Maximilian Schich maximilian at schich.info
One take-home from large-scale data-integration & data science is that 
even the strongest assumed 1-to-many relationship in reality is 
quasi-1-to-many due to differences in opinion (your tree vs. my tree), 
differences in construction of strong-tree classification systems (e.g. 
material/construction-method vs. construction-method/material in 
architecture), and differences in data preservation (cf. the integration 
of several strong-tree phylogenies based on different knowledge of the 
fossil record). As a consequence it would make good sense to model 
part-of relationships by default to allow for many-to-many at least as 
an exception, even if the ideal is 1-to-many for one reason or another.
Regarding this issue of "part-of as many-to-many", there is a crucial 
difference between more controlled data collections for "data reasoning" 
and a more realistic "data archaeology" that acknowledges the existing 
multiplicity of opinion. In the case of "data reasoning" many-to-many 
may be a computational hurdle. Yet in the case of "data archaeology" 
forced 1-to-many relationships are evil, as they induce an artificial 
discreteness in the data, very similar to the artificial yet often 
conceptually enforced discreteness of races, gender, etc. In this sense 
an artificial restriction of part-of semantics to 1-to-many 
relationships may be a potential source of severe systematic bias that 
needs to be avoided under all cost.
Consequently, there should be an emphasis on "general parts can be 
shared by more than one whole", particularly when facing heterogeneous 
sources of data. At the same time the audience should be provided with 
an explicit explanation why "non-cyclic, wherever it applies" could be a 
desire, while always accompanied by a caveat that "wherever it applies" 
may be true in considerable less cases than intuition would suggest.
*Dr. Maximilian Schich*
Associate Professor, The University of Texas at Dallas, ATEC 
<http://www.utdallas.edu/atec/> & EODIAH 
<https://www.utdallas.edu/arthistory/>
<mailto:maximilian.schich at utdallas.edu?subject=[Appointment]>
www.schich.info <http://www.schich.info/>
> Dear Christian-Emil,
> This is good. There is also another concern that in general parts can 
> be shared by more than one whole. I would, nevertheless, add the 
> constraint that part-of semantics mean also non-cyclic, wherever it 
> applies. Could you check that?
> On 10/13/2019 8:42 AM, Christian-Emil Smith Ore wrote:
>> ​Dear all,
>> I work my way through all the open issues. This issue origins from an 
>> observation by Robert Sanderson that P9 cannot hav ethe cardinality 1 
>> to many and at the same time be transitive. This is correct and will 
>> apply to all transitive properties. A transitive property will always 
>> be many to many.
>> Have to be adjusted:
>> P5, P9, P10,   P73
>> Already many to many
>> P69 ok,​P86 ok, P89 ok, P114 ok, P115 ok, P116 ok, P117 ok, P120 ok, 
>> P127 ok, P139 ok, P148 ok, P150 ok, P165 ok
>> This is just editorial changes and need no discussion.
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