"Problems with the appeal to nature
Presumably, the single most difficult challenge that Modern Stoicism faces is its relationship to the core principle of Ancient Stoicism, that is to the principle of “following nature.” In a word, the Ancient Stoics put forward it was unquestionable that in order to live a good life, one needed to live consistently with nature. According to the Ancient Stoics, nature was by definition good and everything which was conformable to nature was deemed good. Moreover, the Ancient Stoics had a teleological outlook on the world, that is, they held that everything in the universe was purposefully and rationally organized to a good end." You can read more here about modern Stoicism:
[en.wikipedia.org]