Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site gargoyle.UUCP Path: utzoo!watmath!clyde!cbosgd!ihnp4!gargoyle!carnes From: carnes@gargoyle.UUCP (Richard Carnes) Newsgroups: net.legal,net.politics.theory,net.auto Subject: Re: Seatbelts for passengers (micromotives & macrobehavior) Message-ID: <160@gargoyle.UUCP> Date: Mon, 19-Aug-85 20:34:49 EDT Article-I.D.: gargoyle.160 Posted: Mon Aug 19 20:34:49 1985 Date-Received: Sat, 24-Aug-85 00:25:04 EDT References: <535@brl-tgr.ARPA> <987@sphinx.UChicago.UUCP> Reply-To: carnes@gargoyle.UUCP (Richard Carnes) Followup-To: net.politics.theory,net.legal Organization: U. of Chicago, Computer Science Dept. Lines: 46 Xref: watmath net.legal:2126 net.politics.theory:969 net.auto:7744 Mitch Marks writes: >All the same, I'd like to propose another rationale in favor of the law, one >which isn't respectable enough to make it as an official reason, but which >is ultimately the real reason why I'm fer the law more than agin it. All in >all, I would rather wear a belt and be safe. But (before the law) I would >often feel silly -- like a nerdo wimp, you might say -- or else, when a >passenger, feel like I'm insulting the driver. "I'd better get this belt >on quick, 'cause I know you're gonna crash us." Okay, so with the law >in place all these second thoughts and strange projections can just >evaporate. Actually, this is a nontrivial reason in favor of such laws. A law can help change a collective behavior pattern in which all the individual agents act rationally, yet the total result is far from optimal. For example: everyone slows down to stare at an accident on the freeway, and the result is a traffic jam in which every driver spends ten extra minutes driving just to see an accident that each driver individually would only want to spend ten extra *seconds* to see. Such patterns are common in interactions among people (they are often called Prisoner's Dilemma or Free Rider situations), and in general, individual rationality does not lead to a collectively optimal situation. The free market is a special case: the market "works" (in the sense it may be said to work) because each agent enters the marketplace *voluntarily*. But this is not the general case with social interactions. In the case of a passenger (or driver, for that matter) who feels it is "wimpy" or discourteous to use a seat belt in the absence of a law, a law may change the situation as Mitch describes above, so that for him using a belt is now the rational choice. The result is that at virtually no cost (since he is not being perceived as rude or a wimp, and it takes ?1.5 sec to buckle up), he gets in return an large increase in safety (50% reduction in chances of death or injury). Multiply this by all drivers and passengers so affected, and the net benefit to society would be large. Furthermore, the same result could obtain if a person is largely motivated by *habit* (which I suspect is often the case WRT seat-belt usage) rather than social norms that forbid wimpiness or discourtesy: a law could provide the situation that would change a person's habitual behavior at little cost but great benefit to the individual. But I'm speculating now. An excellent book on this topic is Thomas Schelling's *Micromotives and Macrobehavior*. Richard Carnes, ihnp4!gargoyle!carnes