Free Will and the Construction of Options
Do WE HAVE FREE WILL? WHEN PHILOSOPHERS TAKE UP
this question, they nearly always approach it from a highly abstract point of view. What mainly matters to them are basic and highly general physical features of the world. How does causation work in our universe? What sorts of physical laws does it have? A standard way to proceed is to ask whether free will is possible in a world in which the laws are fully deterministic. One group of philosophers, the compatibilists, argue that if one is careful not to confuse causation with constraint, then there is no opposition between free will and determinism. Incompatibilists deny this claim.
We believe that this metaphysical debate has reached a stalemate. There are a variety of compelling arguments on either side, but nothing decisively tips the balance in one or the other way. In any case, as we said in Chapter 6, we are not going to enter the metaphysical fray about free will here. Our interest in this chapter is on another topic, one that, as the metaphysicians are busy blasting their howitzers at each other, too often gets neglected.
Most compatibilists and incompatibilists are not free will skeptics. They think that free will is possible in our universe and ordinary, unimpaired adult human beings do in fact have it. They also, of course, agree that not all things are free. A rock certainly is not free. Neither is a fern or an ant or, more controversially perhaps, a crow or rabbit. This raises a different sort of question than the metaphysical question that is at center stage in the philosophical debate—a comparative question. Assuming, as is it is standard to do, that humans do have free will, what is it about our minds and brains that distinguishes us from simpler animals that lack it? What is the distinctive psychological basis of freedom?
A natural place to begin investigating this question is with the capacities that are involved in enabling humans to make decisions. It is useful to divide these into two types. The first type consists of construction processes that enable an agent to build an option set. This is a mentally represented set of candidate action plans and their anticipated outcomes. The second type consists of selection processes. Given an option set, these enable an agent to assign evaluative weights to the elements of this set, to say how good or bad these options are. When the evaluative weights have been assigned, whichever action plan in the option set is ranked as best is next selected for execution.
It is tempting to think that the distinctive mark of human freedom is to be found in human selection processes—somehow, humans are able to select things in a way that differs from all other creatures. A bit of reflection suggests this is not a promising approach. As we saw in Chapter 2, even relatively simple animals, such as rabbits and mice, mentally represent candidate actions (e.g., continue to forage in this bush versus move on to the next bush), and their actions reliably depend on the evaluations assigned to these actions. Recall that it is the job of the affective system to maintain and update representations of the key information—probability, confidence, absolute and relative value, discrepancies between expectation and actual outcomes, and so forth—needed to generate accurate evaluations. So there is nothing categorically distinct about human selective processes that could serve as a distinguishing basis of freedom. Indeed, selection, it would seem, just has to involve the assignment of evaluative weights to options in some way or other, followed by acting on that which is evaluated as best. This is something like a forced move; it must be how selection works in humans, mice, and even machines. So it is unlikely that we will ever find a distinctive mark of freedom by looking here.
In contrast to selective processes, few thinkers have thought much about the role of constructive processes of decision-making in enabling free will. In discussions of free will, it is standard to simply assume an agent who has a rich and varied set of options already in hand. No one asks where the options come from in the first place or how they were constructed. Our aim here is to redress some of this neglect.
We will argue that the distinctive mark of human freedom is latitude. Latitude refers to what agents have when the "size" of their option set is large. For now, we can say an agent has more latitude when the number of distinct options in the option set is larger. A bit later, we will provide a more refined account of how to understand the "size" of an option set.
Simple animals have sharply limited latitude. The candidate options they can mentally represent, and from which they can in turn select, are few and relatively fixed. At the other extreme, human agents have a truly colossal amount of latitude. Because humans are deeply prospective creatures with powerful imaginal abilities, they can build option sets that are truly vast. As a result, humans can express themselves in countless ways. This latitude for self-expression is, we argue, the best answer to the comparative question of free will. It is the distinctive psychological feature that explains why humans, but not simpler animals, are free.