Definition: From Oriel to St. John's and back

One reads R. Robinson's _Definition_. One then reads Grice, Conception of Value, and one wants to re-read Aristotle on 'essence'.

For consider what Grice writes in _Conception of Value_. He is playing with a logical conception of 'essence'. Grice writes that, "in its _logical_ dress", an essential property P could appear as either

i. a "property which is CONSTITUTIVE
or DEFINITIVE of a given kind"

OR

ii. the "individuating" property of an
individual member of a given kind.

It is "clear", he notes that if an essential property is (i) -- i.e. "a property that DEFINES a kind" -- then it is also (ii) -- but the reverse may not hold.

This leads Grice to a METAPHYSICAL CONCEPTION OF 'ESSENCE', rather. In trying to 'find room' for an 'Aristotelian idea' of essence which has 'at least until recently been pretty unpopular', he goes on to suggest that

"there is another more metaphysical dress" which an essential property may wear, and which combines nicely with Hamilton's observations above regarding Aristotle's use of 'aitia' and what Hamilton calls 'a mathematical conception of a definition'.

An essential property may appear, Grice writes, as

"a Keynesian generator-property".

i.e. "a 'core' property of a [substantive] kind which co-operates to

*explain the phenomenal [and dispositional] features*

of individual members of a kind".

COMBINING THE LOGICAL AND THE METAPHYSICAL. Grice writes: "Perhaps at least at the level of a type of theorising which is not too sophisticated and mathematicised, as maybe these days the physical sciences are", the *logically* essential property and the fundamentally explanatory property of a substantial kind

_come together_.

A "substance" would be, essentially (in the *logical* sense) a thing such that

in a circumstance C it manifests a feature F

-- where the gap-signs are placed in such a way as to display "the most basic laws of the theory." Perhaps at _this_ level of theory, a substance requires a theory to give expression to its nature and a theory requires a substance to govern them.
(H. P. Grice, _The Conception of Value_. Oxford: Clarendon Press, p. 112).
(There is a passing ref. by Grice to work by his colleague at UC/Berkeley
here -- G. Myro.).

I'm not sure I'd agree with Grice that there is an element of _contingency_
here and that the "combo" of logical-cum-metaphysical is exercised only "at the level of a type of theorising which is not too sophisticated and mathematicised", though, but then _I_ am not too sophisticated (or mathematicised, for that matter).

Etc.

Refs.
Aristotle, Organon.
Grice HP. The conception of value. Oxford: Clarendon
Keynes JM. Cited by Grice.
Myro, G. Essence.
Robinson R. Definition. Oxford.