Indeed, the conclusion (the employer’s obligation to compensate the damages) necessarily follows from the premises (the norm  and the statement  which describes the employee’s damage): this is so-called deontic modus ponens. Observe that, in the passage under scrutiny, so-called “logical enrichment” is also applied.24 If there is a damage caused by the employee, there must be a compensation granted by the employer, both in the case that the damage is caused by the employee in carrying out her “ordinary” tasks (let’s symbolize them by “I”) and in the case it is caused by the employee in carrying out “extraordinary” tasks he has voluntarily undertaken (symbolized by “L”).
The identification of new relevant properties does not alter the nature of reasoning, provided that the normative basis is enlarged in order to contain further norms from which one can derive such properties: i.e. provided that implicit exceptions are made explicit. If relevance of properties is only recognized implicitly, then what we have is a case of enthymematic reasoning.
A relevant property, ruling out enrichment (or, from a slightly different perspective, calling for the revision of the premises) in the case at hand, is found in the following lines25:
An employee may carry out, at times, without the employer knowing, a task that was up to another employee. If damages arise therefrom, in order to determine whether this is within the risk of the enterprise, one should consider the greater or lesser affinity between the duties of the employee and the specific activities carried out by him, and the extent to which the performance of the enterprise activities may be divided into branches, offices, and factories.
According to Trimarchi (who “introduces” this norm into the Italian legal system, inspired by the U.S. Restatement of the Law of Agency),26 when an employee undertakes an activity which is up to another employee, without having the skills, exceeding his competences, and without the employer knowing (let’s symbolize by “M” this set of circumstances), the employer does not respond for damages. In symbols:
In the passages we have quoted, Trimarchi enlarges the normative basis of vicarious liability of the employer, first reconstructing norm  regarding the liability for the employee’s conduct, and then identifying the properties which rules out the application of such a norm, or more precisely rules out “logical enrichment” regarding  in a certain context – as it happens in . However, it is manifest that if one wants to avoid inconsistencies within the system, the normative basis must be reconfigured as follows:
Indeed, deductively developed, such a normative basis constitutes a complete and consistent normative system.27
10.3.2 Other Kinds of Derived Norms
From the point of view of the “empirical” analysis of juristic reasoning, it can be observed that jurists carry out many kinds of reasoning which are not deductive in nature.
According to a widespread opinion among jurists, deductive reasoning is insufficient to reconstruct the conceptual content of a legal system. This is due, among other things, to the important fact that the law itself admits, in addition to deductive reasoning, also other types of reasoning.28 As is known, it may be the case that a legal order admits (and in certain cases even requires) that legal officials, jurists and lawyers reason in a non-deductive way (e.g. analogically).
In addition to this, there is a widespread view among jurists, according to which legal scholars cannot confine themselves to deductively developing a set of norms (unless they want to build a merely “tautological” science) but should instead “systematize” legal materials, which, at first, often appear under the forms of an unordered set of normative provisions.29 Therefore, it is common for jurists to derive norms from legal materials by means of logically unsound reasoning.
From the point of view of rational reconstruction, it is possible to distinguish the procedures used by jurists to develop legal requirements, at least between: (1) arguments expressly based on specific provisions of law; (2) arguments that have no explicit recognition in the law, but which are implicitly required by the law; and (3) arguments, not expressly provided or implicitly required by law, but developed by legal scholarship.
Some qualifications are in order here.
The first category contains those arguments, specifically productive or integrative of the law (such as analogy in the Italian legal order, or the variety of integrative arguments allowed by the first section of the Swiss Civil Code30), which have their foundations in legal provisions.
Although these arguments are generally deemed to be invalid from a logical point of view, there is no doubt that they are more than “sound” from a legal point of view, since they are allowed, if not imposed (at least in some cases), by law itself.
The second category includes those kinds of reasoning that, though not being expressly recognized by the law, are implicitly required by the law in order to regard it as a complete and consistent whole. In particular, the judges, who are the addressees of a general prohibition of denial of justice and of the obligation of justifying their decisions on the basis of pre-existing legal norms, cannot but conceive the law as a complete and consistent normative set,31 otherwise they could not judge or could not base their decisions on legally valid norms. Well, all the (logically unsound) procedures which, from time to time, the judges (and jurists) use to reach a solution for an unqualified case or a inconsistently qualified case, are admitted in so far as law requires the court to resolve any dispute whatsoever. In other words, there are situations where the only existing option for the judge of deciding a case on a legal basis consists in using arguments, not explicitly provided by the law, which allow one to fill in a normative gap or to solve an antinomy. These arguments usually make use of positive norms to create other norms. A paradigmatic example of such kind of arguments is the a contrario argument in its productive function (Expressio unius est exclusio alterius).
Finally, there are procedures that are used to produce unexpressed norms, which are neither provided for, nor implicitly required by the law, but are grounded on extra-legal elements, and especially on the ideological theses defended (often surreptitiously) by legal scholars. For instance, jurists interpret constitutional provisions in a “dissociative” way, in order to distinguish cases that were not differentiated by the lawgiver.32
We have just seen that jurists often use different rules of inference to reach, on several occasions, diverging results. It is even more common, though, that they change the premises of their reasoning (rather than the rules of inference), by adding to positive norms non-positive premises derived by legal scholarship.
As a consequence, the development of the normative basis can be carried out, not only by changing the rules of inference (as we have explained so far), but also (and even more frequently) by adding “non-positive” premises of different kinds. Unluckily, this feature of the logical development of a normative basis has seldom been taken into account in relevant literature.33
In addition to specific dogmatic theses elaborated by jurists, the discourse of legal scholarship is full of conceptual theories, which are not only used to “integrate” the discourse of normative authorities, but are likely to affect the interpretation of the relevant statutory provisions and the normative consequences which can be derived from them.
Examples are legion. It suffices here to record just one of them, concerning the “legal nature” of pre-contractual responsibility in the Italian legal system, where section 1337 of the Italian Civil Code34 has been interpreted, alternatively, as bearing upon an offense tort or as a responsibility of a contractual nature. The former thesis has been propounded on the basis of the theory according to which interest protected in terms of pre-contractual liability is that of freedom of contract. The latter thesis has been defended by arguing mainly that “the responsibility is of a contractual kind, on the assumption that torts would require violation of absolute rights, while those at play in negotiations are of a relative nature”.35
Another major operation carried out by legal scholarship is so-called “legal induction”, which consists roughly in deriving principles from specific rules. In other words, it consists in “summing up” a large number of rules, which have aspects in common, by means of one or more general principles. The logical nature of this process is controversial. Some authors hold that it has a deductive nature, whereas others believe it is a genuine inductive process.
For Alchourrón and Bulygin (1971, pp. 78–84), for instance, in reformulating several norms (which have at least one common element) into a more general norms containing such a common element and normatively equivalent to the original norms, the inferential nature of the procedure is ensured by the fact that the number of norms is finite (and that the conclusion necessarily follows from the premises). From the norms N1 (Dx & Ix → OR); N2: (Dx & Lx → OR); N3: (Dx & Sx → OR) one can surely infer the norm (Dx → OR). It is a strictly deductive inference, since the transition from more detailed norms to the more general rule is a strict inference, and not merely a “probable” one.
It should, however, be noted that, in addition to N1, N2, N3, one can derive from N4, by means of enrichment, many other norms, which were not previously belonging to the legal order. This evidently shows that the argument according to which legal induction is not a creative process can be maintained in so far as the context (i.e. the normative system in which the induction is carried out) does not change.
A view which runs counter to that of Alchourrón and Bulygin is defended by Jori, who holds that “any group of norms that have something in common can be used to ‘induce’ an infinite number of principles, that justify them (for example, by varying the level of generality at which ‘induction’ is stopped): from each of these different principles, then, it will also be possible to deduce the correct set of original norms”.36
At any rate, one can find in legal scholarship examples of both deductive generalization (à la Alchourrón e Bulygin) as well as examples of strictly inductive generalization (à la Jori).
An example of the first kind of generalization is derivation of the so-called “principle of safety and health of the workers in working places”, which is drawn from several provisions of the Italian legal system, such as sections 2, 32, 35, 41 of the Constitution, and section 2084 of the Italian Civil Code, as well as from many provisions of the legislative decree N. 626/1994. Generalization seems to be deductive in the case at hand, since given those premises (i.e. that specific meaning-attribution to that sentential basis) one cannot but derive such a principle (and there are no other norms of labor law which put such a principle into doubt).37
By contrast, an example of a principle extracted by means of a genuine inductive generalization is given by the principle of strict liability for enterprise risk.38 Such a principle may be inferred, although not in an uncontroversial way, from some of the norms regarding torts. However, there are many other norms which justify the opposite principle, according to which the employer only responds in case of negligence. It is clear that also in this case the induction of the principle of strict liability is a “finite” one. But such finiteness is always capable of being jeopardized by adding new norms to the normative basis. As a consequence, its results are merely, as it were, “probabilistic”.
10.4 Reformulation and Choices Among Alternative Normative Systems
Legal principles – often the product of the “inductive” activities we have just analyzed – play a twofold “systematic” role: (1) on the one hand, they constitute the ultimate “axiomatic basis” of a certain system of norms; (2) on the other hand, they justify the norms of the system, in that they are the axiological foundations of such norms. From combining such two functions, one can infer the distinction between “justifying” axiomatic bases and “non-justifying” axiomatic bases and observe that, generally, jurists prefer the former over the latter.
According to this view, principles are the elements which are capable of making a certain normative set consistent, complete, and axiologically coherent.39 This would be for the following reasons. First, a principle is often (if not always) “in collision” with (at least) another principle, so that by introducing a preferential ordering among principles one can order the whole normative set (in other words, by making consistent the set of the axioms one makes consistent the theorems too). Secondly, a principle allows one to infer other norms in addition to those from which it was derived (i.e. the completeness of the axioms warrants the completeness of the theorems). Finally, it is a widespread view that principles allow one to reduce a certain normative set to its ultimate values, highlighting its possible axiological defects and disharmonies. In the example above, the principle of strict liability, inferable from some of the norms on torts, was in conflict with other norms of the same field, from which it was possible to induce the principle of negligence or fault liability: in lieu of a unique system of liability for enterprise risk, legal scholarship has produced two, each of which may be traced back to a different principle.
The reformulation of the system makes it possible to single out the “founding” elements of a normative system, highlighting the formal and axiological characteristics, and suggesting, if necessary, the expulsion, from the normative set, of the norms that do not allow this set to have a genuinely systematic nature.
In particular, such a reformulation makes it possible to reconstruct a normative system as a deductive set, from which all the consequences can be derived by deduction. In other words, if it is true that before the reformulation, a normative set may have gaps and contradictions, as well as axiological disharmonies, it is also true that, after that the reformulation took place, it is easier to connect the normative set to the systematic characters of which the law is predicated.
This can be demonstrated, by formalizing the Italian regulations on strict liability for enterprise risk which were mentioned previously.
In “axiomatic” terms, the system of torts in Italian legal scholarship is formed by the two following principles, each of which is (supposedly) derivable from some provisions of the civil code:
Which means “For any x, if x is a damage, then it is obligatory to redress it”; and
This means “For any x, if x is a faultless damage, then it is not obligatory to redress it”. This is tantamount to the usual slogan in Italian legal scholarship “No liability without fault”.
Clearly, this set of norms is inconsistent, to the extent that  connects “Dx & ~Fx” to the contrary solution to the one connected by  to the same case.40 If one rephrases  in the sense that it includes negligence or fault in its formulation, one can clearly grasp that, for the principle at hand, it is irrelevant whether there is fault or not:
In this sense,  is a happy formulation of the principle of strict liability, since one can derive from it – as well as  – both the norm “Dx & Fx → ORx” and the norm “Dx & ~Fx → ORx”.
There is no way of making the system of torts consistent, if not by “repealing” one of these two general norms. In order to make such a system consistent, one must reject those norms from which the principle of fault liability can be derived or reinterpret the provisions from which such norms are derived. By contrast, if one wants to make consistent the system of fault liability, then one has to reject those norms from which the principle of strict liability is derived: what can be done also by reinterpreting the provisions from which it is extracted.
The reformulation of the system makes it possible to understand more clearly the choice between two alternative sets which have as their basic principles the standards we have just mentioned.
10.5 The Formal Features of the Normative Basis
In the formal analysis of the formal defects of normative systems, commonly an abstraction is made regarding interpretive questions. If one removes such an abstraction, one can notice that the formal properties of a system depend, to a great extent, on the ascription of meaning to the provisions which constitute the sentential basis identified by the jurist.
In an interesting case discussed before the European Court of Justice (ECJ),41 the relationship of priority between two Directives was debated. The first one was the Doorstep Selling Directive, the second one was the Consumer Credit Directive. Both directives provided two incompatible solutions for the same generic case, i.e. the right to cancel a consumer’s loan secured by charge. While the Consumer Credit Directive did not allow for such a cancellation (providing, at section 2.1(a), the exclusion of the applicability of the Directive to such a case),42 the Doorstep Selling Directive recognized it, within certain limits, at section 5.1. Finding itself in front of such an antinomy, the Court (re)interpreted section 2.1 of the Consumer Credit Directive as not applicable to the case at hand.43
Interpretation is, inter alia, the operation by means of which the jurist (or the judge) builds up a normative basis, starting from a sentential basis. Once having selected, more or less discretionally, the provisions composing the sentential basis, the jurist deals with the possible semantic options which it admits in order to build up a normative basis.
Indeed, in this passage from the sentential basis to the normative basis, the jurist makes choices that will have repercussions on the formal properties of the normative set. She can interpret provisions, in fact, so that gaps or antinomies are produced or ruled out.44
It is important to recall here the distinction, previously introduced, between first and second interpretation. First interpretation is the operation by means of which jurists, dealing with some of the sentences of the legal sources, attach a first, tentative, meaning – which usually consists in what is called “current legal meaning”, i.e. the meaning which is widespread within the legal community, on the basis of settled doctrinal and judicial theses.
In approaching a certain set of legal materials, the jurists use some doctrinal or judicial theses, which lead them to spot some formal features which we can call prima facie, in analogy to the interpretation which produces them. Such formal features are then re-elaborated during the process of reinterpretation, so that it is possible to maintain that a first “systematization” is carried out at the interpretive level.
Such systematization responds to the regulative ideal that law, as a product of doctrinal interpretation, must have a systematic nature. However, if law must have a systematic nature, and if jurists may carry out several operations on pre-interpreted materials, then a more detailed analysis of such operations is needed in order to reconstruct the methods by means of which such a nature is attributed or denied. In the next section, we shall deal with the operations which are used to deny or assert that law is incomplete, while in the following sections we shall examine those operations which are designed to affirm or deny that law is inconsistent.
10.6 The Identification of Gaps
The traditional account of normative gaps understand them as “data of experience”, which jurists cannot but ascertain.45
This is not the case: on the one hand, expressed norms are the product of a complex interpretive process, which in any of its phases involves interpretive choices and is influenced, at every step, by dogmatic theses. On the other hand, unexpressed norms are derived from expressed norms by means of a variety of inferential ways, the choice among which is also influenced by doctrinal theses regarding interpretation and logical development.
Hence, if norms are the product of such a complex interpretive and “expansive” process, and gaps are regarded as the lack of a norm, the presence or the absence of a gap in a certain normative system depends upon a series of lato sensu interpretive, constructive, and systematizing operations carried out by jurists.
In facing the problem of gaps, then, it is important to call to mind some basic concepts, such as those of:
“Normative provision”, by which we understand any sentence of the legal sources;
“Expressed norm”, by which we understand the meaning-content of a certain normative provision, assigned to it by an act of interpretation (i.e. meaning-ascription)
“Unexpressed norm”, by which we understand a norm derived, by means of several kinds of inferences, from an expressed norm.
Moreover, it will be useful to remind the distinction between first (or prima facie) interpretation and second interpretation (or reinterpretation), understanding the former as an attribution of a tentative meaning, product of a first “intuitive” approach to the sources to be interpreted, and the latter as the final meaning, product of a “all-things-considered” investigation on the elements which are relevant for attaching a certain set of meanings to a certain sentential basis.
The distinction between first and second interpretation makes it possible to refine the conceptual analysis of the operations carried out by jurists in order to “ascertain” the incompleteness of a certain system of norms.
As we have noticed, interpretation may rule out or create gaps, but it cannot fill them up: the filling-up of gaps is something which occurs when interpretation has already been carried out.46
But it is also true that, in jurists’ works, the cases in which a gap is expressly admitted are relatively rare. The construction of normative materials usually is carried out in a way that it gives the impression that the law is always complete, at least in the sense that it contains no implicit gap.47 In other words, the jurist, when recognizing an explicit gap regarding a certain system, tends not to admit that the law does not provide any solution at all for a certain generic case. There is always the possibility, for instance, that a principle can be developed in a way that it allows one to find a solution for such a case, or that the analogical application of a norm, prima facie not taken into consideration, can provide the normative problem with a solution regarded as satisfactory or reasonable by the jurist.
Let us consider the following example. In order to avoid responsibility, some enterprises assign some risky activities to other enterprises (so-called “satellite enterprises”), which are often constituted with small capitals, and hence are barely capable of bearing the economic burden of repairing damages. On a first interpretation, Italian law provides nothing on the joint responsibility of both enterprises. Only the enterprise which materially carries out the activity (i.e. “the satellite enterprise”) ought to restore the damaged subjects. Obviously, this involves some great difficulties regarding the safeguard of damaged people and the distribution of the risk in carrying out the dangerous activity: there is indeed a high probability that the damaged subject will be unable to receive compensation. In order to avoid such an undesired effect and fill up the gap regarding the responsibility of the contractors, Italian jurists have analogically extended, to the case at hand, section 2049 of the Italian Civil Code (which provides that “The owners and the clients are responsible for damages caused by the unlawful acts of their workers and clerks in the performance of duties to which they are put”), and so regarded the contractor enterprise liable for damages (of course, jointly with the contracting “satellite enterprise”).48
The identification of a gap is only the last, possible, stage of a composite reconstructive process. More precisely, one can distinguish at least six operations carried out by jurists in order to prevent or create gaps, and that allow the jurist, respectively, to avoid or carry out the integration of a certain normative micro-system49: (1) prima facie negative ascertainment, (2) prima facie positive ascertainment, (3) creation, (4) prevention, (5) pondered weak ascertainment, and (6) pondered strong ascertainment.