Full Idea
A morally good attitude of mind (or virtue) claims the intrinsic value of dignity, because it affords a rational being a share in the making of universal law, which therefore fits him to be a member in a possible kingdom of ends.
Gist of Idea
Virtue lets a rational being make universal law, and share in the kingdom of ends
Source
Immanuel Kant (Groundwork of the Metaphysic of Morals [1785], 435.79)
Book Reference
Kant,Immanuel: 'The Moral Law (Groundwork of Morals)', ed/tr. Paton,H.J. [Hutchinson 1948], p.97