And you are told: RCTs–randomized controlled trials–will show you what these are.
That’s not so. RCTs are great, but they do not do that for you. They cannot alone
support the expectation that a policy will work for you” (Cartwright and Hardie
2012, ix).
Ex ante considerations have to use assumptions concerning the behaviour of
actors. The choice of the appropriate cognitive and motivational assumptions about
actors has an important effect on the evaluation of rule systems. In economics, actor
models are used which ascribe to the actors certain capabilities and intentions. The
economists Brennan and Buchanan, for example, argued for the use of the homoeconomicus model for the comparative evaluation of rule systems. They note
explicitly that this model does not describe empirical facts but is useful for theoretical and methodological reasons (Brennan and Buchanan 1985, 74).
But the homo-economicus model is confronted with a dilemma: If one chooses
the model for prediction and assumes that the actors comply with the rules, then one
disregards the problem that some people disobey the rules. But if one does not
assume that the actors follow the rules in the first place then one has the problem of
the rationality of being guided by rules and one cannot assume that the rule system
can exist at all. The problem of the intentional and rational rule-following of a homo
economicus was presented for example by the philosopher Edward McClennen
(2004): If rules prescribe or forbid an act in a situation, then this act is supported
by (the balance of) reasons or not, so there is no better option or there is a better
option. If the act is supported, then the rule is irrelevant. If the act is not supported,
then it would be irrational to follow the rule. So, rules are either irrelevant or it is
irrational to follow them. McClennen’s reaction on this dilemma is inter alia the
recommendation for changing the standard model of rational rule following.
The point of the last remarks is that we need theoretical assumptions about the
behaviour of actors and the different style of rule uses. But the use of an actor model
should not only be supported by methodological reasons but also by evidence
because “unrealistic assumptions [. . .] lead to untenable explanations of social
phenomena” (Anderson 2000, 200). But theorists shouldn’t use over-simplified
actor models which are blind for some kind of evidence for the ex-ante evaluation
of policies. Or to say it with Elinor Ostrom: “The embarrassment that we face is that
policy analysis has yet to develop a coherent understanding of how our subject
matter should best be expressed, how rules fit or don’t fit together to shape observable behavior and outcomes” (2005, 181).
4.3 The Specific Adequacy Criterion
The legal philosopher Herbert Hart (1994) indicated repeatedly that in a normative
system the rule agents “apply the rules themselves to themselves”. So, rules without
acceptance are either non-used (and so ineffective) or it is very expensive to ensure
the required rule use. For the evaluation of rule systems we need evidence that the
rules will be accepted. In the process of application there can occur unacceptable
118
K. C. Reinmuth
That’s not so. RCTs are great, but they do not do that for you. They cannot alone
support the expectation that a policy will work for you” (Cartwright and Hardie
2012, ix).
Ex ante considerations have to use assumptions concerning the behaviour of
actors. The choice of the appropriate cognitive and motivational assumptions about
actors has an important effect on the evaluation of rule systems. In economics, actor
models are used which ascribe to the actors certain capabilities and intentions. The
economists Brennan and Buchanan, for example, argued for the use of the homoeconomicus model for the comparative evaluation of rule systems. They note
explicitly that this model does not describe empirical facts but is useful for theoretical and methodological reasons (Brennan and Buchanan 1985, 74).
But the homo-economicus model is confronted with a dilemma: If one chooses
the model for prediction and assumes that the actors comply with the rules, then one
disregards the problem that some people disobey the rules. But if one does not
assume that the actors follow the rules in the first place then one has the problem of
the rationality of being guided by rules and one cannot assume that the rule system
can exist at all. The problem of the intentional and rational rule-following of a homo
economicus was presented for example by the philosopher Edward McClennen
(2004): If rules prescribe or forbid an act in a situation, then this act is supported
by (the balance of) reasons or not, so there is no better option or there is a better
option. If the act is supported, then the rule is irrelevant. If the act is not supported,
then it would be irrational to follow the rule. So, rules are either irrelevant or it is
irrational to follow them. McClennen’s reaction on this dilemma is inter alia the
recommendation for changing the standard model of rational rule following.
The point of the last remarks is that we need theoretical assumptions about the
behaviour of actors and the different style of rule uses. But the use of an actor model
should not only be supported by methodological reasons but also by evidence
because “unrealistic assumptions [. . .] lead to untenable explanations of social
phenomena” (Anderson 2000, 200). But theorists shouldn’t use over-simplified
actor models which are blind for some kind of evidence for the ex-ante evaluation
of policies. Or to say it with Elinor Ostrom: “The embarrassment that we face is that
policy analysis has yet to develop a coherent understanding of how our subject
matter should best be expressed, how rules fit or don’t fit together to shape observable behavior and outcomes” (2005, 181).
4.3 The Specific Adequacy Criterion
The legal philosopher Herbert Hart (1994) indicated repeatedly that in a normative
system the rule agents “apply the rules themselves to themselves”. So, rules without
acceptance are either non-used (and so ineffective) or it is very expensive to ensure
the required rule use. For the evaluation of rule systems we need evidence that the
rules will be accepted. In the process of application there can occur unacceptable
118
K. C. Reinmuth