Norms and Causal Questions

Norms and Causal Questions

Causal questions about particular events are generally raised only when these events are abnormal. The close connection between causal reasoning and norms is evident in the rules that govern the homely Why question as it is used in conversations about particular events (Lehnert, 1978). The Why question implies that a norm has been violated. Thus, the question, "Why was John angry?" indicates Q's belief that it was normal for him not to be, and the question, "Why was John not angry?" indicates the contradictory belief. Even the question, "Why is John so normal?" implies that he is normal to an abnormal degree. A Why question, then, presupposes that some state X is the case, and also implies an assertion that not-X was normal. The strongest indication of the implicit assertion of a norm is that the Why question, unlike most others, can be denied. The denial can be expressed by a question, as in the familiar exchange:

Q: "Why do you so often answer a question with a question?" A: "Why not?"

The Why not retort denies the assertion that not-X is normal. It is a legitimate answer that, if accepted, leaves nothing to be explained.

We suggest that Why questions (at least those of the deniable variety, for which "Why not?" is a sensible answer) are not requests for the explanation of the occurrence or nonoccurrence of an event. A Why question indicates that a particular event is surprising and requests the explanation of an effect, defined as a contrast between an observation and a more normal alternative. A successful explanation eliminates the state of surprise. This is commonly done in one of three ways. First, A may deny the implied assertion that X is abnormal in the light of what Q already knows. This is the Why not answer, which invites Q to change his opinion that X is abnormal. Second, A may inform Q of some fact of which Q was previously ignorant, which makes the occurrence of X normal. For example, Q may not have known that Joan used the Brown text, which he knows to be excellent. Third, A may indicate that there is a causal link, of which Q was presumably ignorant, between the effect X and some known aspect of the situation. For example, Q may know that Joan had used the Brown textbook, but he may need to be told that it is excellent.

The choice of causal feature is constrained in many ways that have been discussed extensively by philosophers (for particularly relevant treatments, see Hart & Honore, 1959; Mackie, 1974) and by psychologists (Einhorn & Hogarth, 1986; Kelley, 1967; Schustack & Sternberg, 1981). We are not concerned with the factors that determine impressions of causal efficacy; instead we focus here on a constraint that relates directly to the notion of norm: A cause must be an event that could easily have been otherwise. In particular, a cause cannot be a default value among the elements that the event X has evoked. The rule that a default value cannot be presented as a cause was noted by Hart and Honore (1959), who observed that the statement, "It was the presence of oxygen that caused the fire" makes sense only if there were reasons to view the presence of oxygen as abnormal. It is important to note, however, that a property need not be statistically unusual to serve as an explanation; it is only precluded from being a default value. Peculiar behaviors of cars observed on the road are frequently "explained" by reference to the drivers being young, elderly, or female, although these are hardly unusual cases. The default value for an automobile driver appears to be middle-age male, and driving behavior is rarely explained by it.