My last posting on Allison concentrated on how, in Chapter 9 of his commentary on the Groundwork, Allison discusses the question of the relationship between the formulas of the categorical imperative, and, particularly, some questions that arise from his view that there is a second formula of universal law that emerges subsequent to the formula of autonomy. In this posting I am going to continue to look at the discussion of formulas of the categorical imperative in Chapter 9, focusing now on how Allison treats the question of their alleged equivalence.
The question of their equivalence is one that is approached by Allison initially in terms of extensional equivalence, which would involve the claim that the distinct formulas would yield the same results for the same cases. This is distinct from an intensional equivalence claim which would, by contrast, entail that the reason for the sameness of results would be because each of the formulas has the same fundamental rationale. The question of extensional equivalence is complicated by the problems of alleged counter-examples to the formulas, which, in the case of the formula of the law of nature, are generally false positives which are, on Allison's reading, not applicable to the Formula of Humanity. Since Allison's solution was to treat these two formulas as yielding different kinds of universality it appears difficult to see how, on his interpretation, a thesis of extensional equivalence of the formulas can be sustained.
In response Allison ventures what he terms a "complete construction interpretation" of the categorical imperative which suggests that the different formulas are parts of the construction involved in arriving at the full sense of the categorical imperative. So, for example, the formula of universal law is not treated on this view as settled by its initial statement since Kant's later treatment is taken to enrich it. Each of the formulas is taken by Allison as presenting a vantage upon the categorical imperative. The claim that the formula of universal law is "equivalent" to the formula of humanity is understood as a claim about the reconstructed formula of universality that Allison takes to have followed from the statement of the formula of autonomy. The second, enlarged, sense of universalisability is related to as one that requires endorsement by any rational being and thus to be equivalent to taking rational beings as ends-in-themselves. However, it is also the case that this interpretation takes the fuller sense of Kant's reference to a universal law of nature to be one that requires understanding these laws as teleological.
Allison contrasts his account with that of Onora O'Neill who, in contrast to Allison, has argued not merely for extensional equivalence of the formulas but also for their intensional equivalence. O'Neill's interpretation takes the force of the formula of universal law to concern the conditions of agency at work in willing and thus argues that maxims that are ruled out by it are maxims that undercut such conditions of agency. However, O'Neill does take the "perspective" of the formulas of universal law and of humanity to be distinct. On O'Neill's view the formula of universal law is a formula from the perspective of agents who acknowledge that others are also agents and requires maxims to be adopted that relate to this recognition. By contrast, on her view, the formula of humanity involves the recognition that actions affect others and thus requires us to adopt maxims that will regulate actions with this in mind. Allison points out that O'Neill's account fails to address the formula of the law of nature, which is peculiar given that this formula is the one applied to consideration of maxims.
Allison's account, based as it is on his "complete construction" hypothesis, views the earlier formulas as more "primitive" than the later and in taking this tack rules out the possibility of intensional equivalence that O'Neill's interpretation is aimed at salvaging. Whilst this attempt on O'Neill's part is certainly an interesting element of her interpretation, the view of different "perspectives" she builds in can only involve the claim that the "same" reasons are involved in a very thin sense of "same". Allison's rejection of the view that autonomy can be involved prior to being directly stated does not seem plausible to me, not least because of the appearance of claims about respect as early as the Groundwork I discussion of universal law. Whilst there is something to be said about formulas being either explicit or implicit in their appeal to autonomy I don't agree with the reading that takes autonomy not to be involved in the earlier formulas.