A primitive connection relation the is the beginnings in any (mereo)topological theory.
is (should be) symmetric and reflexive
containment, where NONE of the outer side of the part contained in the whole touches the border of the whole. (cf. tangential)
example: a cell nucleus is NTPCI a cell, a human heart it NTPCI a human body.
location (2D, still), where NONE of the outer side of the part located in the whole touches the border of the whole. (cf. tangential).
example: Lesotho is NTPLI South Africa (well, geographically; they are two distinct legal entities)
containment, where SOME of the outer side of the part contained in the whole touches the border of the whole. (cf. non-tangential)
location, where SOME of the outer side of the part located in the whole touches the border of the whole. (cf. non-tangential).
example: South Tyrol is TPLI Italy (as it's a border province, bordering with Austria)