Frank Hindriks

Traditional accounts of explanation fail to illuminate the explanatory relevance of “models that are descriptively false” in the sense that the regularities they entail fail to obtain. In this paper, I propose an account of explanation, which I call ‘explanation by concretization’, that serves to explicate the explanatory relevance of such models. Starting from a highly abstract and idealized model, causal explanations of the absence of regularities are sought by adding complexity to the model or by concretizing it. Whether this process is successful depends on whether the abstractions and idealizations in the basic model succeed in isolating a mechanism, i.e. in representing how it operates when interfering factors are absent. This account is developed in the context of economics and contrasted to those of Daniel Hausman and Nancy Cartwright. I go on to provide an account of how unrealistic models can be used for providing understanding of the way mechanisms work.

Intuitions about intentional action have turned out to be sensitive to normative factors: most people say that an indifferent agent brings about an effect of her action intentionally when it is harmful, but unintentionally when it is beneficial. Joshua Knobe explains this asymmetry, which is known as ‘the Knobe effect’, in terms of the moral valence of the effect, arguing that this explanation generalizes to other asymmetries concerning notions as diverse as deciding and being free. I present an alternative explanation of the Knobe effect in terms of normative reasons. This explanation generalizes to other folk psychological notions such as deciding, but not to such notions as being free. I go on to argue, against Knobe, that offering a unified explanation of all the asymmetries he discusses is in fact undesirable

According to the increasingly popular knowledge account, assertion is governed by the rule that speech acts of that kind require knowledge of their content. Timothy Williamson has argued that this knowledge rule is the constitutive rule of assertion. It is argued here that it is not the constitutive rule of assertion in any sense of the term, as it governs only some assertions rather than all of them. A (qualified) knowledge rule can in fact be derived from the traditional analysis of assertion according to which assertion is the linguistic expression of belief. Because it is more informative, this analysis provides a better point of departure for defending the knowledge account than Williamson’s view according to which the knowledge rule is part of the analysis of assertion.

According to the expression account, assertion is the linguistic expression of belief. Given the knowledge rule of belief, this entails that knowledge is a normative requirement of sincere assertions. On this account, which is defended in Hindriks, knowledge can be a normative requirement of sincere assertions even though there is no knowledge rule that is constitutive of assertion. Ball criticizes this claim arguing that the derivation of the knowledge rule equivocates between epistemic and moral senses of obligation. In response, we resist the charge of equivocation. Ball does not, after all, demonstrate that the distinction matters in the context at issue. In addition to this, we argue that it is a virtue of the account that the knowledge rule is restricted in application to sincere assertions. The case we present to illustrate this is that of the virtuous liar who knows what he believes, and is insincere because that is the right thing to do in the situation. It makes no sense, we suggest, to criticize the liar for not knowing that which he asserts. After all, it is his moral duty to assert what he knows to be false. Furthermore, his epistemic standing is impeccable, as he knows what he believes.

Many models in economics are very unrealistic. At the same time, economists put a lot of effort into making their models more realistic. I argue that in many cases, including the Modigliani-Miller irrelevance theorem investigated in this paper, the purpose of this process of concretization is explanatory. When evaluated in combination with their assumptions, a highly unrealistic model may well be true. The purpose of relaxing an unrealistic assumption, then, need not be to move from a false model to a true one. Instead, it may be providing an explanation of some phenomenon by invoking the factor that figures in the assumption. This idea is developed in terms of the contrastive account of explanation. It is argued that economists use highly unrealistic assumptions to determine a contrast that is worth explaining. The process of concretization also motivates new explanatory questions. A high degree of explanatory power, then, may well be due to a high number of unrealistic assumptions. Thus, highly unrealistic models can be powerful explanatory engines. Key Words: concretization • explanation • explanatory power • idealization • model • Modigliani-Miller theorem • unrealistic assumption.

Skill or control is commonly regarded as a necessary condition for intentional action. This received wisdom is challenged by experiments conducted by Joshua Knobe and Thomas Nadelhoffer, which suggest that moral considerations sometimes trump considerations of skill and control. I argue that this effect (as well as the Knobe effect) can be explained in terms of the role normative reasons play in the concept of intentional action. This explanation has significant advantages over its rivals. It involves at most a conservative extension rather than a radical revision of what we tend to believe about intentional action, and it fits better with the way we conceive of the relation between intentional action and moral responsibility

Current debates in social ontology are dominated by approaches that view institutions either as rules or as equilibria of strategic games. We argue that these two approaches can be unified within an encompassing theory based on the notion of correlated equilibrium. We show that in a correlated equilibrium each player follows a regulative rule of the form ‘if X then do Y’. We then criticize Searle's claim that constitutive rules of the form ‘X counts as Y in C’ are fundamental building blocks for institutions, showing that such rules can be derived from regulative rules by introducing new institutional terms. Institutional terms are introduced for economy of thought, but are not necessary for the creation of social reality.

Recent empirical research by Joshua Knobe has uncovered two asymmetries in judgements about intentional action and moral responsibility. First, people are more inclined to say that a side effect was brought about intentionally when they regard that side effect as bad than when they regard it as good. Secondly, people are more inclined to ascribe blame to someone for bad effects than they are inclined to ascribe praise for good effects. These findings suggest that the notion of intentional action has a normative component. I propose a theory of intentional action on which one acts intentionally if one fails to be motivated to avoid a bad effect. This explains the asymmetry concerning intentional action. The praise–blame asymmetry is explained in terms of the claim that praise depends on being appropriately motivated, whereas blame does not.