In my last posting on Allison I looked at the discussion he provides in his commentary on the Groundwork of the "derivation" of Kant's Formula of Autonomy. In this posting I am going to look at the second part of Allison's discussion which focuses on the relations between Kant's formulas of the categorical imperative as these follow the initial statement Kant makes of the Formula of Autonomy.
At Ak. 4: 436 Kant describes three ways of representing the principle of morality as being "fundamentally only so many formulas of the very same law" and also states that one of the formulas in question unites the other two in itself. The claim that the three formulas are all variants on the same law is termed by Allison the "singularity thesis". A claim to this effect goes way back in Kant's lectures since he criticised Baumgarten for proposing the view that there are "many" principles in ethics, indicating that on Kant's own view there is only one true principle. However, Allison is nonetheless attentive to a claim that is added by Kant to the singularity thesis to the effect that there is a difference all the same between the formulas. The difference is one that Kant terms "subjective" rather than "objective". Kant also relates this "subjective" difference to the means by which an idea of reason can, by means of analogy, be brought nearer to intuition.
Allison indicates that he finds the reference Kant makes here to analogy to be obscure even though he recognises that it is connected to Kant's general procedure of schematizing laws (as in the typic of the Critique of Practical Reason). In explicating the reference to analogy Allison looks to the Prolegomena where cognition according to analogy is described by Kant as based on "a perfect similarity between two relations in wholly dissimilar things" (Ak. 4 357-8). Allison suggests that the different formulas of the categorical imperative represent it according to different analogies. But this is difficult for Allison who does not find the Formula of Humanity to involve either an analogy with the categorical imperative or a typic. In responding to this problem Allison suggests that if the first analogy (at work in the formula of the law of nature) represents a connection between the categorical imperative and causal laws, the second, by contrast, relates to nature as embodying a teleological order, something Allison rather loosely relates to the conception of the end-in-itself in the Formula of Humanity. Even if this were to be accepted it remains unclear how the relations between the three formulas of the categorical imperative are to be grasped in relation to the requirement of coming closer to intuition.
Allison's next move is to look at the general claim that one formula unites the other two in itself. When making this claim Kant refers to the view that every maxim contains a form, a matter and a complete determination. The form is also subsequently connected to the general claim that maxims express universality. By contrast, Allison takes the reference to complete determination to refer to the harmonization of maxims with each other through the realm of ends (which relates to his earlier claim that here nature is being treated in a teleological way). So the formula of the realm of ends is taken by Allison to be the formula that unites the other two into itself.
However the next point that arises in Allison's treatment is the claim that Kant now mentions a new formula. This is the formula, expressed at Ak. 4: 436 which is referred to by Kant as "universal" and expressed as: "act according to that maxim which can at the same time make itself into a universal law". The reason why this should be taken as a "new" formula rather than as a way of showing that the formula of universal law, correctly understood, presupposes autonomy, is not immediately obvious. This is not quite the same as the view that Allison terms the "consensus" one which takes this formula to be equivalent to the formula of universal law as it requires an understanding of the "new" formula as a product of reflection upon the formula of universal law. Allison mentions a different view of the "universal formula" which has been presented by Allen Wood who takes this formula to be equivalent to the Formula of Autonomy (which does not, of course, cut against the interpretation I have suggested). However, Wood's reason for adopting this view is an odd one since he locates the basis for the claim that the Formula of Autonomy is to be primary only in a view of "human psychology" alone.
In contrast to Wood, Allison views the formula of autonomy as requiring a second, stronger, form of universalisability (being inter- rather than intra- subjective). However, since Allison thinks the second form of universalisability is made explicit in the Formula of Humanity and yet that the Formula of Humanity does not make an explicit appeal to universalisability he provides a ground for taking the "new" universal formula to unite the formula of universal law with the formula of humanity (which, however, we saw that a moment ago Allison took the formula of the realm of ends to do).
Allison takes there to be a significant difference between the original formula of universal law and the "new" universal formula on the grounds that the first refers to "willing" universal laws whilst the second, by contrast, refers to "making" them. In making this claim he agrees with Allen Wood but Allison and Wood have quite different reasons for making the claim. Wood's view was that being able to will a maxim as a universal law provides only a test for the permissibility of the maxim and that this test really only relates to maxims taken one at a time. By contrast, on Wood's view, making maxims into universal law is concerned with our maxims viewed collectively (not individually) and requires the consistency of maxims to be taken into account. Allison, by contrast to Wood, does not take the difference to be one where one of the formulas is better than the other at tracking coherence on the grounds that a coherent combination of maxims has no obvious moral merit.
Allison distinguishes between a number of the formulas in a different way. This is in terms of viewing the formula of universal law as a "meta-formula" or second-order formula which underlies and is expressed by the distinct formulas of the law of nature, the formula of humanity and the formula of autonomy (which latter Allison now equates with that of the formula of the realm of ends). However, after making this claim Allison goes on to add that the formula of universal law is only a "skeletal" form of the concept of the categorical imperative. The fully developed form of it is rather given in the "new" universal formula and this claim leads Allison to the view that there are effectively two separate forms of the formula of universal law, the one given when the categorical imperative is first introduced and the alternative one that is arrived at now, in the aftermath of the Formula of Autonomy.
The discussion in this section is thus elaborate, as is often the case when the relationship between the formulas of the categorical imperative is in question. What has thus far been lacking is any serious inquiry into the alleged difference between the two supposedly different formulas of universal law. Assuming this difference does exist there are three questions that could be asked concerning it, which are, is the difference tantamount to ruling out their extensional equivalence, does it effect any claim there might be to intensional equivalence, and does it have any practical import in reference to the consideration of maxims?