On an un-Leibnizian requisite

I examine the new defense of the principle of sufficient reason, offered by Michael Della Rocca (_The Journal of Philosophy_, 120 (2023): 220-227). I first identify a crucial premise of Della Rocca’s argument, and argue that it is not justified. I then reformulate his argument, this time with the corresponding crucial premise justified. Finally, although I think the reformed argument is valid, I express some doubts about the propriety of the un-Leibnizian requisite suggested in that paper.