Jason Palmer wrote: >The central concept in Bayesian analysis is _risk_.<
I don't know if I agree with this. If asked, I would say that a more central concept in Bayesian analysis is conditional probability. As I see it, the concept of "risk" involves an application, or "interpretation," of the standard probability calculus. Mathematically and logically speaking, notions such as the definition of conditional probability and the notion that the probabilities of exhaustive disjoint hypotheses sum to one (1) seem more fundamental to the thing that we call "Bayesianism." (Put it this way: Bayesianism has uses even when risk does not enter the picture or play a role in a problem involving uncertainty.) Jason Palmer: >.. the Judge can't make exceptions for individual cases. There should be only one consitent interpretation of the ordinance that applies to everyone.< This list shouldn't become a vehicle for discussion of legal fine points -- but in point of fact courts routinely carve out exceptions to "general" legal prohibitions and courts might very well do so with an ordinance of the sort I have posited. Jason Palmer also wrote: >So the Judge has two problems: decide what interpretation to give the law, and decide whether the defendant violated the ordinance according to that interpretation. Assume that the main problem is the former, and that the decision will be relatively straightforward once the interpretation is made. The Judge might then enumerate the possible interpretations,..< Tillers speaking: This is much, much easier said than done. Depending on how finely one wishes to slice the cake, there are probably hundreds of possible interpretive methods and it would be quite difficult and time-consuming for the judge to enumerate all the possibilities. But this does not mean that the judge would not or should not ignore many possible methods of interpretation -- because they seem to him or her as too improbable or absurd to worry about. But, but ... a quick glance of U.S. Supreme Court opinions suggests that even a small group of nine people are capable of favoring a wide variety of interpretive methods. But ... still this last caveat may be beside the point: a decision maker will routinely disregard highly improbable possibilities, possibilities that seem highly improbable. Jason Palmer wrote: >(2) The Council - an item comes before the city council concerning a possible amendment to the "no motor vehicles in the park on Sunday" ordinance, given the many complaints the council has been receiving from persecuted roller skaters. Assume that the council reasons as a whole (through discussion)..< Tillers: But this is not the way things actually work. Legislators can and do entertain quite distinct arguments for and against a proposed law. The effort to find an "authoritative" collective expression of legislative purpose is, many respectable people think, ordinarily quixotic. And if there is an agreed-upon authoritative expression of collective purpose (in, e.g., a committee report), the words used to express collective intent or purpose are invariably themselves ambiguous or uncertain to some degree, often to a very substantial degree. Jason Palmer: >The council must determine the risk involved in allowing or disallowing roller skating in the park on Sunday.< Tillers: Here you are talking about the ideal legislative process. That's another big can of worms. I was talking about the difficulty of divining what a legislative body intended by some (possible) decision taken in the past. The latter question remains a problem even if the possibility of formal amendment is open. *** Let me break off my comments about legal points here by emphasizing that interpretation of the "intent" or "meaning" of (apparent or possible) institutional decisions is a very complex business. If one wishes to persuade lawmakers and professional interpreters of such laws to embrace "alien" standards for decision making or the interpretation of the actions of lawmakers, it is very important to get a sense of how lawmakers and the professional interpreters of lawmakers' laws perceive their own activities and how they understand their tasks and problems. There is much disorder and uncertainty in the enterprise of the legal interpretation of putatively-authoritative legal pronouncements. Even the fundamental nature of lawmaking institutions is up for grabs. For example, some people think that all talk about the "intent" or "purpose" of a group of people is gibberish, whereas other people -- including many but not all judges -- think it makes eminent sense to talk about matters such as the "intent of Congress." The sorts of problems of interpretation that I have hinted at cannot be avoided. This is because instances always arise in which the words of a statute, ordinance, or other legal rule, norm, or principle do not have a plain and clear and definite meaning in the eyes of all people whose opinions count or even in the eyes of a single person such as a judge. (No effort to write absolutely crisp legal rules has ever succeeded -- or will ever succeed.) The process of "divining" the "true" meaning of legal words with uncertain meanings -- this is a process (as Vern Walker reminded us) that in some or many instances might better be characterized as the imputation of meaning(s) to fuzzy, rough words, or ambiguous normative statements --, this sort of process -- unless it is seen as _pure_ fiat, which some respectable people think is what ordinarily goes on in the process of the interpretation and application of pre-existing legal rules --, ---, the process of trying to divine the meaning of legal words forces judges to look for some sort of "evidence" of meaning. But the question of which matters count (or should count) as such evidence of meaning and the question of how much_ persuasive force any matter that admittedly does count are questions that are often themselves mired in controversy. All in all, the business of legal interpretation is not a pretty or clean picture. It would take a Herculean effort to capture all of the uncertainties involved in legal interpretation by using a formal apparatus such as Bayesian logic. (The same holds true if one uses a different kind of formalized logic -- and the same holds true if one uses NO formal grammar!) The longer I teach and write -- and I have been at this business of teaching law for quite some time -- the more I am inclined to think that conventional understandings of words and phrases (sometimes by the legal profession, sometimes by other groups) count for "quite a lot," more than most junior legal academicians recognize. But this sense of mine about the importance of conventional usage does not provide a true escape valve -- because even if conventional usage counts for a lot, it is not always decisive; and one must have a sense of when conventional usage counts for a lot and when it doesn't. The basic difficulty is that there are no really clean and persuasive and agreed-upon theories about the process of legal interpretation -- even though hundreds of U.S. law teachers publish hundreds of articles each year about the topic and even though many judges occasionally take the time to write down their "authoritative" thoughts about legal interpretation. (But note: mo solitary judge -- not even a Supreme Court Justice -- has much "authority" about questions of this sort). Thank you for your thoughts, Jason Palmer. Forgive me, everyone, if I have rambled on at too much length. My very best wishes for a happy new year, Peter T
