Editing Genus–differentia definition (section)

== Multiplicity ==
When multiple definitions could serve equally well, then all such definitions apply simultaneously. Thus, ''a&nbsp;square'' is a member of both the genus ''<span style="white-space: nowrap">[a] rectangle</span>'' and the genus ''<span style="white-space: nowrap">[a] rhombus</span>''. In such a case, it is notationally convenient to consolidate the definitions into one definition that is expressed with multiple genera (and possibly no differentia, as in the following):
* ''a square'': <span style="background:LightSalmon">a rectangle</span> and <span style="background:LightBlue">a rhombus</span>.
or completely equivalently:
* ''a square'': <span style="background:LightBlue">a rhombus</span> and <span style="background:LightSalmon">a rectangle</span>.

More generally, a collection of <math>n>1</math> equivalent definitions (each of which is expressed with one unique genus) can be recast as one definition that is expressed with <math>n</math> genera.{{citation needed|date=December 2021}} Thus, the following:
* ''a Definition'': a Genus<sub>1</sub> that is a Genus<sub>2</sub> and that is a Genus<sub>3</sub> and that is a... and that is a Genus<sub>n-1</sub> and that is a Genus<sub>n</sub>, which has some non-genus Differentia.
* ''a Definition'': a Genus<sub>2</sub> that is a Genus<sub>1</sub> and that is a Genus<sub>3</sub> and that is a... and that is a Genus<sub>n-1</sub> and that is a Genus<sub>n</sub>, which has some non-genus Differentia.
* ''a Definition'': a Genus<sub>3</sub> that is a Genus<sub>1</sub> and that is a Genus<sub>2</sub> and that is a... and that is a Genus<sub>n-1</sub> and that is a Genus<sub>n</sub>, which has some non-genus Differentia.
* ...
* ''a Definition'': a Genus<sub>n-1</sub> that is a Genus<sub>1</sub> and that is a Genus<sub>2</sub> and that is a Genus<sub>3</sub> and that is a... and that is a Genus<sub>n</sub>, which has some non-genus Differentia.
* ''a Definition'': a Genus<sub>n</sub> that is a Genus<sub>1</sub> and that is a Genus<sub>2</sub> and that is a Genus<sub>3</sub> and that is a... and that is a Genus<sub>n-1</sub>, which has some non-genus Differentia.
could be recast as:
* ''a Definition'': a Genus<sub>1</sub> and a Genus<sub>2</sub> and a Genus<sub>3</sub> and a... and a Genus<sub>n-1</sub> and a Genus<sub>n</sub>, which has some non-genus Differentia.