The existence of extrinsic goodness requires unconditional human worth—that means we must treat others as ends in themselves. Christine Korsgaard writes in 1983 that
The argument shows how Kant’s idea of justification works. It can be read as a kind of regress upon the conditions, starting from an important assumption. The assumption is that when a rational being makes a choice or undertakes an action, he or she supposes the object to be good, and its pursuit to be justified. At least, if there is a categorical imperative there must be objectively good ends, for then there are necessary actions and so necessary ends (G 45-46/427-428 and Doctrine of Virtue 43-44/384-385). In order for there to be any objectively good ends, however, there must be something that is unconditionally good and so can serve as a sufficient condition of their goodness. Kant considers what this might be: it cannot be an object of inclination, for those have only a conditional worth, “for if the inclinations and the needs founded on them did not exist, their object would be without worth” (G 46/428). It cannot be the inclinations themselves because a rational being would rather be free from them. Nor can it be external things, which serve only as means. So, Kant asserts, the unconditionally valuable thing must be “humanity” or “rational nature,” which he defines as “the power set to an end” (G 56/437 and DV 51/392). Kant explains that regarding your existence as a rational being as an end in itself is a “subjective principle of human action.” By this I understand him to mean that we must regard ourselves as capable of conferring value upon the objects of our choice, the ends that we set, because we must regard our ends as good. But since “every other rational being thinks of his existence by the same rational ground which holds also for myself’ (G 47/429), we must regard others as capable of conferring value by reason of their rational choices and so also as ends in themselves. Treating another as an end in itself thus involves making that person’s ends as far as possible your own (G 49/430). The ends that are chosen by any rational being, possessed of the humanity or rational nature that is fully realized in a good will, take on the status of objective goods. They are not intrinsically valuable, but they are objectively valuable in the sense that every rational being has a reason to promote or realize them. For this reason it is our duty to promote the happiness of others-the ends that they choose-and, in general, to make the highest good our end.
Thus because Humanity is the only unconditionally valuable thing the value for todays round is Humanity. Respecting humanity entails a right to liberty actions without consent treat humans as means to an end. Christine Korsgaard 1993 explains
According to Kant, you treat someone as a mere means whenever you treat [them] in a way to which [they] could not possibly consent. xli Kant’s criterion most obviously rules out actions which depend upon force, coercion, or deception for their nature, for it is of the essence of such actions that they make it impossible for their victims to consent. If I am forced I have no chance to consent. If I am deceived I don’t know what I am consenting to. If I am coerced my consent itself is forced by means I would reject. xlii So if an action depends upon force or deception or coercion it is impossible for me to consent to it. To treat someone as an end, by contrast, is to respect [them] his right to use [their] his own reason to determine whether and how [they] will contribute to what happens.
Thus the Value Criterion is Respecting Liberty.