To Florus 4.91
With what shamelessness, then, do you both approve my statement and refuse to abandon your doctrine? The statements of the two sides cannot be joined by any agreement, since opposite assertions do not share the truth at the same time. If I agreed that sin was natural, I would necessarily fall away from the force of the statement that sin can exist only in free will. In the same way, you, by agreeing that I spoke rightly in declaring that no sin exists without will, should immediately have rejected the opinion by which you believed sin to be natural.
Latin
Qua ergo tu impudentia et approbas sententiam meam, et tuum dogma non deseris; cum sententiae utriusque partis ita nullo possint foedere copulari, ut enuntiatorum opposita pariter non participant veritati? Quomodo ergo ego si consentirem naturale esse peccatum, necesse erat ut deciderem de iure sententiae, quae praescribit, nisi in voluntate libera peccatum esse non posse; ita tu e regione consentiens me bene dixisse, qui pronuntiavi nullum esse sine voluntate peccatum, reicere statim debuisti illam opinionem, qua peccatum naturale credebas.