I am a little bit at loss with the following sentence as it uses four different negations:
"朴世堂沒有說無用於日常之說非古之道，也未說因此而不需要它，但是他指出，程子之說未能明示性的本質".
I am not sure how to translate them into English in a way that preserves the original the sentence structure and style.
朴世堂 沒有說(didn't say)無用(not useful)於日常之說非(is not)古之道，也未說(also didn't say)因此(because of that)而不需要(not needing)它，但是他指出，程子之說未能(has not)明示性的本質.
"朴世堂沒有說, 無用於（于?）日常之說（法）非古之道，
Pu ShiTang didn't say, a theory, which is useless in daily life, is not the way of old,
也未說因此而不需要它，
(he) also never said, "Thus we don't need it",
但是他指出，
but he pointed out,
程子之說（法）未能明示性的本質".
Cheng Zi's theory did not clearly show the original nature of sex.
