In a brief autobiographical note, Friedrich Hayek refers to the influence he had received in his younger years from both his teacher Ernst Mach and his distant cousin Ludwig Wittgenstein:

“But I did, through these connexions, become probably one of the first readers of Tractatus when it appeared in 1922. Since, like most philosophically interested people of our generation I was, like Wittgenstein, much influenced by Ernst Mach, it made a great impression on me.”

F. A. Hayek – Remembering My Cousin, Ludwig Wittgenstein

This can be seen in the analytical rigor present in his essays published in the 1920s and in his book Monetary Theory and the Trade Cycle (Geldtheorie und Konjunkturtheorie) (1929), translated by N. Kaldor and H. M. Croome from the German. However, such influence was not exclusively limited to Hayek’s youth. He was also present in the conception and writing style of The Sensory Order, published in 1952, and Law, Legislation and Liberty, the first volume of which, Rules and Order, was published in 1973.

From my point of view, the following aphorism of the Tractatus Logico-Philosophicus is the one that best allows us to appreciate the reflection of said work in Hayek:

4.12 „Der Satz kann die gesamte Wirklichkeit darstellen, aber er kann nicht das darstellen, was er mit der Wirklichkeit gemein haben muß, um sie darstellen zu können -die logische Form.

Um die logische Form darstellen zu können, mußten wir uns mit dem Satze außerhalb der Logik aufstellen können, das heißt außerhalb der Welt.“

Which could be translated as follows:

4.12 “The proposition can represent the whole of reality, but it cannot represent what it must have in common with reality to be able to represent it – the logical form.

To represent the logical form, we should have to be able to station ourselves with the proposition somewhere outside the logic, i.e.: outside the world.”

This statement about the limits of representation later finds its correlation in the following aphorisms from Hayek’s The Sensory Order, about the limits of knowledge and of the transmission of information:

8.14. While there can thus be nothing in our mind which is not the result of past linkages (even though, perhaps, acquired not by the individual but by the species), the experience that the classification based on the past linkages does not always work, i.e., does not always lead to valid predictions, forces us to revise that classification (6.45-6.48). In the course of this process of reclassification we not only establish new relations between the data given within a fixed framework of reference, i.e., between the elements of given classes: but since the framework consists of the relations determining the classes, we are led to adjust that framework itself.

Note that if there is something that “does not always work,” then we are confronted with the limits to our representation. I think that the said “framework of reference” could play the role of the “logic form” and what Hayek is describing here is the dynamics of a negative feedback process.

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8.18. The new experiences which are the occasion of, and which enter into, the new classifications or definitions of objects, is necessarily presupposed by anything which we can learn about these objects and cannot be contradicted by anything which we can say about the objects thus defined. There is, therefore, on every level, or in every universe of discourse, a part of our knowledge which, although it is the result of experience, cannot be controlled by experience, because it constitutes the ordering principle of that universe by which we distinguish the different kinds of objects of which it consists and to which our statements refer.

Here, the subject, instead of being outside the world is inside another universe of discourse.

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8.67. Apart from these practical limits to explanation, – which we may hope continuously to push further back, there also exists, however, an absolute limit to what the human brain can ever accomplish by way of explanation—a limit which is determined by the nature of the instrument of explanation itself, and which is particularly relevant to any attempt to explain particular mental processes.

Nevertheless, there are certain universes of discourse that human beings can never access to -so, they are outside their world.

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8.69. The proposition which we shall attempt to establish is that any apparatus of classification must possess a structure of a higher degree of complexity than is possessed by the objects which it classifies; and that, therefore, the capacity of any explaining agent must be limited to objects with a structure possessing a degree of complexity lower than its own. If this is correct, it means that no explaining agent can ever explain objects of its own kind, or of its own degree of complexity, and, therefore, that the human brain can never fully explain its own operations. This statement possesses, probably, a high degree of prima facie plausibility. It is, however, of such importance and far-reaching consequences, that we must attempt a stricter proof.

Here, Wittgenstein’s logic form delimits the said structures of a higher degree of complexity which the subject given in a simpler universe of discourse could never trespass.

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8.81. The impossibility of explaining the functioning of the human brain in sufficient detail to enable us to substitute a description in physical terms for a description in terms of mental qualities, applies thus only in so far as the human brain is itself to be used as the instrument of classification. It would not only not apply to a brain built on the same principle but possessing a higher order of complexity, but, paradoxical as this may sound, it also does not exclude the logical possibility that the knowledge of the principle on which the brain operates might enable us to build a machine fully reproducing the action of the brain and capable of predicting how the brain will act in different circumstances.

8.82. Such a machine, designed by the human mind yet capable of ‘explaining’ what the mind is incapable of explaining without its help, is not a self-contradictory conception in the sense in which the idea of the mind directly explaining its own operations involves a contradiction. The achievement of constructing such a machine would not differ in principle from that of constructing a calculating machine which enables us to solve problems which have not been solved before, and the results of whose operations we cannot, strictly speaking, predict beyond saying that they will be in accord with the principles built into the machine. In both instances our knowledge merely of the principle on which the machine operates will enable us to bring about results of which, before the machine produces them, we know only that they will satisfy certain conditions.

Thus, the knowledge of the principle enables us to build an abstract machine such as language, the price system, or the law, in order to form expectations of future human actions. Since such abstract machine would be built using the knowledge of the principle, it would not be deliberated designed but grown from the experience.

While Ludwig Wittgenstein confronted the subject of knowledge against the limits of the conceptual representation and threw him into the silence and into the realms of mysticism, Friedrich Hayek, on the other hand, chooses to place the said limit instance in an order of discourse more complex than the human mind, which could be the market, the language itself, or the extended society.

For Hayek, the social order works as an abstract machine, which continuously processes information and appears in the event horizon of the subjects to confirm or readjust their own classificatory systems. These classificatory systems that, in an abstract plane, each individual has and that are in a continuous process of readjustment based on the novelties that come from the spontaneous order, are abstract but, at the same time, empirical.

Among such abstract orders are the normative systems and the first volume of Law, Legislation and Liberty is devoted to their study.

‘Learning from experience’, among men no less than among animals, is a process not primarily of reasoning but of the observance, spreading, transmission and development of practices which have prevailed because they were successful-often not because they conferred any recognizable benefit on the acting individual but because they increased the chances of survival of the group to which he belonged. The result of this development will in the first instance not be articulated knowledge but a knowledge which, although it can be described in terms of rules, the individual cannot state in words but is merely able to honour in practice. The mind does not so much make rules as consist of rules of action, a complex of rules that is, which it has not made, but which have come to govern the actions of the individuals because actions in accordance with they have proved more successful than those of competing individuals or groups.”, Chap. 1, Reason and Evolution

Here we find a process of natural selection of rules of conduct, thus, provided not by representational reason, but from experience.

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The first of these attributes which most rules of conduct originally possessed is that they are observed in action without being known to the acting person in articulated (‘verbalized’ or explicit) form. They will manifest themselves in a regularity of action which can be explicitly described, but this regularity of action is not the result of the acting persons being capable of thus stating them. The second is that such rules come to be observed because in fact they give the group in which they are practised superior strength, and not because this effect is known to those who are guided by then. Although such rules come to be generally accepted because their observation produces certain consequences, they are not observed with the intention of producing those consequences-consequences which the acting person need not know.  Chap. 1, Reason and Evolution

Here we find a concept that Hayek will use extensively along the rest of Law, Legislation and Liberty, the articulated and the unarticulated. In the terms previously used in The Sensory Order, the unarticulated is what belongs to another universe of discourse, of a more complex level.

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The process of a gradual articulation in words of what had long been an established practice must have been a slow and complex once the first fumbling attempts to express in words what most obeyed in practice would usually not succeed in expressing only, or exhausting all of, what the individuals did in fact take into account in the determination of their actions. The unarticulated rules will therefore usually contain both more and less than what the verbal formula succeeds in expressing. On the other hand, articulation will often become necessary because the ‘intuitive’ knowledge may not give a clear answer to a particular question. The process of articulation will thus sometimes in effect, though not in intention, produce new rules. But the articulated rules will thereby not wholly replace the unarticulated ones, but will operate, and be intelligible, only within a framework of yet unarticulated rules. Chap. IV, The Changing Concept of Law

Thus, the process of articulation of new rules is not a labor of creation of new ones, but of discovering them through the limits of the universe of discourse of the individuals.

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The contention that a law based on precedent is more rather than less abstract than one expressed in verbal rules is so contrary to a view widely held, perhaps more among continental than among Anglo-Saxon lawyers, that it needs fuller justification. The central point can probably not be better expressed than in a famous statement by the great eighteenth-century judge Lord Mansfield, who stressed that the common law ‘does not consist of particular cases, but of general principles, which are illustrated and explained by those cases’. What this means is that it is part of the technique of the common law judge that from the precedents which guide him he must be able to derive rules of universal significance which can be applied to new cases.

The chief concern of a common law judge must be the expectations which the parties in a transaction would have reasonably formed on the basis of the general practices that the ongoing order of actions rests on. In deciding what expectations were reasonable in this sense he can take account only of such practices (customs or rules) as in fact could determine the expectations of the parties and such facts as may be presumed to have been known to them.

And these parties would have been able to form common expectations, in a situation which in some respects must have been unique, only because they interpreted the situation in terms of what was thought to be appropriate conduct and which need not have been known to them in the form of an articulated rule. Chap. IV, The Changing Concept of Law

Here, “rules of universal significance” should be understood as knowledge of the principle. The general practices denote that the said order, despite of being abstract, is, nevertheless, empirical. The common expectations are readjusted through a process of articulation of rules which redefine the universe of discourse of the individuals of a given community or society.

This conception of rules allows us to a better comprehension of the notion of natural rights, since they are empirical, despite their enforcement:

Whether we ought to call ‘law’ the kind of rules that in these groups may be effectively enforced by opinion and by the exclusion from the group of those who break them, is a matter of terminology and therefore of convenience. For our present purposes we are interested in any rules which are honoured in action and not only in rules enforced by an organization created for that purpose.

It is the factual observance of the rules which is the condition for the formation of an order of actions; whether they need to be enforced or how they are enforced is of secondary interest. Factual observance of some rules no doubt preceded any deliberate enforcement. The reasons why the rules arose must therefore not be confused with the reasons which made it necessary to enforce them. Chapter V. Nomos: The Law of Liberty.

Finally, despite being the enforcement of natural rights a matter which depends upon a political decision, the authority is a subsystem inside of the same level of discourse of the individuals of the same political order. Thus, the political authority could not trespass the limits of the knowledge of the said empirical order without consequences concerning its stability. It should deal with the rules which act as the framework of individual interaction using just knowledge of the principles, articulated in general and abstract rules. As we succinctly have seen, the youth influence of Ludwig Wittgenstein on Friedrich Hayek endured until the last books of the latter. I dare not say that the Tractatus encloses the clues of interpretation of the most intricated works of F. A. Hayek, but its reader will find some common ground upon which to build a more prolific interpretation of his legacy.