For instance, if I wanna write: one should not be judgmental if they don't know the truth. Is this correct?
I found this structure e.g. One is said to communicate successfully when he or she is able to express what he or she feels is a bit redundant, I have to repeat he or she all the time.
So, what pronoun should I use in order to refer the previous ONE when I'm writing in the way in the example sentence?