If the argument from self-valuation entitles humans to regard their humanity or personhood as valuable, then by the same reasoning Satan would be entitled to regard his devilish nature as valuable.
by the same reasoning(as used in logic and argumentation)
A logical principle meaning that if a rule or argument works in one situation, it should work the same way in similar situations—you can't apply rules unfairly to different cases.
devilish nature(as used in ethics and metaphysics)
The qualities or characteristics that make something evil or harmful; used here to contrast with human nature.
personhood(Presented as the telos of moral agency)
A status achievable through moral achievement, contingent on the exercise of the capacity for virtue.
There are some dangers in this argument, however. One, which Korsgaard considers, is that it might lead to ‘self-conceit’ (Korsgaard 1998: 54. Cf. also Korsgaard 1996: 249–50): that is, I might conclude from this that I am supremely valuable, simply as Bob Stern, which could obviously then get in the way of my ethical treatment of others. But, this worry might be lessened by the thought that while the argument gets me to see that I must find something valuable about me, it need not be anything a