Multi-modal practical reasoning
Updated: Jun 13, 2022
Suppose that you're given the choice between x and y, which are equally desirable options and you'd be happy with either one. The problem is that you:
are able to choose only one option, x or y, but not both;
prefer neither x nor y in comparison to the other; and
prefer having at least one x or y to having none.
Philosophers have termed this problem, the problem of choice without preference, or the paradox of “Buridan’s Ass” (cf. Rescher 1969). For the so-called paradox the story usually goes starts with an ass that stands equidistant between two equally appetising bales of hay. Because eating either one of the two bales of hay will satiate the ass, it is unable to decide between the two bales and the ass starves to death. Absurd consequences follow when there is a choice between two equally powerful motivations.
We could update the problem of “Buridan’s Ass” using a comparatively practical example. Suppose that Smith wants to gain a position in a law firm; more particularly, she wants to be a research assistant for one of the partners in the law firm. Smith sends her resume to two law firms, Jones and Doe. Both law firms interview her, and both firms offer her the position she seeks. Suppose that Smith lists the pros and cons for each position, and each position comes up with the same pros and same cons. She compares the compensation packages of each position, and she finds no differences in the salary and benefits for each position. Smith calculates the commute time between her house and each firm and it turns out to be exactly the same for each position. Finally, she thinks about which position would be best for her career goals. Sure enough, either position would equally well satisfy her career aspirations. Which offer should Smith accept? Should Smith accept Jones’ offer or Doe’s offer?
Current debate in practical reasoning hotly contests an answer to the following question: what inference patterns are legitimate methods of arriving at decisions or intentions to act? When theories of practical reasoning are deployed to address the kind of problem that Smith faces, however, the solution is not so clear. No theory of practical reasoning seems well equipped to handle a decision where each choice would turn out to be equally good for the person involved in making the decision. Under such circumstances it is difficult to appreciate how Smith will form an intention to act, let alone maintain it in light of newly uncovered evidence. Few of the current theories of practical rationality seem capable of helping Smith out of her predicament. This is ironic since the purpose of practical reasoning is to show what the best course of action is.
Here, I'd like to consider how to assist Smith out of her predicament by showing how a theory of practical rationality, based on Łukasiewicz’s non-classical logical calculus, may help to solve her problem. First, I will review how current theories, such as instrumentalism and Bratman’s theory of intentional planning, cannot free Smith from her quandary. Then, I will suggest how a Łukasiewicz logical system may be applied as a theory of practical rationality. Finally, I will conclude that a modified theory of practical reasoning will save Smith.
Practical reasoning tells us how we ought to proceed, while theoretical reasoning concerns what we are to believe. Two theories of practical reasoning deserve consideration for showing Smith a way out of her problem, the intentional theories of Donald Davidson (2001) and Michael Bratman (1999).
Michael Bratman (Bratman 1999) argues that Davidson’s theory of intention faces a pair of difficulties in dealing with the problem of “Buridan’s Ass.” The difficulties are the result of an overly weak conception of the role of intentions and plans in practical reasoning. Davidson’s theory seems unable to accommodate the possibility of a future intention in the face of equally desirable options, and his theory cannot ensure that rational intentions are agglomerative. Even including plans, as Bratman argues, fails to solve the seemingly insoluble problem of choice without preference. Smith may plan to take the first job offered to him, but she still would have no reason to take that job because she sees the other job, i.e., the one that was not offered first, as equally desirable. So, Bratman’s theory of intentional planning fails Smith just as much as Davidson’s theory of intention fails.
Davidson’s account of an all-out desirability judgment, the crucial com- ponent in his theory of intention, is implicitly comparative. Comparisons can be either weak or strong. If Davidson’s account sees A-ing as a weak comparison, then A-ing is “at least as desirable as its alternatives.” If Davidson’s account sees A-ing as a strong comparison, then A-ing is “strictly more desirable than its alternatives” (Bratman 1999, 219). The question becomes: which type of comparison does his theory of intention require?
If Davidson’s theory requires for future intentions the weaker type of comparison, then Smith both intends to work for Jones and intends to work for Doe. Since Smith knows that she cannot work for both firms, this account is incorrect. On Davidson’s view, it seems that Smith can intend to work for Jones and intend to work for Doe without, at the same time, intending both to work for Jones and Doe. Davidson’s account violates a natural constraint that rational intentions should be agglomerative, the belief that an agent may intend to A and B (collectively) if an agent intends to A and intends to B (individually). So, Davidson’s theory cannot require for future intentions the weaker type of comparison.
This leaves the stronger type of comparison as a requirement. Smith can decide which firm to work for, but continue to see each option as equally desirable. For Smith to decide to work for Jones even though she does not judge all-out that so acting would be strictly more desirable, the intention prescribed by Davidson’s theory fails to satisfy the demands of a strong comparative evaluation.
Davidson attempts to extend the materials present in his account of intentional action to an account for future intentions, but this is a thin con- ception of the role of intention because a theory of future intention must explain why we bother to form them. Bratman believes forming future in- tentions is a part of larger plans whose role is to aid coordination of our activities over time. Future intentions require the formation of further in- tentions and constrain the formation of other intentions. This means that future intentions play a crucial role in the “on-going creation and adjust- ment of our plans,” (Bratman 1999, 233) which is exactly what Davidson neglects in his theory.
Bratman’s analysis implies that Davidson has placed restrictions on what may reasonably be considered in forming future intentions (Bratman 1999, 217-219 and 222-224). Davidson, however, never restricts his theory in the way Bratman suggests. Textual evidence shows that Davidson (2001) leaves room for the role of plans as a part of a theory of future intention. An all-out judgment should take account of all an agent’s relevant beliefs and desires.
A present intention with respect to the future is in itself like an interim report; given what I now know and believe, here is my judgment of what kind of action is desirable... My intention is based on my present view of the situation; there is no reason in general why I should act as I now intend if my present view turns out to be wrong. (Davidson 2001, p. 100)
A rational judgment will enlist all of the agent’s relevant desires, including plans. Davidson’s theory, thus, takes into consideration the role of plans, even though he does not explicitly set out a theory of intentional planning. What remains an open question is whether taking account of plans is able to solve the problem of choice without preference.
Bratman thinks the use of plans avoids the problem of choice without preference, and he believes that reason says an agent is able to choose either option. Smith can form the intention to work for Jones, even though Smith does not see working for Jones as more desirable as working for Doe. Once Smith has formed the intention to work for Jones, Smith will accept ceteris paribus Jones’s offer because intentions are conduct-controlling pro-attitudes. Conduct controlling pro-attitudes are different than desires because they include plans which do not merely influence an agent’s conduct, but control it (Bratman 1983, 273).
Davidson’s theory cannot account for intentions in the same way because he fails to recognize intentions as conduct controlling pro-attitudes. Davidson believes intentions are all things considered judgments (Bratman 1983, p. 273), which are conduct-influencing pro-attitudes that merely influence but do not control the way one acts. While it is possible to have two all things considered judgments of the form “C is all things considered optimal” and “D is all things considered optimal,” it is impossible to have both of the fol- lowing conduct controlling pro-attitudes: “I will C (which means I cannot D)” and “I will D (which means I cannot C).” All things considered judgments do not prevent an agent from holding two equally desirable intentions, while conduct controlling pro-attitudes do.
Plans may not solve Smith’s problem. Smith may settle for Jones’s offer and actually go to work for Jones, but since Smith judges any act of working for Jones is just as desirable as any act of working for Doe there is no motivation for Smith to work for Jones. No plan seems able to get around the question: how can you rationally choose one option when both are equally desirable? If we “settle in advance on one of several options judged equally desirable,” the decision does not show why the choice is the correct one (Bratman 1999, 224). Just deciding fails to satisfy the normative constraints of Bratman’s theory. Plans circumvent the problem rather than actually offering an answer to it. Accounting for plans, as Bratman’s theory does, cannot escape the problem of choice without preference.
Neither Bratman nor Davidson seems to provide sufficient means for a resolution of Smith’s problem. First, Davidson’s theory violates a natural constraint on rational intentions, the notion of agglomerativity. It should be possible for a rational agent to intend a and b together if she intends to a and if she intends to b, individually. Smith, however, cannot intend to work for both Jones and Doe without acquiring the responsibilities of the positions in both law firms. A consequence of these additional responsibilities is that Smith has contradictory intentions. For example, Smith wants more free time to spend with her family, but taking the two jobs offered her would force Smith to work much more; so, she would spend her free time working. The result is that Smith cannot intend to work for both Jones and Smith. Thus, her intentions violate the natural constraint of agglomerativity.
Second, Bratman’s theory of intentional planning fails to free Smith from her predicament because planning does not help her avoid deliberation at the time of action or aid in the coordination of her plans over time. Intentional planning requires Smith to decide between the two positions without having a predominant reason for choosing that particular position. Both positions are equally desirable, and the compensation packages are identical. The presumption is that if Smith prefers having at least one job to having none, then she would rather have a job. If both positions are equally worthy jobs and she cannot possibly work for both firms, then she does not want to have both of them. Since Smith does not prefer one job to the other and she knows that the positions have identical compensation packages, it follows that she not act on any plan to accept Jones or Doe’s offer.
Davidson’s theory is too broad while Bratman’s theory is too narrow. Other theories of intention are just as harmful to Smith as the intentional theories of Davidson and Bratman. Satisficing tells Smith to choose the position that is “good enough” for her. The problem is that both positions are “good enough.” Satisficing implies that Smith choose one option that she thinks is “good enough,” but satisficing fails Smith because she knows that both positions are “good enough.” Thus, Smith is well-advised to abandon satisficing. Since all of the intentional theories investigated here fail Smith (miserably), it seems like a good idea to construct a different option Smith may use to remove her from the quandary.
Before introducing another theory, there are some objections that deserve attention. Defenders of one of the views above might object that there is no reason to construct another theory. They may argue that a causal theory of intention, intentional planning, and satisficing are capable of freeing Smith from her predicament. Constructing another theory is superfluous. If a theory is superfluous, then there is no need for it. So, there is no need for another theory. This is to suppose that all the best theories are already available. Not all the theories are able to accommodate particular actions. Since the defenders’ theories fail Smith, there is good reason to seek alternative conceptions of intentional theories.
Given that there does seem to be some need for another theory, defenders also might object that introducing a new intentional theory is useless. The point of practical reasoning is to tell Smith which course of action is optimal for her to perform. If the theory is silent with regards to Smith’s decision, then the intentional theory is useless. So, it must be rejected. Since the theories investigated above cannot assist Smith in her decision to act, they must be rejected. Introducing another theory is useful. The new theory will end Smith’s paradoxical situation, which is more than can be said for the other theories.
Many-valued logic offers an alternative to the traditional 2-valued clas- sical system of logic. Instead of having just one system of 2-valued logic, many-valued logics entail a logical system with as many values as the alter- native conception may accommodate. The best example of a 3-valued logic is Łukasiewicz’ssystem.
Łukasiewicz’s system introduced a third truth-value, which he read as ‘indeterminate’ or ‘possible’. This third value was to be taken by future contingent statements, which he thought, following Aristotle, could not be either true or false. If a future contingent statement were true or false, then it is either necessary or impossible that the proposition is true. The only way to avoid this fatalist conclusion, Łukasiewicz urges, is to deny that future-tense contingent statements are either true or false in advance of the event.
Analogously, Smith has to avoid attributing his desires to both potential employers. So, she must refrain from desiring either job. She is not deciding not to desire both jobs, but she desires not to desire either job for the moment. If she desires one of the jobs over the other, which is irrational because they are both equally desirable, then she finds herself in the middle of a quandary. If she refrains from desiring any of the jobs, then she has a better chance of resolving the problem of choice without preference.
This is not to say that Smith does not want a job. The only thing that follows is that she does not want one job in comparison to the other. She finds her particular options equally valuable, so she cannot decide to take one job over the other because she wants that particular job. It is up to a modified theory of intention to show Smith which action she ought to perform.
An adequate resolution of the problem will require extending Bratman and Davidson’s theories of intention, offering a solution reminiscent of the way Łukasiewicz handled future contingent statements and classical logic. This resolution will include the employment of unfamiliar terminology. There needs to be a distinction between choosing, picking, and selection (Ullman-Margalit and Morgenbesser 1977). First, choosing among alterna- tives occurs when the act of taking or doing one of the actions is determined by the differences in the agent’s preferences over them. Second, when an agent is strictly indifferent with regard to the alternatives, the act of taking or doing one of them is an act of picking. Finally, selection is meant as a generic term, neutral with respect to choosing and picking.
We encounter choosing situations all the time. For example, Kathy may prefer to go to the movies more than going to the park. Kathy has a clear preference for going to the movies. These are the less interesting situations since Kathy has a clear preference of one action over another. The more interesting situations occur in cases like Smith’s, which is described above. In this type of situation, Smith has no clear preference because her preference is thoroughly symmetrical.
From Smith’s dilemma arise simple picking situations. Smith cannot select both jobs and she is indifferent between working for Jones and working for Doe. She prefers the selection of one whichever it may be to the selection of none. This is an accurate characterization of a picking situation, but what remains is how to rationally defend Smith’s picking one job over the other.
To rationally defend Smith’s picking one job over the other is to dis- tinguish between two different types of rational intention, what I will term general intentions and specific intentions. General intentions refer to those initial pro-attitudes in favor of actions in so far as they are of a certain type. For instance, Smith has the general intention of securing a job. General intentions refer to broad descriptions of future actions. Specific intentions refer to pro-attitudes as a property of particular actions. For example, Smith has a more specific intention in favor of securing a research assistant position for a prominent law firm. Specific intentions run the risk of not permitting the agent to follow through with action. This is a risk that the agent must take and one that may also occur at a general level, i.e., a job may not be available at any prominent law firm, there may not be any prominent law firms in town, or Smith may be the victim of a horrible accident on her way to interview at one of the prominent law firms. Regardless, general and specific intentions are representative of what Davidson termed all things considered judgments. They are not necessarily conduct controlling pro-attitudes, but they certainly influence the way an agent acts.
Having distinguished between general and specific intentions, we now must show how these intentions assist in the execution of future action. Similar to Bratman’s theory of intention, there is a certain amount of planning involved. As Bratman has said, “we do not simply act from moment to moment” (Bratman 2000, p. 40). Rational agents settle in advance on future- directed plans of action. These plans of action play a basic role in support of the organization and coordination of our activities over time. Essentially, “plans provide a somewhat stable background framework that needs to be filled in appropriately with specifications of means and the like” (Bratman 2000, p. 41).
In terms of Smith’s dilemma, she begins with a plan of action that in- cludes a general intention to secure a job. She then plans a course of action consistent with her specific intention to seek a research assistant position with a prominent law firm. This is a choosing situation since it was Smith’s preferential desire to seek a research postion over a receptionist position or some other job that may be available. Smith possesses a conduct influencing pro-attitude in favor of seeking a job. When she interviews for a number of identical jobs and she is offered both of them, Smith merely needs to pick one because all of them will presumably satisfy her desire for a job. There is no need to abandon her original plan since the content of that plan was general. Smith may pick any one of the jobs, either the position at the Jones law firm or the position at the Doe law firm.
What I have tried to show is that we can overcome the problem of choice without preference if we settle on a theory of intention that synthesizes Bratman’s notion of intentional planning with Davidson’s causal theory of action. By distinguishing between general and specific intentions, the agent may form future intentions without worrying that such intentions will be rendered inoperable at the time of action. Also, the agent should modify plans that accord with her general and specific intentions. In this way, if the agent ever has to face a situation like Smith’s dilemma, then the agent will know that she will not suffer the same fate as Buridan’s ass.