics) are very few. We also believe that to be the position of the BIPM, which is why their publications do not get deeply into electricity or mechanics or chemistry. And we believe that most science, most engineering and almost all business uses of units of measure would benefit from an ontology that understands the semantics of units in terms of the semantics of quantity.    (09) As Gunther pointed out, this is a critical question for the project.    (010) So, instead of Zen Principles of Ontology Design, what you could contribute is a position on the question.    (011) -Ed    (012) -- Edward J. Barkmeyer Email: edbark@xxxxxxxx National Institute of Standards & Technology Manufacturing Systems Integration Division 100 Bureau Drive, Stop 8263 Tel: +1 301-975-3528 Gaithersburg, MD 20899-8263 FAX: +1 301-975-4694    (013) "The opinions expressed above do not reflect consensus of NIST, and have not been reviewed by any Government authority."    (014) _________________________________________________________________ Message Archives: http://ontolog.cim3.net/forum/uom-ontology-std/ Subscribe: mailto:uom-ontology-std-join@xxxxxxxxxxxxxxxx Config/Unsubscribe: http://ontolog.cim3.net/mailman/listinfo/uom-ontology-std/ Shared Files: http://ontolog.cim3.net/file/work/UoM/ Wiki: http://ontolog.cim3.net/cgi-bin/wiki.pl?UoM_Ontology_Standard    (015) ```
 Current Thread Re: [uom-ontology-std] What is mass?, (continued) Re: [uom-ontology-std] What is mass?, Martin S. Weber Re: [uom-ontology-std] What is mass?, John F. Sowa [uom-ontology-std] Java Scientific Computing Project JSR 275, Gunther Schadow Re: [uom-ontology-std] What is mass?, Pat Hayes Re: [uom-ontology-std] What is mass?, John F. Sowa Re: [uom-ontology-std] What is mass?, Joe Collins Re: [uom-ontology-std] What is mass?, Pat Hayes Re: [uom-ontology-std] What is mass?, Gunther Schadow Re: [uom-ontology-std] What is mass?, John F. Sowa Re: [uom-ontology-std] What is mass?, ingvar_johansson Re: [uom-ontology-std] What is mass?, Ed Barkmeyer <= Re: [uom-ontology-std] What is mass?, ravi sharma Re: [uom-ontology-std] What is mass?, Martin S. Weber Re: [uom-ontology-std] What is mass?, Joe Collins Re: [uom-ontology-std] What is mass?, Martin S. Weber Re: [uom-ontology-std] What is mass?, Joe Collins Re: [uom-ontology-std] What is mass?, ravi sharma Re: [uom-ontology-std] What is mass?, Martin S. Weber Re: [uom-ontology-std] What is mass?, Pat Hayes Re: [uom-ontology-std] What is mass?, ingvar_johansson Re: [uom-ontology-std] What is mass?, Weber, Martin S.