Dougherty focuses on cases in which a person agrees to sex as a result of being deceived about a “deal-breaker”. A deal-breaker, roughly, is a fact about a person’s prospective sexual partner such that the person would not agree to sex were she to learn this fact. Since Alice would not knowingly agree to sex with a Republican, the fact that a person is a Republican is a deal-breaker for her. My aim in this section is to argue that not all deal-breakers are equal. Some are stronger than others.

An analysis of deal-breaker strength

Here is my proposal in broad outline. A deal-breaker, in Dougherty’s words, is “a feature of the sexual encounter to which the other person’s will is opposed” (Dougherty 2013, 719). But opposition is a matter of degree: a person’s will may more strongly oppose some features than others. The strength of opposition may be revealed in situations of uncertainty or risk, where the feature is not known either to be present or absent. We may then see how great a risk of choosing an option with this feature the person is willing to take. The greater is this risk, the weaker is her opposition, and hence the weaker is her deal-breaker.

Consider, for example, deal-breakers in a different context. For a vegan, the fact that a meal contains animal products is a deal-breaker with respect to eating it. A vegan is someone who would not knowingly consume animal products. But some vegans are more commited than others. Imagine two vegans, Fiona and Michael. One day, they visit their friend, Hugh, who has prepared a meal for them. Being somewhat absent-minded, however, Hugh is not sure whether he made his pasta with vegan pesto. “I’m pretty sure it said ‘vegan’ on the jar,” he says with little conviction. Michael is not deterred: “That’s good enough for me,” he says as he tucks in. But Fiona is more cautious: “Well, if you’re not certain, then I’d rather not take the risk.” Assume that, were there no doubt as to the vegan-friendliness of the meal, Fiona and Michael would be equally eager to consume it. They are equally hungry, equally fond of Hugh’s cooking, and so on.

We may infer from their choices that Fiona is the more committed vegan. Her will opposes the consumption of animal products more strongly than Michael’s does. Notice, however, the difference between Fiona and Michael is not whether the presence of animal products is a deal-breaker. Michael, like Fiona, would not eat Hugh’s pasta if he knew it contained animal products.Footnote 1 The difference, rather, is that in situations such as this, where they do not know either way, Michael is prepared to risk eating animal products, but Fiona is not. It seems quite natural to say, therefore, that this is a greater deal-breaker for Fiona than for Michael.

Using the tools of decision theory, we may define a measure of deal-breaker strength along these lines. We can ask how great a risk of eating animal products a person will take. The greater is this risk, the smaller is the deal breaker. The decision in the above example can be represented as follows:

Actions States Non-vegan (p) Vegan ( \(1-p\) ) Eat Satisfied & Immoral Satisfied & Moral Don’t eat Unsatisfied & Moral Unsatisfied & Moral

There are two possible states of the world: either the food is non-vegan (i.e., containing animal products), or it is vegan. Let the probability of the former be p, and the latter \((1-p)\). The agent may choose either to eat the food or not. The outcome of each action in each state is shown in the table. If the agent chooses to eat the food and it is non-vegan, then her hunger will be satisfied, but she will have acted immorally, by the ethical standards of veganism. (Assume she is a vegan on ethical grounds.) If she chooses to eat the food and it is vegan, then she will be both satisfied and moral. Finally, if she chooses not to eat the food, then she will be unsatisfied but moral in either case. (Assume there is no other food to eat.)

Let us write S for satisfied and M for moral. The presence of animal products is a deal-breaker for the agent if she prefers \(S \& M\) to \(\lnot S \& M\), and prefers \(\lnot S \& M\) to \(S \& \lnot M\). If she is certain the food is non-vegan (\(p = 1\)), then she prefers not to eat it; but if she is certain the food is vegan (\(p = 0\)), her preference is reversed.

We may then consider intermediate cases, where \(0< p < 1\). These are cases of uncertainty or risk. We may assume that increasing the value of p will reduce the agent’s inclination to eat the food. That is, if she prefers to eat the food for some value of p, then she will also prefer this for any lower value. We may then ask what is the maximum value of p for which she prefers to eat the food (or, more precisely, what is the least upper bound of the values of p for which this holds). The greater is this maximum value, the smaller is the deal-breaker. Fiona’s maximum, for example, is lower than Michael’s.

Suppose the agent’s preferences are represented by an expectational utility function U. Then the strength of her deal-breaker is given by the ratio:

$$\begin{aligned} \frac{U(\lnot S \& M) - U(S \& \lnot M)}{U(S \& M) - U(S \& \lnot M)} \end{aligned}$$

The greater is this ratio, the smaller is the risk she is willing to take, and hence the stronger is her deal-breaker. To illustrate, suppose Fiona’s and Michael’s utilities are as shown in the following table:

Utility Deal-breaker \(S \& M\) \(\lnot S \& M\) \(S \& \lnot M\) strength Fiona 12 10 2 0.8 Michael 16 4 1 0.2

Fiona and Michael do not differ with respect to the order of the three outcomes: both say \(S \& M\) is best, \(S \& \lnot M\) is worst, and \(\lnot S \& M\) is in the middle. The presence of animal products is thus at least a weak deal-breaker for both. Their wills oppose the consumption of animal products to at least some degree. However, they differ with respect to the location of the middle option vis-à-viz the other two: Fiona has it closer to the top; Michael has it closer to the bottom.Footnote 2 (A more general definition of this measure is given in the “Appendix”.)

This provides a precise numerical measure of deal-breaker strength on a ratio scale. It enables us to say, for example, than one deal-breaker is twice as strong as another. However, the measure rests on assumptions that may be controversial. It assumes, in particular, that a person’s “will” is aptly represented by her preferences over “lotteries”. In the above example, the agents’ preferences over lotteries involving some risk of consuming animal products are taken to show how much veganism matters to these agents. One reason to doubt this is that it is insensitive to the agents’ general attitudes to risk. If Michael is a thrill-seeker who likes to live life on the edge, whereas Fiona is more conservative, then Michael’s greater preparedness to risk eating animal products might not show that veganism matters less to him.

I am unsure what to say about risk aversion in this context. It does not seem obviously mistaken to say that risk-lovers generally have fewer or weaker deal-breakers than others. But if this is problematic, then the measure might be modified to avoid this implication. When we compare two agents with the same level of general risk aversion (or we are comparing a single agent in two different situations), the measure would remain as above. But in other cases, we might apply a variable “discount rate” to the agent’s utilities which would correct for differences in general risk aversion.

Still, even if such a modification could deal adequately with risk aversion, some may object, more broadly, that the decision-theoretic approach taken here is misguided. A person’s will is better understood in terms of the ordinary notion of desire, rather than the technical notion of preference employed by decision theorists and economists. When we say, for example, that veganism matters more to Fiona, we simply mean that she has a stronger desire to avoid eating animal products. This is easily comprehended without the need for utility functions and the like.Footnote 3 This objection raises important issues about the psychology of desires and preferences which are beyond the scope of this essay. I should emphasise, however, that the measure of deal-breaker strength I have proposed is separable from the more general analysis of such strength on which it is based. This analysis says merely that, as a deal-breaker is a feature to which a person’s will is opposed, the strength of a deal-breaker correspondingly varies with the strength of the will’s opposition. Precisely how one elaborates this notion of a person’s will opposing a feature is a further issue. I have suggested one way of doing this, in decision-theoretic terms. A nice feature of this approach is that provides a way to define a measure of deal-breaker strength. But this is inessential for my argument. The essential point is merely that deal-breakers vary in strength.

A final note of clarification. On the analysis I am offering, certain patterns of preferences are what determine the strength of a deal-breaker; they are not mere evidence that the deal-breaker has a certain strength. Nonetheless, there is an important epistemic element in the overall account. We cannot directly observe a person’s preferences, and therefore, on this account, we cannot directly observe her deal-breakers. Rather, we infer a person’s preferences, at least in part, from her observed choice behaviour. When Fiona chooses not to eat the pasta, this reveals to us something about her preferences, and thereby something about her deal-breakers. I return to this issue below when discussing the question of wrongness in our two cases of deceiving into sex.

An alternative analysis

Before continuing, I would like to compare the analysis proposed above with a similar one suggested by Neil Manson, which also distinguishes stronger and weaker deal-breakers. The extent to which these analyses are incompatible is not entirely clear. But in any case, as I argue below, my proposal seems preferable, because it offers a deeper explanation.

Manson explains his analysis as follows:

The gradable voluntariness theory takes into account the fact that some kinds of deception may merely tip the balance in favor of deciding to consent. Where deception tips the balance, the relevant counterfactual—if R were to know that p she would not consent—is true, but the counterfactual is only made true by a relatively small set of very close possible worlds. Suppose R wouldn’t want to have sex with older men. S, aware of this, dyes his hair to appear younger. Suppose R finds S attractive, witty, sexy. R willingly has sex with S. There are some close possible worlds where R knows the facts about S’s age and does not consent. But there are also close possible worlds where R knows the facts and does consent (she might, e.g., revise her extant preferences in light of new information: “Who knew? Not all old guys are monsters!”). But deception can also lead the consenter to make a never-in-a-million-years type of decision. Suppose S deceives a devoutly religious R—who would rather die than have sex with a person outside her religion—into having sex, by lying about his religion. Even if R has other reasons for consenting to sex with S, there are no close possible worlds where R knows the truth about S’s religion and R consents. In this example, unlike the one above, we have a fantastically strong deal breaker. (Manson 2016, 419)

Suppose some fact F is a deal-breaker for R. To evaluate its strength, on Manson’s account, we move from the actual world to the “closest” possible world where F is not a deal-breaker for R. The greater the distance we must travel, through modal space, the stronger is the deal-breaker. This raises two questions. First, when surveying other possible worlds, which facts must be held fixed and which are allowed to vary? Second, how do we measure similarity, or “closeness”, between worlds? Though Manson does not explicitly supply these details, his parenthetical comment—“she might, e.g., revise her extant preferences”—suggests the following. The facts which are held fixed are those about the objects of R’s preferences (e.g., facts about S, in Manson’s example), and the facts which are allowed to vary are those about R’s preferences. The relevant measure of similarity, then, is between preferences. The question is: holding fixed the other facts, how great a change in R’s preferences would be required for F to cease being a deal-breaker for R?Footnote 4

This raises the question of how to measure similarity between preference relations. Perhaps the simplest approach is to count the number of common pairs. For example, let \(\succsim\) and \(\succsim ^*\) be preference relations on a set of options X. Then we may consider the cardinality of their intersection, i.e., of the set \(\{ \langle {x, y} \rangle \in X^2 : x \succsim y \wedge x \succsim ^* y\}\). The larger this set, the greater the similarity between the preference relations. It is unclear, however, whether this will deliver the result Manson wants in his two scenarios, i.e., that there is greater preference change in the “age” case than in the “religion” case. In either case, merely reversing R’s preference over a single pair of options (i.e., having sex with S, and not doing so) may be sufficient for the relevant fact to cease being a deal-breaker. So this simple cardinality measure seems inadequate for Manson’s purposes.

Rather, Manson seems to assume a measure of preference change that takes into account similarity between the objects of preferences. Such a measure may be fairly intuitive. For example, suppose I prefer beer to wine, and, among beers, I prefer ale to lager. Now consider two possible changes in my preferences. In the first, I continue to prefer beer to wine, but I reverse my preference regarding ale and lager. In the second, I continue to prefer ale to lager, but I reverse my preference regarding beer and wine. It seems natural to say that the latter change is greater. A plausible explanation is that ale is more similar to lager than beer is to wine.

In Manson’s first scenario, the relevant preference change involves R’s preferences regarding older and younger men, whereas in the second scenario, it involves R’s preferences regarding, say, Christians and non-Christians. It might be said that, because there is in general more similarity between older men and younger men than there is between Christians and non-Christians, the latter preference change is greater, as required by Manson’s analysis.

However, it is doubtful that this analysis will work in cases like that of Fiona and Michael above. In this case, the relevant preference change seems the same for Fiona and Michael. For both of them, the preference change involves their preferences regarding vegan food and non-vegan food. Whatever the degree of similarity between vegan food and non-vegan food, this will be the same for Fiona and Michael. Yet, as I said above, it is plausible that Fiona’s deal-breaker is stronger. It is unclear, therefore, whether Manson’s analysis can give a satisfactory explanation of this case.

In any event, I think there is a good reason to prefer an analysis like the one I have proposed to Manson’s alternative. Suppose, for argument’s sake, that there is a difference in the “size” of preference change required for the presence of non-vegan ingredients to cease being a deal-breaker for Fiona and Michael. Presumably, if this is so, then it is due to some underlying difference in Fiona’s and Michael’s actual preferences. A deeper explanation, therefore, will be one which identifies what this actual difference may be. This is what my proposal attempts to do. It explains the difference in deal-breaker strength between Fiona and Michael in terms of the their actual preferences. Now, it might be the case that, given this difference in their actual preferences, the size of preference change required for Fiona is greater than that required for Michael, in which case Manson’s analysis may agree with mine. But then mine would seem to give the deeper explanation. On the other hand, if the two analyses do not agree, then mine seems more plausible.

Local versus global deal-breakers

The analysis above concerns what might be called “local” deal-breakers. It concerns the extent to which a property is a deal-breaker in particular circumstances. This might vary in different circumstances. Fiona might be more willing to risk eating Hugh’s pasta were she very hungry; Michael might be less willing to do so were Hugh known to be a bad cook. This might not sit well with our ordinary notion of a “deal-breaker”. We normally think of deal-breakers as being more robust, not so sensitive to such changes in circumstances. It would be absurd to say, for example, “I’m a vegan, but only when I’m not hungry.”

To better capture the ordinary notion, we may also consider a “global” dimension of deal-breaking strength. A property might be a (local) deal-breaker in one situation but not in another. We may thus think of its global strength as determined by how broad or narrow is the range of situations in which it is a deal-breaker. A maximally strong global deal-breaker—call it a “fundamental” deal-breaker—is a local deal-breaker in all possible situations. Presumably, the presence of animal products is not a fundamental deal-breaker even for most vegans. Few, I assume, would starve to death rather than compromise their vegan scruples, for example. We may be sceptical about the existence of any fundamental deal-breakers. We may believe that “everyone has a price”. For example, most people say they would never eat human flesh, yet there are well-known cases of ordinary people resorting to cannibalism in extreme circumstances.

Among non-fundamental global deal-breakers, we may distinguish weaker and stronger: X is globally at least as strong as Y if and only if every situation in which Y is a deal-breaker is also a situation in which X is a deal-breaker, i.e., \(D_X \supseteq D_Y\), where \(D_X\) and \(D_Y\) are the sets of situations in which, respectively, X and Y are deal-breakers. For example, the presence of meat may be for many vegans a stronger deal-breaker than the presence of animal products. If a person would not choose to eat animal products in a given situation, then a fortiori she would not choose to eat meat in the same situation. However, there may be situations in which, though she would not choose to eat meat, she would choose to eat, say, cheese. Notice, this gives us only a partial ordering of deal-breakers. In some cases, it may be that neither \(D_X \supseteq D_Y\) nor \(D_X \subseteq D_Y\) holds. In such cases, we may want to compare the relative size of \(D_X\) and \(D_Y\), but this will be difficult if, as seems likely, \(D_X\) and \(D_Y\) are both infinite.

As I say, this global definition may be closer to our ordinary notion. In what follows, however, I will focus solely on local deal-breakers, since this seems closer to what Dougherty has in mind. Moreover, it may be argued that, from the standpoint of moral evaluation, local deal-breakers are more relevant, since the moral evaluation of an action should attend to the particular features of the context in which it occurs.