The Metaphysics of Morals by Immanuel Kant Chapter 2 Page 93

himself, be never employed merely as means, but as the supreme condition restricting the use of all means, that is in every case as an end likewise.

It follows incontestably that, to whatever laws any rational being may be subject, he being an end in himself must be able to regard himself as also legislating universally in respect of these same laws, since it is just this fitness of his maxims for universal legislation that distinguishes him as an end in himself; also it follows that this implies his dignity (prerogative) above all mere physical beings, that he must always take his maxims from the point of view which regards himself and, likewise, every other rational being as law-giving beings (on which account they are called persons).

In this way a world of rational beings