Answer:
I'm not totally sure about this, but it describes men and women as 'distinctions of nature'. I think this might refer to that idea that men are somehow 'naturally superior' to women. Around this time, most women stayed home while men were not only in charge of leading armies, but were also the ones actually working. It was very rare for a woman to be educated in the 18th century, though if they were they would normally be very upper-class. This whole excerpt is comparing several things (kings and their subjects, good and evil, etc.). It says that the distinction between KING and SUBJECT is not religious or natural, meanwhile that between men and women is simply natural and could be no other way. These citizens saw titles such as KING and SUBJECT as ones that could be changed or even abolished altogether, meanwhile the difference between men and women is something natural that is inexorable.