John Rawls was far and away the most influential political philosopher of the last century.
If you want to argue for maximin using decision theory when you don't know the probabilities, I think the standard approach would be to appeal to Gilboa and Schmeidler (1989). A more modern version is Kochov
https://drive.google.com/file/d/1HH_zngDGUazCKEQ_bBOYOejbF15sRWNv/view
I'm not convinced by these arguments, but just mentioning in fairness.
If you want to argue for maximin using decision theory when you don't know the probabilities, I think the standard approach would be to appeal to Gilboa and Schmeidler (1989). A more modern version is Kochov
https://drive.google.com/file/d/1HH_zngDGUazCKEQ_bBOYOejbF15sRWNv/view
I'm not convinced by these arguments, but just mentioning in fairness.