A common objection to natural law, albeit in academic garb:
Given the implications of deconstructionism and the “linguistic turn,” what one person or culture means by “life,” “nature,” or “human flourishing” is not the same thing that another person (or culture) means when he uses those terms. They both play by independent rules, given their respective language games, and so they are separated by a chasm that can’t be bridged. Ergo, natural law is rendered linguistically effete.