Legal norms are formed by rules and principles. Principles, just like rules, establish deontic propositions. But principles, in the legal domain, have only had close attention in recent years. Rules establish conditional program, with an antecedent which describes an action (condition), and consequence which prescribes legal consequence (conclusion). Principles have similar logical structure, but their program is intended for purpose. Thus, principles directly establish purposes which the rules intend to achieve (Eric, 2000, 185).
Rules and principles The discussion of principles is old. However, it was Esser (1964) who defined and inserted principle concepts in the context of legal discourse. In Law Theory, Dworkin (1978) had fundamental importance in distinguishing principles from rules. He claims that differences are mainly caused by the fact that unlike principles, rules have absolute obligations equivalent to 'all-or-nothing'. Principles do not have this kind of absolute obligation, and they could be used in ? future case, even when they are overridden.
To Dworkin, the selection or hierarchy of principles is established in dimension of weight, or in the importance of value. But Dworkin does not accept that rule prevails over another rule, by dimension of weight, just like principles do. Alexy (1978) agrees with Dworkin's ideas of principles, but he offers his own approach, in certain relevant points. mode of distinguishing rules from principles is the abstraction degree on their prescriptions. However, Alexy claims that the distinction is not only matter of degree, but also matter of quality.
Thus, conflict of rules is solved in validity domain, while collision of principles is solved on dimension of value (Bean, 2004, 85-178). It is clear that legislator can not foresee the entire future, to classify all possible situations which may occur in real life. And even when ? definition is given, it does not mean that description of the actual actions is complete. Hart's (1958) distinction between 'core cases' ('clear cases') and 'penumbra cases' ('hard cases'), is well-known which is based on the availability of legal knowledge.
In clear cases, it is possible to decide if the current case is an instance of the legal concept, based on the information of statute or judicial precedents. In hard cases, the judicial decision does not have additional knowledge to classify fact situation. So, in hard cases, whether certain case is Rules and Principles in Legal Reasoning 69 instance of legal concept this is uncertain. This occurs on account of the open texture of the legal norm. It could be observed that open texture is not ? particular characteristic of principles.
Gardner & Anderson cites as an example park regulation, forbidding the use of vehicles in the park. Although rule problem in classifying 'vehicles' exists, because its definition is not complete. It could be skateboard, car or anything else. So, rules also could have an open texture. What could be attributed as relevant criterion of distinction is the vague degree of the action described in the antecedent of the rule or principle. In rules, the antecedent establishes description of an action, although not in complete definition (Gardner & Anderson, 2004, 9-12).
The action explained could be open texture. But although an abstraction degree exists, an action is described in the antecedent. So the antecedent is determined, though uncertain and sometimes opens texture. In this case, the antecedent should be interpreted, namely rule that allows divorce, when marriage becomes insupportable. In principles there is not an action described in the antecedent. And this, because in principles, the actions are the conditions for the achievement of goal, as will be discussed.
Thus, any sufficient action to realise the purpose of principle could be classified as antecedent of that principle. The antecedent of principle is completely open-textured, or uncertain, and should be constructed.
The abstraction degree of principle when compared with rule increases considerably. An important note by Prakken (1997), is what he calls (and Gordon, 1991) 'under determination' and 'over determination' of open texture legal rules. According to Prakken, 'under determination' is kind of open texture, concerning problem of content: problem of whether certain fact situation can be classified as an instance of legal concept on the basis of established legal knowledge.
However, if conflicting classification rules exist, the open texture is 'over determination': ... there is related problem of open texture which indeed causes problems for logic. It is likely that when legal doctrine develops on the issue, after period of time body of conflicting information exists, consisting of judiciary decisions in the worst cases, expert opinions, dictionary interpretations, etc.