Does the unity of reason imply that epistemic justification is factive?

Some externalists have recently argued that the unity of theoretical and practical reason implies that epistemic justification is factive. It is argued that arguments for the factivity of epistemic justification either (i) equate two actions that are in fact different, or (ii) make the unwarranted assumption that the by-relation transmits justification. The unity of reason does not imply that epistemic justification is factive. [ABSTRACT FROM AUTHOR]