Query: formido oppositi?

Here, as promised earlier, is another query from me that I hope will encourage others to send me their own queries this summer:

Might anyone have information on the origins of the notion of ‘formido oppositi’ ?  Among Latin scholastic authors, it’s regularly said to be the defining feature of opinion, but where does this come from?

(The best way to respond, I might add, is to “leave a reply,” below.)

Query: Orthography?

As promised, here is a summer query of my own.  Please send me yours, and I’ll happily post them.

Along with Christophe Grellard, Zenon Kaluza, and Aurélien Robert, I am working on a new edition of Nicholas of Autrecourt’s Tractatus (aka the Exigit Ordo).  Because the work is known to survive in only one manuscript, we feel some temptation to preserve the manuscript’s orthography. But we hesitate, because it is not clear that this has significant value to scholars, and clearly there are attendant inconveniences. Hence, we solicit your advice.