Full Idea
Duns Scotus endorsed Avicenna's theory of the common nature, according to which the essences have an independence and priority to their existence as either universal in the mind or singular outside it.
Gist of Idea
Avicenna and Duns Scotus say essences have independent and prior existence
Source
report of John Duns Scotus (works [1301]) by Stephen D. Dumont - Duns Scotus p.206
Book Reference
'Shorter Routledge Encyclopaedia of Philosophy', ed/tr. Craig,Edward [Routledge 2005], p.206
A Reaction
I occasionally meet this weird idea in modern discussions of essence (in Lowe?), and now see its origin. It makes little sense without a divine mind to support the independent essences. Scotus had to add a principle of individuation for essences.
Related Idea
Idea 22127 Scotus said a substantial principle of individuation [haecceitas] was needed for an essence [Duns Scotus, by Dumont]