The relationship between international and national law is a topic of great importance. Generally, the floor has been divided between dualism (Section 1.1), as developed by Heinrich Triepel, and monism (Section 1.2), mainly formulated by Hans Kelsen, both of which need to be reviewed critically from today’s perspective. I argue that these theories can no longer comprehensively explain the relationship between international and EU law or EU and national law and that due to their emergence almost a century ago, they must be understood in their historical context. Current challenges posed by international or supranational organizations such as the EU, and the development of international law in general, overburden these outdated theories.
1.1 Dualism: Liberation from International Law as “External State Law” 125 Years Ago
The international and national legal orders are “two circles, which possibly touch, but never cross each other.”Footnote 4 This is the famous statement made by the then only thirty-year-old Heinrich Triepel in 1899, which forms the cornerstone of the dualistic divide of international (or EU) and national law. Dualism’s divide of legal orders was primarily based on the view that the law of the international (or EU) and national legal orders emanate from different sources, leading to the supposition that international (or EU) law and national law arise from different legal orders relying on different grounds for validity.Footnote 5 Although it still holds true that international, EU and national law emanate from different sources, dualism also assumes that the addressees and content of international and national law cannot be identical.Footnote 6 Thus, dualism turns a blind eye to direct interaction between international law and individuals. It does so by stating that international law is purely inter-State law and can only stipulate obligations for States;Footnote 7 nor does international law share the same addressees with EU or national law.Footnote 8 The division of the legal systems implies that international law may not derogate from national law, and national law may not derogate from international law.Footnote 9 In order to give international law an effect within a national legal system, dualism demands a special procedure to transform or incorporate the international norm into a national norm.Footnote 10 As a result, the basis of validity of international law within national law rests solely within national law, and the basis of validity of EU law within national law rests, too, solely within national law.
Dualism faces serious difficulties explaining the basis of international or supranational organizations, because, according to dualism, there would be one international and as many x-national bases of validity of international or supranational organizations as there are Member States.Footnote 11 In other words, the validity of an international organization would have to be divided up over its Member States instead of having a uniform validity. Equally hard to grasp is the concurrent (dualistic) assumption that international, EU and national law by default cannot have the same content or addressees.Footnote 12 This assumption is flawed as it would make norm conflicts between international, EU and national legal orders impossible, which is not the case. Norms from overlapping legal orders conflict constantly. If, for instance, EU law never conflicted with national law, the primacy of EU law would be meaningless.
While these flaws are obvious for us today, it was not so when dualism was emerging at the turn of the twentieth century. One flaw that is evident today is the dualistic assumption that international law (EU law did not even exist at that time) is purely inter-State law and so can only oblige States but not individuals.Footnote 13 While this was certainly true when Heinrich Triepel was shaping dualistic thinking, it can no longer be perceived as an accurate depiction of international law today. International law nowadays also addresses individuals directly and shapes national law in many ways. Moreover, trying to fit EU law and its relationship with international and national law into a dualistic scheme is like attempting to square the circle, as the dualistic assumptions do not match our understanding of EU law, which has at its core primacy and direct effect. EU law is binding on national authorities and the basis of validity of EU law is not dependent on national law. Moreover, if there is a conflict between EU and national law, EU law takes precedence over national law.
Historically, dualism was progress, as the separation of international and national law helped international law become independent. Thus, dualism liberated international law from being understood as “external State law,”Footnote 14 and was even referred to as a “cleansing thunderstorm” by the monist Alfred Verdross.Footnote 15 In sum, the legal landscape has changed drastically since the turn of the twentieth century, and the core assumptions of dualism are no longer correct. As a consequence, dualism fails to explain the relationship between international, EU and national law today.
1.2 Kelsenian Monism: A Quest for Purity at the Expense of Plausibility
The main characteristic of monism is the assumption of a single unified legal system. Monism was developed most prominently by Georges Scelle, Hans Kelsen and Alfred Verdross at the beginning of the twentieth century.Footnote 16 It is Kelsenian monism – and to some extent this also includes Verdross’ conception – that still enjoys substantial popularity and is arguably the most sophisticated account of monist theories. Therefore, I will focus on Kelsenian monism, which must face the criticism of having a highly fictitious understanding of the world: nothing less than the “unity of the legal world order” is proclaimed.Footnote 17
According to Kelsen, a legal order is a multiplicity of general and individual norms that regulate human behavior.Footnote 18 This multiplicity constitutes an order if it forms a unity. Unity in turn is established if these norms have the same basis for validity.Footnote 19 This understanding is based on the famous Kelsenian chain of validity, because the unity of a legal order is formed by the chain of validity.Footnote 20 Therefore, this understanding of a legal order is necessarily connected with the Kelsenian pure theory of law because law has to be perceived from one perspective as an noncontradicting single entity.Footnote 21 It is this understanding that undergirds Kelsenian legal monism, stating that if international, EU and national law are valid legal orders, they have to form a unity.Footnote 22 Different legal orders can only be considered valid if they have the same basis for validity.Footnote 23 The relationship between these legal orders must then be conceived of in either hierarchical or horizontal terms with separated spheres of validity. The latter conception, however, necessitates a higher order that entails a norm being the basis of validity for both legal orders.Footnote 24
This understanding results from Kelsenian adherence to neo-Kantian epistemology, “because it is only this method [the monist concept of law] and its focus on the manner of cognizance, not its objects, which allows to ascertain a priori how positive law is even possible qua object of cognizance and qua object of the legal science.”Footnote 25 In Kelsen’s own words, “[t]he unity of national law and international law is an epistemological postulate.”Footnote 26 In a more extensive manner he stated:
It is … true, in the sense of Kant’s theory of knowledge, that legal science qua cognition of the law is like all cognition: It is constitutive in character and therefore “creates” its object in so far as it comprehends its object as a meaningful whole. Just as natural science, by means of its ordering cognition, turns the chaos of sensory impressions into a cosmos, that is, into nature as a unified system, so likewise legal science, by means of cognition, turns the multitude of general and individual legal norms issued by legal organs – the material given to legal science – into a unified system free of contradiction, that is, into a legal system.Footnote 27
Moreover, according to him, “[i]t is logically not possible to assume that simultaneously valid norms belong to different, mutually independent systems.”Footnote 28 Hence, Kelsenian monism is also unthinkable without the Kelsenian quest for purity fueling his pure theory of law. What is appealing about Kelsenian monism is the attempt to understand both international and national law as law with the same conception of law, which allows for a comparison, and a succinct solution to legal norm conflicts. However, it is the quest for purity in the Kelsenian enterprise and the claimed epistemological basis that is understandable considering the historical circumstances under which Kelsen developed his legal theory. Yet it is precisely these elements that expose Kelsenian monism to strong criticism today.
Dualism and monism alike have been heavily criticized. For instance, Armin von Bogdandy holds that “from a scholarly perspective, they are intellectual zombies of another time and should be laid to rest, or ‘deconstructed.’”Footnote 29 Yet monism in particular proves to be a hard-to-kill zombie. Recently, Paul Gragl has advanced a sophisticated account defending Kelsenian – or, as he puts it, legal monism as imagined by the Vienna School of Jurisprudence and the pure theory of law.Footnote 30 He defends Viennese legal monism with its “epistemological terms of the pure theory of law,”Footnote 31 upholds its “descriptive value”Footnote 32 and finally even claims its “moral superiority” over other theories on the relationship between legal orders.Footnote 33 This deserves further scrutiny, with the goal to deconstruct Kelsenian monism as suggested by Armin von Bogdandy.Footnote 34 We will begin by looking at the claim that legal monism as envisaged by the Vienna School of Jurisprudence follows from an epistemological and logical necessity.
1.2.1 Kantian Epistemology as the Basis for the Pure Theory of Law and Kelsenian Legal Monism
Gragl correctly points to the Kelsenian claim that his pure theory of law and thus his version of legal monism follow from Kantian or neo-Kantian epistemology.Footnote 35 When Immanuel Kant asks “how subjective conditions of thinking should have objective validity,”Footnote 36 Kelsen asks “how to cognize whether a given legal norm is objectively valid or not.”Footnote 37 We will first revisit how Gragl portrays Kant, whose undoubtedly important and influential work dates back to the eighteenth century. Second, we will revisit some of the criticism that was advanced against Kant by other important philosophers in order to, third, examine briefly how the philosophical discipline of epistemology has evolved from the eighteenth century until now. Beyond that we will also look at neo-Kantian philosophy, as this philosophy is claimed to be the touchstone of the Kelsenian pure theory of law and legal monism (Section 1.2.2). This will allow us to evaluate whether this is a solid epistemological basis for making the leap to Kelsenian monism and a sound legal epistemology today (Section 1.2.3). In other words, after discussing the (neo-)Kantian epistemological basis, we will deal with the question of whether this is a convincing basis for the law, since the analogy between Kelsenian legal epistemology and Kantian epistemology depends on it. The Kantian enterprise asks “how subjective conditions of thinking should have objective validity” and thereby engages with the relation between (subjective) thinking and the (objective) world. The Kelsenian goal – in contrast – is to find out “how to cognize whether a given legal norm is objectively valid or not” and, thus, is about the validity of norms. Pointedly, the commonality and therefore the justification of such an analogy is the very same letters, “v a l i d,” apart from which both endeavors – questions of what is knowledge (of the external world) and questions of what is law or legal knowledge – are worlds apart. Therefore, we should carefully separate validity claims about scientific theories and validity claims pertaining to norms. Before addressing such a critique focused on the appropriateness of this analogy, however, we will begin with Kantian epistemology as portrayed by Gragl.
Kant famously criticized radical rationalism and radical empiricism. In his Critique of Pure Reason Kant famously holds that “[t]houghts without content are empty, intuitions without concepts are blind”Footnote 38 and points, in the words of Gragl, to the “opaque concept of the transcendental thinking self.”Footnote 39 This is because only from the union of thoughts and intuitions “can cognition arise.”Footnote 40 In brief, “whatever a person is thinking, there always is a subject of thought which can never be made an object.”Footnote 41 Therefore, “the self which thinks cannot be an object of experience”Footnote 42 and, “since the unity of the transcendental self is not experienced, its unification of ideas can be regarded as objectively valid.”Footnote 43 “Owing to its nature of being a necessary (and hence not being experienced as a contingent) self, the transcendental self can unite all thoughts in a non-contingent manner, and by doing so, it can represent necessary connections in nature.”Footnote 44 That is – according to Gragl – the basis for Kant’s “Copernican” revolution holding “that it is not our knowledge that must conform to objects, but that objects must conform to our knowledge.”Footnote 45
First, Gragl deserves praise for having outlined what, “eventually, influenced the pure theory of law, trying to find a way between metaphysical natural law and empiricist sociology or psychology.”Footnote 46 All too often, we read about dualism and monism without a neat sketch of the theoretical preconditions of these theories. However, having described the preconditions clearly, further questions are provoked. A first intuition might be that, despite the impressive leap accomplished by Kant back in time, the philosophical discipline of epistemology has not stood still since the eighteenth century. Although this in itself might not be a sufficient criticism,Footnote 47 such skepticism might make us wonder, in general, how to figure out what is state of the art in epistemology today and, in particular, which arguments have been advanced against the Kantian concept of “transcendental idealism.” Gragl is aware of Hilary Putnam's criticism of this position as solipsistic.Footnote 48 He negates that criticism of Kant, however, by holding that “it is impossible to make such judgments about the thinking self.”Footnote 49 Rather, Gragl states, the transcendental self “is a condition for, not an object of knowledge.”Footnote 50 Before we see how this applies to the law, we need to consult further criticism that has been advanced against this position.
To begin with, a caveat is in order. It is clearly impossible within the framework of this book to outline the theory of knowledge as it stands today. Nor is it possible to take a sophisticated look at Kant’s elaborated epistemology. What must suffice for the purpose of this book is to show that Kelsenian legal monism, with its heavy reliance on (neo-)Kantian epistemology, does not take into account the critique that has been advanced against Kant in this regard and the development of epistemology in general since 1781 and 1787.Footnote 51 This, as we will see, is a major mistake.
Yet, to provide sufficient context, we need to understand what drove Kant to write his Critique of Pure Reason. According to our intuition, and also for a long time in philosophy, a statement is considered to be true if it describes reality aptly.Footnote 52 Conceptions of truth that follow such an account were and still are usually referred to as “correspondence theories of truth” and can be traced back to ancient Greek philosophers. Aristotle, for instance, famously stated that “[t]o say of what is that it is not, or of what is not that it is, is false, while to say of what is that it is, and of what is not that it is not, is true.”Footnote 53 Thomas Aquinas similarly stated that “[t]ruth is the adequation of things and intellect” and thus “[a] judgment is said to be true when it conforms to the external reality.”Footnote 54 According to this approach, we can consult a “truthmaker” in order to find out whether a statement is true. A truthmaker is anything that makes a statement true.Footnote 55 René Descartes, another prominent advocate of the “correspondence theory of truth,” pointed out the obviousness of this approach, which is a considerable strength. In fact, Descartes is said to have brought about a Cartesian revolution in philosophy as he famously identified its foundations. According to Dummett, “the Cartesian revolution consisted in giving this role to the theory of knowledge.” Descartes asked, “What do we know, and what justifies our claim to this knowledge?”Footnote 56 Cartesian doubt was introduced by Descartes as a methodology to question our knowledge as a route to the point of certain knowledge. This led Descartes to question what makes you certain that you are awake and not dreaming. He answered this in retrospect by stating that “when I distinctly see where things come from and where and when they come to me, and when I can connect my perceptions of them with my whole life without a break then I can be certain that when I encounter these things I am not asleep but awake.”Footnote 57 Moreover, with his “cogito ergo sum” he concluded that at least his own existence was proven precisely by himself “thinking all [his] thoughts might be mistaken.”Footnote 58 In a sense concerning the correspondence theory of truth, Descartes was in good company with such important philosophers as Baruch de Spinoza, John Locke, Gottfried Wilhelm Leibniz, and David HumeFootnote 59 and Immanuel Kant,Footnote 60 in a way.Footnote 61 However, can we linguistically portray something external to linguistics? What does it actually mean that a statement matches reality? Is it not the case that this theory presupposes truth, for if it would not do so, how could we validate our truth claims?
To understand these objections and to relate the Kantian critique to early versions of such an approach we must first consider David Hume, who questioned whether we have direct access to the external world. According to Hume, we can only relate to the external world via our impressions.Footnote 62 Hume differentiated between impressions (feelings) and ideas (thinking) while he held that all ideas are “faint images”Footnote 63 – in other words, copies of impressions.Footnote 64 Impressions, however, face the problem of induction. According to Hume, we can only explain that we process impressions inductively, but we cannot justify that we do so. In his words, “’[t]is therefore by experience only, that we can infer the existence of one object from that of another.”Footnote 65 So, he goes on, if we remember that when we perceive a flame we have also felt heat, we likely conjugate all past instances of seeing a flame and feeling heat. Hence, “[w]ithout any farther ceremony, we call the one cause and the other effect, and infer the existence of the one from that of the other.”Footnote 66 However, this operation is only perceived and remembered by our senses as we make “constant conjunctions.”Footnote 67 He hypothesizes “that all our reasonings concerning causes and effects are deriv’d from nothing but custom; and that belief is more properly an act of the sensitive, than of the cogitative part of our natures.”Footnote 68 This view has been named radical empiricism, for it holds that, ultimately, we cannot access the external world. We are left with the impressions from our senses. In Hume’s beautiful prose:
Reason first appears in possession of the throne, prescribing laws, and imposing maxims, with an absolute sway and authority. Her enemy, therefore, is oblig’d to take shelter under her protection, and by making use of rational arguments to prove the fallaciousness and imbecility of reason, produces, in a manner, a patent under her hand and seal. This patent has at first an authority, proportion’d to the present and immediate authority of reason, from which it is deriv’d. But as it is suppos’d to be contradictory to reason, it gradually diminishes the force of that governing power, and its own at the same time; till at last they both vanish away into nothing, by a regular and just diminution.Footnote 69
It was this powerful finding by Hume that awoke Kant from his self-diagnosed “dogmatic slumber.”Footnote 70 While, according to Hume, there is no a priori possibility to discover what is out there without our senses and, thus, there is also no a priori causality as a relation between things, Kant famously criticized radical rationalism, but also radical empiricism. In his Critique of Pure Reason, Kant agrees with Hume to a large extent when he states that “[w]hat may be the case with objects in themselves and abstracted from all this receptivity of our sensibility remains entirely unknown to us.”Footnote 71
However, Kant, in contrast to Hume, does not think that causality is a relation between things, but an a priori necessary precondition of human beings perceiving things. And, more controversially, that things are also causally constituted. To this end, it is important to note the difference between a priori, which basically means independent of experience, and a posteriori, which means on the basis of experience.Footnote 72 Moreover, we can also differentiate between analytical judgments and synthetic judgments. Kant specifies this as follows:
In all judgments in which the relation of a subject to the predicate is thought (if I consider only affirmative judgments, since the application to negative ones is easy), this relation is possible in two different ways. Either the predicate B belongs to the subject A as something that is (covertly) contained in this concept A; or B lies entirely outside the concept A, though to be sure it stands in connection with it. In the first case I call the judgment analytic, in the second synthetic.Footnote 73
Analytical judgments, thus, are in a way given to the subject. Synthetic judgments are not contained in the subject but, nevertheless, are related to it.Footnote 74 As an example, Kant mentions that “[a]ll bodies are extended” is an analytic judgment, whereas “[a]ll bodies are heavy” is a synthetic judgment.Footnote 75 Having made these distinctions, we can principally illustrate the distinction between Hume and Kant. While for both, all analytical judgments are a priori, it is only Kant who considers the possibility of synthetic judgments being a priori.Footnote 76 Figuring out how such a priori synthetic judgments are possible is the task of a “transcendental critique.”Footnote 77 Causality, to return to the example, is considered by both Hume and Kant to be a synthetic judgment. However, the latter also considers causality an a priori judgment. Causality cannot be justified by custom as we could repeatedly ask for the beginning of the cause. Hence, only “because we subject the sequence of the appearances and thus all alteration to the law of causality that experience itself, i.e., empirical cognition of them, is possible.”Footnote 78 In other words, the law of causality is a precondition for the possibility of representation, and thus it is a transcendental argument, prior to experience.
Furthermore Kant distinguishes mere illusion, the appearance of objects and things in themselves:
If I say: in space and time intuition represents both outer objects as well as the self-intuition of the mind as each affects our senses, i.e., as it appears, that is not to say that these objects would be a mere illusion [“Schein”]. For in the appearance the objects[, and] indeed even properties that we attribute to them, are always regarded as something really given, only insofar as this property depends only on the kind of intuition of the subject in the relation of the given object to it then this object as appearance is to be distinguished from itself as object in itself. Thus I do not say that bodies merely seem to exist outside me or that my soul only seems to be given if I assert that the quality of space and time – in accordance with which, as [a] condition of their existence, I posit both of these – lies in my kind of intuition and not in these objects in themselves.Footnote 79
What is important here is to highlight that Kant – in a way as a response to the challenge of David Hume’s skepticism – was eager “to show that a critique of reason by reason itself, unaided and unrestrained by traditional authorities, establishes a secure and consistent basis for both Newtonian science and traditional morality and religion.”Footnote 80 Hence, it was Kant’s goal to show that physics needs to be a priori because the laws of physics apply to all objects without our needing to analyze whether objects actually follow these laws.Footnote 81
The famous dictum of Kant, namely that “[t]houghts without content are empty, [and] intuitions without concepts are blind,”Footnote 82 unfolds as follows:
Our cognition arises from two fundamental sources in the mind, the first of which is the reception of representations (the receptivity of impressions), the second the faculty for cognizing an object by means of these representations (spontaneity of concepts); through the former an object is given to us, through the latter it is thought in relation to that representation (as a mere determination of the mind). Intuition and concepts therefore constitute the elements of all our cognition, so that neither concepts without intuition corresponding to them in some way nor intuition without concepts can yield a cognition.Footnote 83
Roughly speaking, this brings together content by intuition and form by thought. By the former, Kant provides for the possibility that we assume we see a tree when we actually face a tree. The latter provides grounds for things appearing to human beings in the same way.Footnote 84 However, a powerful criticism of this conception was already advanced by Friedrich Heinrich Jacobi in 1787.Footnote 85 If causality is restricted to representations, if causality is a necessary precondition for us to cognize objects, then we cannot assume at the same time that things in themselves exist which affect our receptivity, by which they provoke our impressions. Hence, if causality only belongs to the form of our cognition, the content cannot be brought about by causality as well. We lack force to explain that we see a tree because there is a tree. If we solve this puzzle by ascribing causality to the things in themselves, however, we lack a reason for differentiating things in themselves from our perceptions of them. No matter how we turn, the form–content dualism implodes. Kant needs the thing-in-itself in order to explain the content of representations and to assume receptivity at all. Yet, in order to do so, he has to award properties to the thing-in-itself which do not pertain to it from Kantian premises.Footnote 86 In Jacobi’s words: “I must admit that I was held up not a little by this difficulty in my study of the Kantian philosophy … because I was incessantly going astray on this point, viz. that without that presupposition I could not enter into the system, but with it I could not stay within it.”Footnote 87 In order to avoid this criticism, we could turn to a passage in the Critique of Pure Reason where Kant seems to retreat to a position labelling the thing-in-itself a mere “boundary concept, in order to limit the pretension of sensibility.”Footnote 88 More expansively, Kant stated:
If, therefore, we say: The senses represent objects to us as they appear, but the understanding, as they are, then the latter is not to be taken in a transcendental but in a merely empirical way, signifying, namely, how they must be represented as objects of experience, in the thoroughgoing connection of appearances, and not how they might be outside of the relation to possible experience and consequently to sense in general, thus as objects of pure understanding. For this will always remain unknown to us, so that it even remains unknown to us, so that it even remains unknown whether such a transcendental (extraordinary) cognition is possible at all, at least as one that stands under our customary categories. With us understanding and sensibility can determine an object only in combination. If we separate them, then we have intuitions without concepts, or concepts without intuitions, but in either case representations that we cannot relate to any determinate object.Footnote 89
However, if we accepted this interpretation,Footnote 90 it would be difficult to sustain speaking of things in themselves in the plural.Footnote 91 Finally, while Kant holds that it is synthesis, a process of the cognizing subject, which provides for order and determination, this is hard to sustain becauseFootnote 92 “[a]ll organizational forms immanent to the transcendental consciousness – or within the genome: the logical position of the problem remains strictly identical in the two cases – cannot provide anything if the ‘material’ they are to ‘form’ does not already include in itself the ‘minimal form’ of being formable.”Footnote 93
This leads straightforwardly to another very well-known Kantian counterpart. Georg Wilhelm Friedrich Hegel is another important “early” critic of Kant. Hegel criticized Kant – among other things – for his concept of a “thing-in-itself,” which is found to exist by Kant even though we cannot perceive it.Footnote 94 To Hegel – in close agreement with JacobiFootnote 95 – such a thing-in-itself is a “ghost,” for we cannot say anything about it since Kant, by holding that this thing-in-itself exists, construes a causal relationship between the appearances (Erscheinungen) and the thing-in-itself.Footnote 96 According to Hegel, the thing-in-itself is “itself only the product of thought,”Footnote 97 a “Gedankending.”Footnote 98 Hence, if we think, we are thinking; nothing more and nothing less can be proven by that and thus the thing-in-itself is a product of our thinking and not a thing in the external world.Footnote 99 To put it differently, it is impossible to claim something would exist in the external world which, nevertheless, cannot be proven. Even more bluntly, how could I ever find out whether your version of the thing-in-itself looks like mine? For Hegel, our understanding of knowledge has a history – a history of the whole human being that includes its physiological competence, its social environment, as much as its religious, political and philosophical convictions.Footnote 100 In Hegel’s words, an “aspect of spirit’s coming-to-be, history, is that knowing self-mediating coming-to-be – the spirit relinquished into time.”Footnote 101 In very broad strokes, this is the fundamental difference between Kantian “subjective idealism” and Hegelian “objective idealism.”Footnote 102 Hence, our thinking not only captures subjective constructions, or crude empirical facts, but follows the objective structure of being. In Hegel’s own words, introducing the spirit: “The I that is we and the we that is I.”Footnote 103 It is this switch, departing from a Kantian “I think,” that could be called “methodological solipsism,” finally arriving at a “We think.” This Hegelian unity claims that “analytical unity” can only exist in “synthetic unity.”Footnote 104 Thinking presupposes complex conceptual faculties that can only be acquired in a community. The existence of a subjective spirit presupposes an objective spirit. And, thus, philosophy as much as epistemology has to dismiss “methodological solipsism.”Footnote 105
This is still the very beginning of the nineteenth century. Hence, the “linguistic turn” in philosophy is still to come. Writ large, we can say that whereas Kant aimed at a criticism of pure reason and rational assumptions when thinking about what we can know, after the linguistic turn, the transcendental criticism turned to a critique of language.Footnote 106 This so-called linguistic turn in philosophy, brought about, among others, by Ludwig Wittgenstein, further challenges metaphysical assumptions and is thus also of relevance here.Footnote 107 Wittgenstein makes the argument – as did Hegel – that it is a contradiction to speak about limits of our knowledge (Erkenntnis) because by knowing the limits one has to have transcended the limit already. Without a point of reference external to our knowledge (Erkenntnis) (via our senses, experience or consciousness), we do not have a reason to question the limitlessness of our thinking about objects. In Wittgenstein’s famous saying:
The limits of my language mean the limits of my world.
Logic fills the world: the limits of the world are also its limits. We cannot therefore say in logic: This and this there is in the world, that there is not. For that would apparently presuppose that we exclude certain possibilities, and this cannot be the case since otherwise logic must get outside the limits of the world: that is, if it could consider these limits from the other side also. What we cannot think, that we cannot think: we cannot therefore say what we cannot think.
This remark provides a key to the question, to what extent solipsism is a truth. In fact what solipsism means, is quite correct, only it cannot be said, but it shows itself. That the world is my world, shows itself in the fact that the limits of the language (the language which I understand) mean the limits of my world.
The world and life are one.Footnote 108
Without entering into all the intricacies of Wittgensteinian philosophy in particular,Footnote 109 and the linguistic turn and the “birth” of analytic philosophy in general,Footnote 110 it is nevertheless important for us to understand that a fundamental skepticism relating to things a priori goes hand in hand with this development. While it can, in a way, be described as a transformation from epistemology to the philosophy of science, it is common ground shared by proponents of logical empiricism, such as Moritz Schlick and Rudolf Carnap, and their adversaries from critical rationalism, such as Karl Raimund Popper, that natural laws are not valid a priori.Footnote 111 While the advocates of logical empiricism aim to avoid metaphysics altogether for the sake of science, advocates of critical rationalism accepted metaphysics as being of heuristic value for science.Footnote 112 Beyond that, Popper and Carnap alike deny the possibility of a priori synthetic judgments.Footnote 113
Interestingly, however, Wittgenstein famously ends his Tractatus with the metaphor of a ladder. “[A]nyone who understands” him, Wittgenstein says, “recognizes” his propositions “as nonsensical, when he has used them – as steps to climb up beyond them.”Footnote 114 He then suggests that the reader “throw away the ladder” after having “climbed up it”; his propositions must be transcended to “see the world alright.”Footnote 115 For “[w]hat we cannot speak about we must pass over in silence.”Footnote 116 Thus, again, we are left with a clear warning against metaphysical claims a priori. This, I think, is fair to conclude from this finding.Footnote 117 While this was not the end of philosophy of science and even Wittgenstein himself seemed to have continued climbing,Footnote 118 one message appears to be rather clear-cut. Metaphysical assumptions are a daring venture and if we are to advance something of this sort, utmost prudence and reluctance seems to be in order, and a proper justification for any assumption we consider necessary is indispensable and yet must be regarded with suspicion. What is more, since Kant famously pointed to the need for critical metaphysics, science has made huge advancements, which at least suggest that what Kant tried to establish as granted a priori cannot be defended as given.
In this vein, the criticism advanced by Charles Sanders Peirce is pertinent as he states that he “cannot admit the proposition of Kant – that there are certain impassable bounds to human knowledge.”Footnote 119 This seemed wrong to Peirce because “[t]he history of science affords illustrations enough of the folly of saying that this, that, or the other can never be found out.”Footnote 120 Yet, despite this critique, the so-called founder of pragmatism was an admirer of Kant and indeed can be labeled as a defender of objective idealism despite his pragmatism.Footnote 121
Being aware of the pragmatist approach of Peirce, Karl-Otto Apel developed transcendental pragmatism (Transzendentalpragmatik)Footnote 122 and Jürgen Habermas universal pragmatics (Universalpragmatik).Footnote 123 The former analyzes transcendental – that is, enabling – conditions for human action. The latter, also called “formal pragmatics” by Habermas when he first wrote about it, is conceptualized as “reconstructive science.” The point is to “render theoretically explicit the intuitive, pretheoretical know-how underlying such basic human competences as speaking and understanding, judging and acting.”Footnote 124 Importantly, and “[u]nlike Kant’s transcendental analysis of the conditions of rationality, reconstructive sciences yield knowledge that is not necessary but hypothetical, not a priori but empirical, not certain but fallible.”Footnote 125 By closely focusing on language and conceptualizing “reconstructive science,” Habermas departs in important ways from Kant, which is also relevant to us. For Habermas, philosophy is no longer “the sole judge in normative matters.” What is more, nor is philosophy “the methodological authority that assigns the various domains of inquiry to their proper questions.” In contrast, according to the approach advanced by Habermas, “philosophy must engage in a fully cooperative relationship with the social sciences and the empirical disciplines in general.”Footnote 126 “Once we have dropped foundationalist claims, we can no longer expect a hierarchy of sciences.”Footnote 127 Beyond that, Jürgen Habermas, among others, has also developed a consensus theory of truth.Footnote 128 According to this view, truth is what can be claimed in a noncoercive general and justified consensus. For participants in a rational discourse, we have to assume pragmatic prerequisites, which are a sort of aspiration; in Habermas’ words they are “an unavoidable supposition, reciprocally made in discourse.”Footnote 129
A pragmatic theory of truth, in turn, does not accept the consensus theory of truth and takes practical life – instead of consensus – as a yardstick. According to this view, a proposition is true if its consequence helps solve a practical problem or answer a question related to such a problem.Footnote 130 As has been spelled out before, this cannot be brought in line with the Kantian assumptions as borrowed by the Kelsenian pure theory of law either. Yet this approach too faces criticism that because something is useful does not mean it must be true. False facts, as is proven over and over again, can be very useful. This, however, does not render lies true.
The coherence theory of truth is another major competitor in the question of what is truth.Footnote 131 According to this conception, a proposition is compared to an already established system. Hence, to figure out whether a proposition is true, we need to evaluate whether this proposition can be included in a system without contradiction – in other words, whether this proposition is coherent with the system. This, however, is likely circular or necessitates a preestablished system. Beyond that, coherence is quite a weak criterion for truth. However, importantly for our purpose, it does not support the Kelsenian pure theory of law as it does not help restore what has been lost through the critique of the Kantian assumptions of the Kelsenian project.
Finally, in contemporary epistemology it is important to note Donald Davidson, who also argues that thought hinges on language.Footnote 132 Yet, according to his deflationary theory of truth, the term truth does not denote a real property of sentences or propositions. To him, it is a “folly” to try to define truth,Footnote 133 for it is precisely the point of this theory of truth to prove the irrelevance of its subject matter.Footnote 134
Obviously, this was a strikingly brief overview lacking many important details. However, to return to the reason why we started engaging with epistemology and theories of truth, I think it should have become clear by now that Kantian epistemology, despite its genius, is not a stable foundation for legal epistemology. It is not up to date and has been heavily criticized, and rightly so. Therefore, it is no firm basis for a theory on the relationship between legal orders. For a proper legal epistemology, we cannot but consider the philosophical progress achieved since the eighteenth century.Footnote 135 Nevertheless – leaving the criticism just expressed to one side – we will now take a look at some neo-Kantian defense against criticisms aimed at Kant in particular and neo-Kantian philosophy in general. We will do so in order to determine whether the leap from Kantian to neo-Kantian epistemology can provide fruitful grounds for the axioms of the pure theory of law and Kelsenian legal epistemology, which is the basis for Kelsenian legal monism.
1.2.2 Neo-Kantianism and Its Conception of Epistemology
“It seems to be obvious that great ideas and insights inevitably become dogmatized.”Footnote 136 Kant developed his Critique of Pure Reason and the arguments expressed therein to enable scientific metaphysics. In his Metaphysics of Morals generally and in his Doctrine of Right in particular, for instance, Kant did not return to his epistemology in the sense that the Kelsenian pure theory of law does concerning the law.Footnote 137 What Kant considered as synthetic a priori judgments on epistemology in general – causality, for instance – is quite different from legal validity. Kelsen, however, simply adopted what he labeled a (neo-)Kantian position with regard to the law. So what Kant considered necessary concerning the cognition of the external world and how we perceive nature, Kelsen postulates – without giving reasons for this intriguing analogy – would apply to the regulation of human behavior as well.Footnote 138 Before elaborating on this claim and the problems arising with such an alliance, we will first analyze relevant neo-Kantian positions.
Kantian philosophy was immensely influential and, alongside the criticism partly outlined earlier, some scholars – today commonly referred to as neo-Kantians – answered criticisms of Kant and became well-known for their philosophical battle cry “back to Kant!”Footnote 139 Again, a caveat is in order. As neo-Kantianism is better classified as a rather loose philosophical movement than a specific school of thought, it is impossible to outline all positions and arguments attributed to this label.Footnote 140 Hence, we will again only refer to those arguments that are related to Kelsenian legal epistemology. In this vein, the neo-Kantianism from Marburg, most prominently represented by Hermann Cohen, is of interest to us.Footnote 141 The neo-Kantianism that was located in Baden around Wilhelm Windelband will therefore be left aside here. Yet doubts about the Kelsenian interpretation of Kant might already be supported because he chose not to align with those neo-Kantians who focused on the humanities, namely those located in Baden. Their value-laden approach was actually quite far from what Kelsen was aiming at. This is not in itself a strong argument against the Kelsenian interpretation of Kant. However, it is still interesting that Kelsen claimed to follow those neo-Kantians who were not so much interested in the humanities as in physics and mathematics.Footnote 142
Neo-Kantians did not follow Kantian positions blindly but deviated from Kant in some important respects. This is significant as changes introduced to or criticism expressed of Kantian conceptions by his successors have to be followed closely when claiming to adopt either a Kantian or a neo-Kantian approach. To put it bluntly, cherry-picking has to be treated with caution. For Marburg neo-Kantians, for instance, things in themselves were a postulation and the distinction between sensibility and understanding was rejected too.Footnote 143 Yet they nevertheless considered as essential the “existence of substantive a priori concepts and principles that make knowledge possible,”Footnote 144 though not necessarily those concepts and principles identified by Kant since the scientific theories he referred to were (partly) considered outdated.Footnote 145 What is particular to neo-Kantian philosophy is its proponents’ interest in the scientific methodology and the question of how we can know anything about the different branches of science: in their words, “the logic of the sciences.”Footnote 146
For Cohen in particular, it was important to distinguish philosophy from psychology.Footnote 147 While the former, according to him, aims at objectivity, the latter is utterly subjective.Footnote 148 What Cohen aligns closely with Kant, however, is the “transcendental method,” which, in Cohen’s conception, “begins with a fact – paradigmatically, the fact of science – and investigates the conditions that make that fact possible.”Footnote 149 Interestingly, the Marburgian transcendental method begins with a “fact” that is historically verifiable – a “fact of science” regarding theoretical philosophy and a fact of “social order” concerning practical philosophy.Footnote 150 In a second step, what makes objective validity possible is analyzed from this fact, by identifying the “laws” or “form” of the specific discipline.Footnote 151 The “goal of the transcendental method is to provide foundations for culture” that “are not meant to be certain” and, thus, “[t]ranscendental logic, one might say, is a semantic, not a Cartesian project.”Footnote 152 Beyond that, Marburg neo-Kantians too considered themselves as “idealists,” which is expressed in their transcendental method and their belief in substantive a priori principles that make experience possible. The conception of objectivity “grounded in the idea of the unity of knowledge according to laws” and their philosophy of science, which is held to be “radically unlike the features that the world appears to have to untutored, everyday experience,” also point in this direction.Footnote 153
What becomes apparent from this brief overview of neo-Kantianism is that neo-Kantian philosophers were actually ready to reconsider Kantian positions quite extensively.Footnote 154 For Kant, roughly speaking, Aristotelian logic, Euclidian geometry and Newtonian mechanics were state of the art and thus the laws constituting and enabling our understanding of these approaches were “postulated as valid.”Footnote 155 Neo-Kantians were aware that science advances and therefore the a priori needs to be adapted, even to the extent that they tried to understand and capture the evolution of science as well. By now our knowledge in each field has arguably advanced again noticeably, to put it mildly. What we learn is that maybe Kant was right in a sense that experience and our perception of experience preconditions some sort of form or faculty in us.Footnote 156 Yet what we might potentially consider as “given” has changed with the development of science since Kant thought about it and very likely will change again with further developments in the future.Footnote 157 Hence, it is of utmost importance to be very careful when postulating a given faculty or form as being a precondition for knowledge: “objective validity” in a neo-Kantian sense on the one hand and legal validity on the other. In fact, we should acknowledge that “objective validity” concerning our knowledge of the external world and the legal validity of norms must be kept apart. The law is arguably quite different from any physical object. Therefore, we have to take a close look at how to establish and argue for conditions necessary for legal knowledge.Footnote 158
1.2.3 Kelsenian Legal Epistemology
Hans Kelsen claimed that his pure theory of law in the form of its basic norm is a priori necessary in order to cognize any legal order.Footnote 159 And so those who follow Kelsen are likely to elaborate on the “transcendental undergirding for legal science.”Footnote 160 Kelsen asks, “how is positive law qua object of cognition, qua object of cognitive legal science, possible?”Footnote 161 Thereby he aims at establishing a “legal a priori” in the sense of Kant’s “transcendental a priori.”Footnote 162
In this vein, Kelsen’s clear vision to uphold the is–ought dichotomy is also of interest.Footnote 163 To him, law – the ought – is one thing, and the is – politics, psychology, sociology, morality – is something to be held clearly distinct.Footnote 164 In fact, this is the essence of his quest for purity. As describing and prescribing are acts to be held apart,Footnote 165 the science of law must be distinguished from natural and other sciences.Footnote 166 As with causality, Kelsen claims, legal validity also must find its final source. In his words, the “search for the reason of a norm’s validity … must end with a norm which, as the last and highest, is presupposed.”Footnote 167 And thus “[s]uch a presupposed higher norm is referred to in this book as basic norm.”Footnote 168 This, importantly, is connected with the claim that the validity of one norm can only derive from another norm.Footnote 169 It is of particular interest for our purpose that precisely this feature of the Kelsenian pure theory of law, and thus also of Kelsenian legal monism, is referred to as “Kelsen’s reply to the juridico-transcendental question.” It is claimed that this stipulation is “[i]n a similar fashion to Kant’s ‘Copernican revolution’ through which he realized that a priori (i.e. necessary) knowledge is not possible by conforming intuition to the nature of objects, but by conforming the object to our intuition.”Footnote 170 And almost in the same breath we learn that “the true status of the basic norm” is “a neo-Kantian transcendental notion and answer to the … juridico-transcendental question in the sense of Hermann Cohen’s philosophy.”Footnote 171
These propositions are claimed to be made following Hermann Cohen, and hence are claimed to be in accordance or at least reconcilable with the so-called neo-Kantian school from Marburg.Footnote 172 One idea of neo-Kantianism was to transport Kantian epistemology, which was mainly directed at the natural sciences, to other disciplines. The point was to discover the necessary preconditions of science (and thereby to confront empiricismFootnote 173 or, in positive terms, to emphasize the scientific nature of philosophy).Footnote 174 Nevertheless, friction is unavoidable when transplanting to the field of law and legal science ideas that were originally expressed with regard to natural sciences and knowledge in general and the external world in particular.Footnote 175 To Kelsen, it was obviously clear that law is a system of norms made by human beings for human beings.Footnote 176 In his words, “when we compare the objects that have been designated by the word ‘law’ by different peoples at different times, we see that all these objects turn out to be orders of human behavior.” An “order,” he goes on, “is a system of norms whose unity is constituted by the fact that they all have the same reason for their validity; and the reason for the validity of a normative order is a basic norm … from which the validity of all norms of the order are derived.”Footnote 177 Within a Kantian tradition one thus has to argue why one thinks that scientific metaphysics, in other words a transcendental method, is considered necessary for cognizing the law. Kant himself apparently did not think it was.Footnote 178 Arguments are necessary for why the law, too, has a priori law-specific attributes.Footnote 179 Mere postulations that only then could law be cognized in a “pure way” are not sufficient as such claims result in a vicious metaphysical circle. Moreover, when following the Marburg neo-Kantian tradition, it is important to explain why this school of neo-Kantianism, more focused on the natural sciences, was chosen instead of the Badian approach focused on humanities. In addition, when following a neo-Kantian tradition, it is important to set out the social fact that has to be identified first. Only from this fact, in a second step, can objective validity be constituted according to neo-Kantianism, as briefly outlined above.Footnote 180 Moreover, this fact needs to be historically verifiable. Merely claiming that the term “law” has always turned out to be an order of human behavior determined “by different peoples at different times”Footnote 181 is rather weak in this regard.Footnote 182 In addition, neo-Kantians understood themselves as idealists. It does not seem that such a classification would be accepted by Kelsenians. Rather, I suspect they would claim that their only idealization would be the purity of the law.
Beyond that, it is notable that Kelsen himself stated that no one can be forced to use the basic norm as a scheme to interpret the law.
[A]n anarchist, for instance, who denied the validity of the hypothetical basic norm of positive law (theoretical anarchism always somehow shares the position of natural law, the theory of pure natural law that of anarchism), will view its positive regulation of human relationships (such as property, the hiring contract) as mere power relations and their description as “ought” norms a mere “fiction,” as an attempt to supply a justifying ideology.Footnote 183
This example shows that the Kelsenian basic norm is not a necessary condition for thinking about the law in a transcendental Kantian sense,Footnote 184 as the anarchist cognizes the very same act as, for instance, the police force. However, as Kelsen claims, to the anarchist this is not the law in action but brute illegitimate force. This understanding nourishes doubts that the Kelsenian position might collapse into a solipsistic understanding of the law where the subjective perception of the anarchist melts into the object – that is, the act he or she is cognizing. This even goes so far as Kelsen himself stating that international life might only be cognized via anarchy guided by power (instead of through a basic norm and thus monism with the primacy of international law, for instance).Footnote 185 If this is the case, however, how can we be sure that every lawyer will use this scheme? And, more importantly, if this is a personal decision depending on the Kantian assumption as referred to earlier, how can we ever be sure that this scheme is shared by different legal scholars, different legal cultures and so on? I submit that we cannot, especially if we remember the criticism advanced against the Kantian position by several philosophers, accusing it of falling short of solipsism.Footnote 186 Hence, if we take a skeptical stance towards the Kantian position and consider a development by Arthur Schopenhauer stating that “every man takes the limits of his own field of vision for the limits of the world,”Footnote 187 this critique becomes all the more pressing. Hence, due to the Kantian assumptions, the critique these assumptions face, and these thoughts advanced by Kelsen himself, we have to classify the Kelsenian pure theory of law and its basic norm as “legal theoretical solipsism.”Footnote 188 This critique might be responded to with a rather thick shared transcendental understanding of what legal validity and, hence, the law actually are. If we presumed such a thick legal a priori as given to any lawyer, we could establish a response to the legal solipsism reproach. This, however, becomes even more troublesome as it brings us into legal metaphysics – something that the pure theory of law claims to avoid. This critique is also illuminating. We can conclude that the more we aim for purity, the more we need to consult a priori legal knowledge. Only then can we ensure that lawyers will use the same scheme when interpreting the law.
Finally, with regard to neo-Kantianism, it has to be said that this philosophical movement was popular from around 1870 until the First World War.Footnote 189 The briefly outlined further developments, particularly concerning the linguistic turn in philosophy and epistemology alike, must be taken into account when a historical epistemological account such as Kantian or neo-Kantian epistemology is advocated in the twenty-first century.Footnote 190 And, in more general terms, there are philosophical voices stating that we cannot even be sure that we are not simply a computer simulation controlled by an advanced human society.Footnote 191 It is hard to establish certainty concerning a guarantee that what I see as what is there and what you see as what is there actually is there and that our perceptions are comparable. We need to account for that in our theoretical thinking if we want to fulfil scientific standards of philosophical thinking and argument. Yet the law is quite a special scientific discipline. Law’s normativity is puzzling. It is hard to separate a description of facts and a prescription of how to act. Despite these difficulties, it is very likely a theoretical overload to mix these questions with epistemological puzzles.
Astonishingly, we can find arguments by convinced and well-established scholars who commit themselves to the pure theory of law, stating that even if Kant or neo-Kantians actually had a different project in mind or are simply misrepresented by the Kelsenian pure theory of law, this would not be a serious problem for the pure theory of law.Footnote 192 According to them, Kelsenian pure theory stands alone and even epistemological “realists” “today” (writing in 1991) would concede that knowledge (Erkenntnis) necessarily presupposes a combination of judgments a priori and a posteriori.Footnote 193 It is conceded that this understanding, which, certainly reflects an important insight, is nevertheless understood differently by the “realists” referred to above.Footnote 194 They consider the statement that the manner of cognizance constitutes the object not as a transcendental necessity, but as a consequence of scientific methodological procedure which entails – and this is by no means unimportant – that the methodology applied partly constructs the object. Therefore, science must use rigorous methodology. This, in turn, has the consequence that the methodology can and, depending on the progress of science, must be adapted. That the act of choosing a specific methodology has normative implications and must be appropriate is conceded by Kelsenian legal scholarsFootnote 195 but without drawing the correct conclusions from doing so. On the contrary, this is taken as another confirmation of the pure theory of lawFootnote 196 (and at the same time used to dismiss a contested view of analyzing the Austrian federal state as done by Peter Pernthaler, Theo Öhlinger, Karl Weber and othersFootnote 197).
The law is quite different from the question of what constitutes knowledge about the external world and how we acquire it. The law is simply a tool for organizing our social life. Thus, in the same way as it is not important for our daily life to reflect on whether a tiger we perceive as standing in front of us really is there (on the contrary, this is probably a bad moment to reflect on the existence of the external world), it is not of primary importance to reflect on what the law “actually” is and whether it “really” exists. Law is a practical tool. Whether law is good or bad depends to a considerable extent on whether it works or not – whether it is efficient. This was even acknowledged to some extent by Hans Kelsen.Footnote 198 Thus, it is very likely not the best choice to base our understanding of the law on a rather solipsistic understanding of epistemology holding that the method of cognizance fully constitutes the object of cognizance.
Law asks for a practical understanding of epistemology. To the same extent that I am satisfied if I ask you to bring me a red T-shirt and you – no matter what you perceive as red – manage to bring me a T-shirt that satisfies my “redness expectation,” it is enough for our legal life that what we perceive as law is able to account for an intersubjective organization of social life.Footnote 199
What it boils down to is that the Kelsenian pure theory of law and thus also Kelsenian monism is not a necessary condition for thinking about the law. It is a mere invitation to set up specific axioms to talk about law in a specific way. It has been and still is a radical way to claim that only this very specific way of thinking about the law can be called proper or pure legal scholarship, because this claim necessarily entails that if you do not agree on the axioms you are not doing legal science. You can do so as much as you are free to play tennis at the weekend in your leisure time, but when you want to talk about law at university, you must accept the axioms. This is quite a hostile way of doing science. However, due to its sharp contrast and its radicality it has attracted a lot of attention. The critique advanced here is, to repeat myself, not a blatant rejection of thinking and speaking like this about the law. However, the abovementioned criticism has made clear that, so far, no one has proven why the axioms chosen by the pure theory of law should be the only necessary conditions for thinking about the law. They were merely postulated. From this it follows that they are not hardwired in our brains as some sort of innate legal faculty; nor are they other commonly achieved preconditions for cognizing the law. It is simply an offer you can accept, which, on acceptance, provides you – admittedly – with a clear-cut language (with all its advantages and disadvantages). From this it follows, however, that you can also decline this offer, establish another methodology and still think and speak about the law.
In fact, the Kelsenian pure theory of law bears resemblance to a religion.Footnote 200 You can believe in it, or not. The high priests and true believers of Kelsenianism might tell you that this is the only truth and that there is no other true system of law. However, the mere existence of other religions with competing claims about the purpose of legal life and its claimed eternity simply show that this is one of many possible ways to think about the law. Moreover, the criticism advanced above forces us to draw the conclusion that it is not the most convincing way. In another metaphor, it is important to know the vocabulary of the Kelsenian language if you want to talk meaningfully to a Kelsenian. Yet it is by no means the only true legal language in the legal world. From this it follows that the claim that everything that is expressed in Kelsenian legal language represents legal science and, conversely, anything else is unscientific – or probably representing sociology, morality, but definitively not within the realm of legal science – is rather bold and should be rejected.Footnote 201
1.2.4 Kelsenian Monism and the Solution of Norm Conflicts between Legal Orders
Leaving the critique advanced against Kelsenian epistemology to one side, let us assume that we can accept the epistemological basis of legal monism. If we do so, we still need to provide arguments for why and how Kelsenian monism is superior when explaining the relationship between legal orders in general, and when looking for a convincing solution to norm conflicts in particular. Concerning the latter, Kelsen claims that the solution to norm conflicts between different legal orders follows “logically” from the theoretical stance of Kelsenian monism. This, however, faces a serious restriction due to its Kantian basis:
Yet such a principle [of systematicity] does not prescribe any law to objects … but rather is merely a subjective law of economy for the provision of our understanding, so that through comparison of its concepts it may bring their universal use to the smallest number, without justifying us in demanding of objects themselves any such unanimity as might make things easier for our understanding or help it extend itself, and so give objective validity to its maxims as well.Footnote 202
Against this background, it is notable that the norm conflict between “different systems of norms” is construed as a legal epistemological impossibility in Kelsenian legal monism.
[T]he assumption of two truly different systems is revealed as false. If there should be two actually different systems of norms, mutually independent in their validity … both of which are related to the same object (in having the same sphere of validity), insoluble logical contradiction could not be excluded. The norm of one system may prescribe conduct A for a certain person, under a certain condition, at a certain time and place. The norm of the other system may prescribe, under the same conditions and for the same person, conduct non-A. This situation is impossible for the cognition of norms.Footnote 203
This is a rather astonishing thesis as it seems that, yet again, the a priori prerequisites are rather overloaded. It is thus important to take a closer look at this claim as well.Footnote 204 In cases of norm conflict, the monistic doctrine needs to deal with the question of which jurisdiction prevails – international or national law, and now international, EU or national law. However, a monistic doctrine with the so-called primacy of national law must be traced back to a highly nationalistic view of international law, which no longer can be considered suitable.Footnote 205 In other words, how could popular sovereignty in the form of national law (and thus one people only) rule over international or EU law without denying the validity of international or EU law? How should the validity of, say, EU law be based on the popular sovereignty of a single Member State’s legal order and the popular sovereignty of one nation instead of all Member States’ legal orders and their respective nations?Footnote 206 The failure of the monistic conception of the primacy of municipal law to answer these questions is left aside here.
Monism with the primacy of international law has attracted a lot more attention. In order to justify the primacy of international law, the monistic doctrine stipulated the premise of a hypothetical unity – being kept together by the “chain of validity.”Footnote 207 The ultimate foundation of validity is Hans Kelsen’s famous basic norm briefly touched on above.Footnote 208 It is a concept that accounts for the unifying foundation of law and its validity.Footnote 209 The basic norm is an attractive but problematic concept, which has found many diverging interpretations by admirersFootnote 210 and critics alike.Footnote 211 The concept of the “chain of validity” is even more troublesome.Footnote 212 Kelsen holds that
[a] norm of general international law authorizes an individual or a group of individuals on the basis of an effective constitution, to create and apply as a legitimate government a normative coercive order. That norm [of general international law], thus, legitimates this coercive order [of a “state” in the meaning of international law] for the territory of its actual effectiveness as a valid legal order and the community constituted by this coercive order as a “state” in the sense of international law.Footnote 213
Similarly, Verdross argues from the viewpoint of an international basic norm – which in Verdross’ conception is pacta sunt servandaFootnote 214 – from which municipal law also derives: “The freedom of States is nothing else than a margin of discretion depending on international law.”Footnote 215 According to him, the lawmakers of public international law are not States, but the international community, acting through an international organ with supranational power.Footnote 216
Following this idea that norms can only derive from other norms, the conclusion drawn would have to be that any national law is derived from EU law, and EU and national law derive from international law. This, however, is an argument that does not reflect reality.Footnote 217 Indeed, the CJEU famously postulated the “autonomy of the Community legal order”Footnote 218 and introduced the “direct effect”Footnote 219 of EU law, which has been interpreted by some as a monistic approach.Footnote 220 Nevertheless, even for the most progressive EU constitutional lawyers it would be a step too far to argue that all Member State legal orders derive from EU law. Without the backup of the epistemological necessity of such claims, the postulation of such a chain of validity is exposed as the Emperor’s new clothes: “But he has not got anything on!”Footnote 221
The fatal blow for monism with regard to EU law is the relationship between EU law and international law, which appears to show even dualistic elements.Footnote 222 This “Janus face” is a challenge for the unifying concept of Kelsenian monism – at least when trying to uphold its underlying assumptions to explain this reality. Hence, also concerning the relationship between international and EU law, Kelsenian monism faces a reality that challenges its theoretical assumptions. How can the relationship between international and EU law be explained as a unity by Kelsenian monism if the CJEU clearly conceives these two legal orders as being separate? Again, without the epistemological necessity of Kelsenian monism, this postulation becomes utterly fictitious and therefore is not a superior explanation of the relationship.Footnote 223
1.3 Why Dualism and Kelsenian Monism Do Not Resolve the Question of Who Has the Final Say
While it is important to consider the current dichotomy of legal sources of international, EU and national law, a common normative framework is equally important. Such a framework is necessary to acknowledge the entanglements of these three legal orders and to enable a solution to the norm conflicts arising from this entanglement. Hence, the changes in the legal landscape force us to leave behind the almost 100-year-old theories of monism and dualism. Major developments force us to seek an adequate theoretical framework that fits the reality of our time.
The main claims of dualism and monism are summarized in Table 1.1.