The Medieval Church · c. 1323–1324
The Conduct of Inquiry into Heretical Depravity
Bernard Gui · c. 1261–1331
What it is
An inquisitor's manual describing the beliefs of Cathars, Waldensians, and Spiritual Franciscans, with model interrogations and the sentences appropriate to each.
Why it lasted
Catalogued because it must be known: the machinery of persecution set out by a practitioner, and paradoxically a main source for what its victims believed.
Where to read it
This work is in the public domain and can be read in full, free, at the archives below. The Library catalogues it; it does not host the text.
These open a search on each archive rather than a direct link, which is the honest way to point at an edition nobody here has checked line by line.
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