Before we show how Midgley uses the yuck factor in a way that takes seriously the problems with rationalism without dropping the kind of intersubjectively communicable morality implied by it, it will be helpful to say some things about how Midgley conceives of those problems, and of that morality.

Midgley is a non-rationalist in our sense, in that she denies at least one of the two central theses of rationalism. She denies PT, the thesis that there is a capacity called rationality which is independent from emotions and which is uniquely able to give us an accurate picture of the objective structure of the world uncoloured by our subjective phenomenology. This, she calls the “colonial picture” (1978, 260) of rationality, wherein reason is treated as a governor imposing order over the foreign lands of emotion. Rather than viewing rationality as a “single faculty in man” (Midgley 1983, 45) separable from emotions, she considers the distinction between the two to be a purely heuristic one which does not bear out in reality. In reality, Midgley holds, emotion and rationality form a continuity. To Midgley, rationality does not impose on emotions an order external to them; rather, emotions are rational just then when they are well-organized as emotions. Rationality, understood psychologically “is the process of choosing which” (1978, 258, emphasis in the original) in a conflict of emotions or desires. Rationality, in a sense, supervenes on emotion, as that kind of emotional constitution which coheres well with reality. Accordingly, rationality is neither a single faculty, nor is it wholly detached from emotions, nor does it give us unique access to the objective structure of the world. At least not in a way that is not always coloured by our subjective affective and emotional impressions. She therefore wholeheartedly rejects PT.

At the same time, Midgley does not categorically reject the historical rationalists as straightforwardly mistaken—though she holds the strict distinction between rationality and emotion to be merely heuristic, she takes it to have had merits as far as it went, and to have been broadly correct about a number of things. Among those is the rejection of subjectivism and relativism (Midgley 1993) and the conviction that “some preferences [are] ‘more rational’ than others” (Midgley 1978, 259). In other words, rationalism did right in supporting the deeply held intuitions of universality and necessity Birondo takes to be the original impetus for adopting rationalism in the first place.

Still, Midgley’s defence of the yuck factor is explicitly a defence against the overreach of a rationalism which tries to deny disgust a productive role in moral inquiry (Midgley 2003, 105). However, in contrast to Kass, her claim is not that, in addition to rational insights about morality, we should also take seriously a second, emotional, kind of insights, which are outside of rationality’s reach. Rather, her argument is that disgust and appeals to it are not themselves irrational, nor are they a-rational. Instead, they represent “real objections that can be spelled out, made clearer, and set against other considerations” (2003, 106). When we say that something is repugnant, or that it is monstrous or unnatural, these statements do not make an appeal to some blind instinct that can be dismissed as ‘mere’ emotion; nor do they express an attitude which alone is enough to pronounce them right in calling that thing morally bad. Rather, they do something more complicated: By calling something ‘disgusting’ or ‘unnatural,’ we are employing notions which have been charged, personally and culturally, with meaning which is sometimes too complex for us to consciously express to ourselves in full in the moment. Midgley takes such statements as the conscious, high-fidelity expressions of lower-fidelity thought which in further analysis can be revealed in more detail. In the case of gene-editing, and, likely, also of excessive breeding, what people are doing when they react with outrage is, according to Midgley, that “they are objecting to attacks on the concept of species” (2003, 105). That concept of species, in turn, is one which has been charged with information and value, such as the idea that when something rests within the boundaries of a species, it tends to be able to thrive autonomously in a favorable environment. For the Belgian Blue, our repugnance may point us precisely to the breakdown of this value we associate with natural species. We cannot immediately, and on first viewing, explain: ‘This animal has been changed in a way that promises disastrous consequences if they do not have access to human intervention.’ But by expressing disgust with it, we may be already gesturing to just such a suspicion.

If the claim behind such an expression is not fully rationalizable, that is not because it points us to the hidden wisdom of Kass’ heart, but because we are finite and fallible beings. Our cognitive apparatus does not always consciously and explicitly represent to us all the consequences it may unconsciously perceive implied by a situation, based both on the immediate data of the situation and on the complex cultural baggage of the notions involved. We often have to rely on non-conscious and, in a narrow sense, pre-reflective reactions to get our best picture of the world. To say, then, ‘this is disgusting’ or ‘this goes against nature’ when you see the Belgian Blue are substantive moral claims about which “others can understand what objection they are making even if they disagree” (Midgley 2003, 106), and which are therefore capable of being examined. Such examination can happen both by reflecting on the conditions under which such an affective judgment has been produced, such as the cultural background of the notion involved in it or by looking at the judging person’s personal history, but also by examining the kind of claims which are entailed by the judgment; whether it is the case that “there is a rational, conceptual link between [repugnant actions] and their [detrimental] results” (Midgley 2003, 104), so whether, in principle, one accepts negative consequences in acting in the repugnant way.

In whichever way one chooses to evaluate reactions of repugnance, two things are clear for Midgley: first, that disgust is capable of being evaluated, both because it makes an understandable point, and because that point is, in principle, accessible to rational thought. Second, in making that evaluation, one will always make use of the cognitive apparatus within which rationality can only exist in reference to desires and emotions which are more or less in line with reality. One will never be able to step ‘outside’ the affective perspective and look at an emotion with completely dispassionate rationality. This is because rationality is not merely informed by emotions, but essentially bound up with them, as “complementary aspects of a single process” (Midgley 2003, 105). Since being rational means nothing but having a well-ordered emotional life, the notion of purely unemotional rationality is nothing but a helpful fiction to distinguish calm from passionate reasoning.

How, then, does Midgley escape the problem of the lack of intersubjective communicability which Kass suffers from? Recall that we have criticized Kass for closing off proper moral justification to the people who happen to not have the right kind of constitution which would lead them to have the right kind of emotions. Kass, we have said, thereby fails to deliver the intersubjective communicability which we expect from morality. It seems that it is a valid criticism also of Midgley, that to anyone who does not have the correct emotions, crucial moral insights are simply inaccessible, making proper moral judgments just as impossible to reliably intersubjectively communicate as it was for Kass. However, with Midgley, having the correct kind of emotional constitution is both a much more permissive limit than it is for Kass and one that is much more in line with the limits we would expect to be placed on competent moral inquirers anyway. It is more permissive because in order to have the right emotional profile necessary for making proper moral judgments, for Midgley, one does not need to have a specific kind of character or have enjoyed a specific kind of education. Midgley does not exclude those who feel no immediate disgust in the face of biological engineering as unable to ever see why they are wrong—although she does hold that they are wrong. All one requires to competently make or evaluate judgments such as ‘The existence of the Belgian Blue is grotesque—it ought not be bred!’ is to be “within the range of emotional normality” (Midgley 1978, 272). She requires only a functional human emotional apparatus which is free from serious deficiencies such as the incapability of psychopaths for proper affective empathy (1978, 271).

So, Midgley’s requirements for someone competent in making proper moral judgments is more permissive than those implied by Kass’ position, where one is either revolted by the thought of human cloning, or one is unable to properly evaluate it at all. Her requirements are also more in line with what we would expect requirements for successful moral inquiry to be; for, if one falls out of this range of emotional normality, one does not only, as with Kass’ poorly conditioned inquirer, lack the ability to grasp certain pieces of moral wisdom, but one falls out of rationality more generally. If rationality is the “process of choosing which” (Midgley 1978, 258) between competing desires and emotions, then the failure to have a broadly normal range of desires and emotions entails an inability to be rational at all. This, presumably, will be accompanied by all the moral particularities associated with non-rational beings—psychopaths would be less blameworthy for example, and it would be more acceptable to restrict their freedoms for their own good and for the protection of others. So, Midgley ends up no more exclusionary than are rationalists. Like them, she considers any rational person to be a competent moral agent capable of accessing, in principle, any grounds for moral justification. She contends, further, that this requirement of “emotional normality” is not an unusually demanding one either. Rather, the assumption of “a common mental structure with other people” is “a necessary condition of our practical condition” (Midgley 1993, 80). She goes on to say:

We do not have to assume that [others] are in any way just like us, but we do have to assume, if we are to communicate with them at all, that there is an adequate likeness in basic structure. This is part of our general assumption of inhabiting a single world which is in principle coherent and intelligible—an assumption that is needed as much for science as for morals, and is indeed the basis of all thought. (ibid.)

Here, we can again see Midgley’s commitment to objectivity (albeit a relatively weak version of it). There is a common mental structure to all agents, which enables us to access the structure of the common world in which we live, mediated by our affective responses to it. This, rightly, may evoke what we have called above rationalism’s thesis about the nature of morality, MT, that the capacity which best gives us access to the objective structure of the world is what we ought to use to arrive at moral justification. This is, in essence, the lesson we should take from Midgley: that just because we dispute the characterization of rationality which rationalists base their project on, that does not mean that we have to abandon that project wholesale. We can, as it were, still work with a tempered version of rationalism.

Midgley, then, succeeds in applying the yuck factor where Kass and arguably Prinz fail: She manages to accommodate the manifest salience of reactions of disgust in moral justificatory discourses without abandoning the upshots associated with rationalism.

What does that mean for bioethicists interested in considering the moral implications of disgust-responses? This will be the subject of the last section of this article, where we will formalize what we think is productive in Midgley’s approach, and how bioethicists can use it.