OPR III.8: Deontic Reasoning

Society depends upon rules—we cannot live together successfully without some shared set of social rules. But what exactly is a rule, and how do people act upon them?Quoting Gaus, “Rules…identify certain general characteristics or properties, and issue directives for actions with these properties. A fully specified social rule identifies (i) a set of persons to whom the prescription is addressed, (ii) a property of actions, (iii) a deontic operator such that actions with that property may, must, or must not be performed and (iv) a statement of the conditions under which the connection between (ii) and (iii) is relevant.” (123)

To illustrate the import of (iv), Gaus brings up two different rules:

1.     In our school, you will not speak without first raising your hand and being called upon.

2.     In our school, you will not pull another student’s hair.

Gaus says that psychological studies indicate that though the surface grammar of these rules is the same, children understand them differently. They understand 1 as merely a conventional rule, which may or may not hold in other schools or other places. Though 2 also begins with “In our school”, they understand 2 as a moral rule, which applies in all places. So they see factor (iv)—the conditions under which the property and deontic operator are relevant—as different between these two rules.

Rules take this general form:

            “An act may/must not/must be performed by persons P in conditions C if it instantiates property T.” (125)

Conflict over rules will often arise about where to draw the line between T and not-T. For example, if there is a social rule prohibiting aggressive speech, what exactly counts as aggressive speech? For rules to serve their function (in helping us live together, to minimize costs of punishment, maximize benefits of cooperation, etc.), it is better for a society to settle on some determinate threshold.

Gaus says that philosophers tend to be skeptical of rule-following—they worry that following rules is irrational because commitment to a rule might prevent one from reaching one’s goals. (Witness, for example, how most philosophers are convinced that rule-egoism must dissolve into act-egoism, or how rule-utilitarianism must dissolve into act-utilitarianism.)

In contrast, Gaus says, psychologists see social rule following as coming to us quite naturally. Human beings develop the ability to understand and follow social rules earlier than other general reasoning abilities. Psychology shows we are very good at deontic reasoning and it quite easy for us to do. One reason for this, Gaus shows via an illustration and some psychological data, is that in social rule reasoning, we’re primarily looking for cheaters

There are many different kinds of rules (e.g., prudential rules, rules of music performance, social rules), and one might be tempted to think rules are rules, and our ability to understand and follow each of these kinds of rules all stems from a general ability to follow rules. Psychology indicates this is just not so. When we reason about social rules, we use a different part of the brain than when we reason about prudential rules or other rules. Gaus summarizes, “We have reason to suppose that our cognitive structure is such that reasoning about indicative, prudential-rule following, and social-rule following are processed in different parts of the brain, with different ties to emotional states, that humans have very different competencies in these types of reasoning which develop at different ages, and that understanding social rules is fundamentally related to cheater detection while, say, this plays no part in prudential rules.” (130) Gaus concludes that since psychology shows that these different kinds of rule-following are not one unitary phenomenon, but many different phenomena, our philosophical analysis of rules and rule-following must adjust.

Questions and Comments:

 From a psychological point of view, rules are not all one thing. We are better at and develop social-rule reasoning at an early age than other kinds of rule-based reasoning, and we use different parts of the brain to process different kinds of rules. Gaus concludes that our philosophical analysis of rule-following must account for this—we should not, from a philosophical point of view, treat rules as if they were all one kind of thing. At this point in the book, I’m not sure why this is so.

 Let me say something that might sound kind of dense. Our capacities to do different kinds of mathematics develop at different times, and it might even turn out (I have no idea, really) that different kinds of mathematical reasoning activate different parts of the brain. What impact, if any, would that have on philosophical theories of mathematics and of justified mathematical reasoning? I’m not sure.

 I read this short chapter as telling us an interesting feature of human psychology and then issuing a promissory note. The chapter first tells us what rules are and then shows us that psychologically-speaking, we process different kinds of rules differently and with different degrees of skill. The following chapters will then show us what philosophical import these psychological findings have, if any.


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One Response to OPR III.8: Deontic Reasoning

  1. “Gaus says that philosophers tend to be skeptical of rule-following—they worry that following rules is irrational because commitment to a rule might prevent one from reaching one’s goals. (Witness, for example, how most philosophers are convinced that rule-egoism must dissolve into act-egoism, or how rule-utilitarianism must dissolve into act-utilitarianism.)”

    This is the way most philosophers think. But isn’t Jerry’s criticism of Gauthier et al something like this? (J. Brennan: “He claims to have shown that individual cannot reason themselves into being devoted to such rules, because such devotion might cause them to follow rules even when doing so does not best promote their values.”)

    Suppose there are a number of outcomes associated with my actions and that I can rank them all. My rankings take into account the rules in questions, their defeasibility conditions, and so on. I can assign numbers to the rankings, and I’ll call functions that replicate the ordering by the novel term “utility function”. Now, it is important to appreciate, rules are taking into account in my rankings. I expect we’ll learn that it’d be something like irrational “rule-worship” for me to put more weight on rules than is already embedded in the values represented by my utility function (or equivalent ones). If so, then Gerry seems to accept a version of the scepticism expressed above.

    I don’t think this can be right. So I’ll keep on reading. Ignore if none of what I say makes sense.

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