-- deiner = _tuus_.

In these differences of form lie the best reasons for the assumption of a
genitive case, as the origin of an adjectival form; and, undoubtedly, in
those languages where both forms occur, it is convenient to consider one as
a case and one as an adjective.

s. 400. But this is not the present question. In Anglo-Saxon there is but
one form, _min_ and _thin_ = _mei_ and _meus_, _tui_ and _tuus_,
indifferently. Is this form an oblique case or an adjective?

This involves two sorts of evidence.

s. 401. _Etymological evidence._--Assuming two _powers_ for the words _min_
and _thin_, one genitive, and one adjectival, which is the original one?
Or, going beyond the Anglo-Saxon, assuming that of two _forms_ like _meina_
and _meins_, the one has been derived from the other, which is the
primitive, radical, primary, or original one?

Men, from whom it is generally unsafe to differ, consider that the
adjectival form is the derived one; and, as far as forms like _m[^i]ner_,
as opposed to _m[^i]n_, are concerned, the evidence of the foregoing list
is in their favour. But what is the case with the Middle Dutch? The
genitive _m[^i]ns_ is evidently the derivative of _m[^i]n_.

The reason why the forms like _m[^i]ner_ seem derived is because they are
longer and more complex than the others. Nevertheless, it is by no means an
absolute rule in philology that the least compound form is the oldest. A
word may be adapted to a secondary meaning by a change in its parts in the
way of omission, as well as by a change in the way of addition.

s. 402. As to the question whether it is most likely for an adjective to be
derived from a case, or a case from an adjective, it may be said, that
philology furnishes instances both ways. _Ours_ is a case derived, in
syntax at least, from an adjective. _Cujum_ (as in _cujum pecus_) and
_sestertium_ are Latin instances of a nominative case being evolved from an
oblique one.

s. 403. _Syntactic evidence._--If in Anglo-Saxon we found such expressions
as _doel min_ = _pars mei_, _hoelf thin_ = _dimidium tui_, we should have a
reason, as far as it went, for believing in the existence of a true
genitive. Such instances, however, have yet to be quoted.

s. 404. Again--as _min_ and _thin_ are declined like adjectives, even as
_meus_ and _tuus_ are so declined, we have means of ascertaining their
nature from the form they take in certain constructions; thus, _mi-nra_ =
_me-orum_, a