The Value of True Belief
When knowledge is thought of in terms of adequate information, various puzzles become less problematic, including ones related to the value of true belief and knowledge. In this chapter, I consider issues about the value of true belief, and in the next related issues about the value of knowledge.
Bernard Williams observed that belief is a psychological state that “aims” at truth. John Searle expresses the same point in terms of mind-to-world direction of fit. It is, he says, the “responsibility” of belief to match the world.1
Williams and Searle are speaking allegorically—beliefs are not the sort of things that have aims or responsibilities—but the allegories are apt. When we deliberate about what to believe, the value that usually occupies us is truth. We try to determine which beliefs would be true as opposed to which would be useful. We weigh evidence for and against a claim, but we don’t very often weigh the practical benefits and costs of believing it as opposed to not believing it.
More precisely, we don’t do so explicitly. Self-interest and other non-truth-related considerations notoriously influence beliefs, but typically not consciously. We rarely make a conscious decision to ignore or discount evidence in favor of a claim because believing it would not be in our self-interest. Deliberations about what to say are of course a very different matter. We often deliberate about whether to say what is polite, useful, or ingratiating as opposed to what is true. Not so with beliefs, however.
Why is this? What a person believes, like what she does, decides, and intends, can have important practical consequences. Yet our practice is by and large not to dwell upon them in deliberations and debates about what to believe. At first glance, this can seem puzzling.
But note, insofar as the context is one in which we are trying to persuade someone (sometimes ourselves) of something, introducing practical considerations is usually beside the point, since ordinarily they are not the kind of consideration that consciously prompts belief.
Suppose one of your goals is to be promoted, but you are skeptical of your chances. Even if I point out to you that believing you will be promoted would make you less nervous which in turn would improve your job performance, thereby making the promotion likely, this ordinarily will not be enough to prompt belief. By contrast, if I cite strong evidence indicating that you will be promoted, belief often does follow.
Deliberating about pragmatic reasons for belief is thus often pointless. It is usually also redundant. Since in general it is in one’s interest to have beliefs that are accurate and comprehensive, practical considerations tend to coincide with epistemic ones.
We all are constantly faced with an enormous number of decisions. Some are important while others are less momentous, but even the apparently minor ones, if made badly, can have the potential for disaster, for instance, whether to fasten the seatbelt for a short taxi ride. Moreover, we don’t know in advance all the decisions we are going to face and hence don’t know what information we will need in order to make them well. This would not matter if we always had ample time to gather information and deliberate, but for the most part we don’t. The sheer number of decisions confronting us means that most have to be made on the spot, without the luxury of evidence gathering, consultation, and deliberation. We are forced to draw upon our existing stock of beliefs, and if that stock is either small or inaccurate, we increase the likelihood of poor decisions.
Thus in general, the beliefs most useful to us are those that are accurate and comprehensive. By having such beliefs, we are able to fashion effective strategies for achieving our various ends. Thus, for all practical purposes, taking this phrase literally, we usually can safely restrict our attention to epistemic reasons in our deliberations about what to believe.
To be sure, it is possible to conceive of occasions where epistemic and practical reasons for belief pull in different directions. Pascal famously suggested that belief in God might be such an example, since there is a potentially huge payoff if the belief is true; but it is not difficult to dream up nontheistic examples as well, although the clearest cases again tend to be ones in which the stakes are unusually high. If you are aware that a madman will kill your children unless you come to believe, and not merely act as if you believe, that the earth is flat, you have reasons to find ways of somehow getting yourself to believe this proposition, difficult as this may be. In the vast majority of cases, however, practical considerations push us in the direction of having accurate and comprehensive beliefs. They push us, in other words, in the same direction as our epistemic reasons.
Our normal routine is thus to ignore practical considerations when we are deliberating about what to believe. They do nonetheless extensively influence our opinions. As mentioned above, they do so unconsciously, but more interesting for purposes here is that they also do so in a more calculated and rational way, albeit at one remove. They help determine what issues are worthy of investigation and how much time, energy, and resources it is appropriate to devote to investigating them.
Before starting on a long car trip, I need to decide whether to check the condition of my tires, and if so, how thoroughly to do so. Should I quickly inspect them myself? Should I take the car to a service station and have it put on a lift so that they can be examined systematically? Perhaps I should even take the time to look up the durability record for the make of tires on my car.
Similarly, if I become interested in whether fMRI machines can reliably determine whether a person is lying, I need to decide how much time to devote to looking into this. Should I be content with reading the story published in the science section of the newspaper, or should I also take the time to read the more extensive piece in the recent New Yorker, or should I go to the trouble of educating myself about how fMRI machines work?
So it is with countless other issues and questions, from what the balance is in my checking account and what risks are associated with the medication I am taking to which regions of the world have the greatest population growth. I cannot gather evidence and deliberate about every issue that confronts or interests me, much less conduct a thorough inquiry into each. There are too many issues, and my time and capacities are limited. Choices have to be made, and making them well is a matter of gauging how important it is for me to have accurate and comprehensive beliefs about the matter in question. As the stakes go up, so too should my efforts. If it is more important for me to have accurate and comprehensive opinions about P than Q, and if the prospects of successful inquiry are about the same for each, it is reasonable for me to devote more time, energy, and resources to investigating and thinking about P than Q. If I then do so, I am likely to have more extensive and detailed information about P than Q, which in turn shapes what I believe, and what it is rational for me to believe, about each.
Pragmatists in the tradition of James and Dewey sometimes remark that inquiry is or at least ought to be directed at the acquisition of beliefs that are useful. Such remarks underestimate the role of curiosity-driven inquiry, but on the other hand there is often something askance about acquiring truths for their own sake. To return to an example mentioned earlier, if someone spends most of his waking hours going to the houses of friends and counting the number of grains in their saltshakers, he is acquiring truths the rest of us lack, but his project is ill conceived and even disturbing, because it is at odds with a well-ordered life. The value of the information he is acquiring is not commensurate with the time and effort he is expending to obtain it.
So, even if pragmatists sometimes overstate their case, they are on to something. One who counts grains of salt may be acquiring true beliefs, but it is difficult to see how he is acquiring anything of significant value.
This insight can be acknowledged, however, without sliding into the view that the principal goal of deliberation and inquiry is the acquisition of useful as opposed to true beliefs. Practical considerations play a major role in determining what it is reasonable for us to believe, but they do so by helping to determine which issues are worthy of attention and the extent of evidence gathering and deliberation it is appropriate to devote to these issues. They give direction to inquiry and impose constraints on it, but once the direction and constraints are established, usefulness tends to drop out. The aim is then to determine which beliefs would be true, not which would be useful.