Write briefly about Kant’s theory of natural law and the categorical imperative?

[Jurisprudence] After Rousseau, Kant made man a rational entity an end in himself and developed the theory of natural law and the categorical imperative. His categorical imperative was a derivative form of general will of Rousseau-which identified rationality with freedom of will the former to guide and dictate the individual to follow his conscience. The freedom of will in Kant is nothing more than the human right of self determination.