Here are some of the best justifications for a Gewirth framework.
Justice aims to provide a structure that can guide an agent’s actions. We must ensure that the ethic itself does not contradict the idea of agency [otherwise it would be incoherent for agents to accept the normative structure of any ethic, collapsing to nihilism.] Contained in agency is the ability to act for a purpose. If an agent regards their purpose as important, they must regard the means required to that purpose as important. MONTANA:
The Gewirthian Principle of Generic Consistency as a Foundation for Human Fulfillment: Unveiling a Rational Path for Moral and Political Hope. Robert A. Montana. June 2009.
An entailment that naturally follows from the agent’s pursuit of what has been deemed as good for him is the assertion that freedom and well-being, features that are necessary for him to achieve [their] ends, are necessarily good. It is here where Gewirth’s insistence upon logical consistency comes in—that this agent cannot, without contradicting himself, utter the goodness of that which is pursued without complementing his statement as regards the goodness of the freedom and well-being necessary for him to achieve this end. The positing of this necessity then entails another statement where “[they] logically must hold that he has rights to these generic features, and he implicitly makes a corresponding right-claim.” When a deluge of critiques came with this transition to a right claim, Gewirth, together with other apologists, explained that, at this point, the claim still remained reflective—or has not yet gone beyond the agent. This transition is valid for Gewirth, further, because of his notion that action has both a deontic and evaluative structure, where the relation between the evaluative judgment (that freedom and well-being are necessary) and the deontic judgment (that he has rights to freedom and well-being) fit within the general framework of this structure.
To deny that freedom, the ability to choose purposes, and well-being, the ability to realize those purposes, are important would be to deny the purpose was important. An agent must view themselves as having a right to freedom and well being, since one condition of achieving freedom and well-being is that other agents do not violate your freedom and well-being. This results in universal human rights. GEWIRTH:
Alan Gewirth [ Prof at U Chicago] “Human Rights: Essays on Justification and Applications. Essay 1, the Basis and content of Human Rights. 1982
Thus far I have shown that rights and right claims are necessarily connected with action, in that every agent, on pain of self-contradiction, must hold or accept that he has rights to the necessary conditions of action. I shall henceforth call these generic rights, since freedom and well-being are the generic features of action. As so far presented, however, they are only prudential rights but not yet moral ones, since their criterion, as we have seen, is the agent's pursuit of his own purposes. In order to establish that they are also moral and human rights, we must show that each agent must admit that all other humans also have these rights. For in this way the agent will be committed to take favorable account of the purposes or interests of other persons besides himself. Let us see why he must take this further step. This involves the question of the ground or sufficient reason or sufficient condition on the basis of which any agent must hold that he has the generic rights. Now this ground is not subject to his optional or variable decisions. There is one, and only one, ground that every agent logically must accept as the sufficient justifying condition for his having the generic rights, namely, that he is a prospective agent who has purposes he wants to fulfill. Suppose some agent A were to hold that [they have] these rights only for some more restrictive necessary and sufficient reason. This would entail that in lacking R [s]he would lack the generic rights. But if A were to accept this conclusion, that he may not have the generic rights, [they] would contradict himself. For we saw above that it is necessarily true of every agent that he must hold or accept at least implicitly that [they have] rights to freedom and well-being. Hence, A would be in the position of both affirming and denying that he has the generic rights: affirming it because [they are] an agent, denying it because [they lack] R. To avoid this contradiction, every agent must hold that being a prospective purposive agent is a sufficient reason or condition for having the generic rights. Because of this sufficient reason, every agent[s], on pain of self-contradiction, must also accept the generalization that all prospective purposive agents have the generic rights. This generalization is an application of the logical principle of universalizability: if some predicate P belongs to some subject S because S has the quality Q where the "because" is that of sufficient reason or condition), then it logically follows that every subject that has Q has P. If any agent A were to deny or refuse to accept this [for] generalization in the case of any other prospective purposive agent, A would contradict himself. For [s]he would be in the position of saying that being a[n] prospective purposive agent both is and is not a sufficient justifying condition for having the generic rights. Hence, on pain of self-contradiction, every agent must accept the generalization that all prospective purposive agents have the generic rights. Thus we have now arrived at the basis of human rights. For the generic rights to freedom and well-being are moral rights, since they require of every agent that he take favorable account of the most important interests of all other prospective agents, namely, the interests grounded in their needs for the necessary conditions of agency. And these generic rights are also human rights, since every human being is an actual, prospective, or potential agent. I shall discuss the distribution of these rights among humans more fully below. But first I must also establish that the generic rights are human rights in the further respect indicated above, namely, that they are grounded in or justified by a valid moral criterion or principle.
If the rights to freedom and well being exist only under certain conditions, lacking those conditions would mean lacking rights but the framework established an agent must always view themselves as having these rights — any restrictive condition on other people’s rights is incoherent. Being an agent generates these rights rather than a particular agent.
[This framework originally and generously contributed by Torrey Pines VB.]