Just as Lange criticized Wolffian metaphysics for reducing the role of God in creation, similarly he criticizes Wolffian ethics for reducing the role of God in upholding morality. True, Wolff does admit that knowledge of God does make a moral person blessed – if we are convinced of God's existence, we can be serene in our belief that God will in course of time reward moral people with peaceful and happy life, while the opposite fate waits immoral people. Yet, just like Wolffian God tends to avoid miracles and has preferred to use natural mechanisms to further his goals, similarly the rewards and retributions are mostly just natural results of the very state of mind caused by belief and non-belief in God – God did not need to even exist, because only the belief in him is required for its beneficial results.
Furthermore, Lange refrains Wolff for accepting the possibility of truly moral atheists and even moral societies of atheists. In Lange's eyes, Wolff's worst mistake is to assume that moral laws could be natural in the sense that they required no reference to an obligation towards a lawgiver. In effect, Lange thinks that Wolff can manage this feat only by confusing self-interest with morality – what is good according to Wolff can be found out by reasoning what is the best outcome for me. Indeed, Lange has no difficulties in pointing out how Wolff considers becoming reasonably wealthy a moral responsibility – he might as well have mentioned the duties of eating well and wearing warm clothes that I ridiculed in my consideration of Wolffian ethics. We see here how Lange's criticism parallels the more general criticism of consequential ethics by Kant – moral worth of an action should not be based on how well it serves my wellbeing.
Lange is also not satisfied with Wolff's primary principle of morality: make yourself and others more perfect. In semblance this command might even feel Christian. But when Christianity commands humans to be perfect, it does this to emphasize their imperfect and sinful state. Wolff, on the other hand, appears to believe that humans can by themselves become truly perfect and self-sufficient: a true blasphemy to a pietist like Lange.
Lange also doubts that Wolffian morality could truly fulfill the second requirement of its primary principle. Indeed, I have also noted that Wolff does not properly justify how the command to perfect others follows from a need to perfect oneself – this might be justified through the harmony of all substances, that is, by stating that when I perfect another person, I am also perfecting myself, but Wolff leaves this completely implicit. Furthermore, as we also saw, Wolff mostly advocated leaving other people to fend for their perfection themselves, because every person should try to be a self-sufficient totality – a final proof of an egotist morality.
In addition, Lange also doubts whether Wolff's ethics is really in line with his metaphysics. He is especially skeptic of the possibility of reconciling independence of body and soul with Wolff's commands to take care of bodily matters. Of course, Wolff can explain these commands as simplified commands to take care of your soul and let body follow through the pre-established harmony, but this does make his ethics somewhat complex.
So much for Lange's criticism, next it is appropriate to see how Wolff answers some of Lange's points.