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Nelson, Leonard (1882–1927)


Leonard Nelson, a German critical philosopher and the founder of the Neo-Friesian school, was born in Berlin. After studying mathematics and philosophy he qualified for teaching as a Privatdozent in the natural science division of the philosophical faculty at Göttingen in 1909. In 1919 he was appointed extraordinary professor.

The Critical School

Nelson's philosophical work was concerned mainly with two problems: the establishment of a scientific foundation for philosophy by means of a critical method and the systematic development of philosophical ethics and philosophy of right and their consequences for education and politics.

Nelson's search for a strictly scientific foundation and development of philosophy soon led him to critical philosophy. Nelson took the Critique of Pure Reason to be a treatise on method and regarded the critical examination of the capacities of reason as its decisive achievement. Through this critique alone could philosophical concepts be clarified and philosophical judgments traced back to their sources in cognition. Therefore, Nelson undertook a close examination of the thought of Jakob Friedrich Fries (17731843), the one post-Kantian philosopher who had concentrated on Immanuel Kant's critical method, carried it further, and tried to clarify its vaguenesses and contradictions.

While Nelson was still a student, he began to collect Fries's writings. These were not easily available, for Fries was hardly known at that time; when he was mentioned at all in philosophical treatises, it was as the representative of an outmoded psychologism. In his own first works Nelson attempted to defend Fries against this reproach. Together with a few friends whom he had interested in Fries's philosophy, he began to publish a neue Folge (new series) of Abhandlungen der Fries'schen Schule in 1904the same year in which he wrote his doctoral dissertation on Fries. A few years later he founded, together with these same friends, the Jakob-Friedrich-Fries-Gesellschaft to promote the methodical development of critical philosophy.

Critical Method and Critique of Reason

In his own writings devoted to the critical method, Nelson distinguished between the critique of reason and two misinterpretations of it, transcendentalism and psychologism. The critique of reason was to prepare the grounds for a philosophical system and to give this system an assured scientific basis by means of a critical investigation of the faculty of cognition. Posing the problem in this way seems to require the critique of reason and the system of philosophy to be adapted to each other in such a way that either the critique of reason must be developed a priori as a philosophical discipline, because of the rational character of philosophy, or philosophy must be conceived as a branch of psychology, since the investigation of knowledge by means of the critique of reason belongs to psychology. Transcendentalism sacrifices the main methodical thesis of the critique of reason, that the highest abstractions of philosophy cannot be dogmatically postulated but must be derived from concrete investigation of the steps leading to knowledge. Psychologism fails to recognize the character of philosophical questions and answers, which is independent of psychological concepts.

Kant did not unequivocally answer the question whether the critique of reason should be developed as a science from inner experience of one's own knowledge or as a philosophical theory from a priori principles. His subjective approach, according to which philosophical abstractions should be introduced by a critique of the faculty of cognition, indicates the first interpretation, but in carrying out his investigationsand in the asserted parallelism between general and transcendental logic as well as in the demand for a transcendental proof of metaphysical principlesKant tacitly assumed the second interpretation and interpreted the theorems of the critique as a priori judgments. Fries, who was mainly concerned with countering the contemporary tendency to develop Kant's teaching in the direction of transcendentalism, took the subjective approach and developed it consistently from inner experience, without, however, transforming philosophical questions and answers into psychological ones. The boundary between Fries's work and psychologism is not so clear, and for this reason most of his critics misunderstood his philosophy as a psychologistic system, albeit not a consistent one.

Nelson solved the problem that philosophy based on the critique of reason seemed necessarily to lead either to transcendentalism or to psychologism by proving that both tacitly assume that a basis of knowledge must consist of proving philosophical principles from theorems of the critique of reason. If the theorems of the critique and the foundations of the philosophical system were in fact related to each other in the same way that the premises and conclusions of logical problems are related, then indeed the critique of reason and philosophy would have to be identicalthat is, they would both have to be either empirical and psychological or rational and a priori. By investigating the problem of the critique of reason Nelson showed that and why this premise is mistaken: The critique serves to clarify one's understanding of the origin of philosophical notions and of their function in the human cognition of facts. Cognition is an activity of the self, motivated by sensual stimulation; data acquired by sensual stimulation are related to one another by cognition of the surrounding world. The function of the critique of reason is to demonstrate the connecting ideas in this process and the assumed criteria by which these ideas are applied by analyzing the concrete steps in cognition and to follow these connecting ideas back to their origin in the cognitive faculty by means of psychological theory; it is not its function to prove the objective validity of the principles in which these criteria are expressed. These principles themselves are of a philosophical rather than a psychological nature. They cannot be derived from the statements of the critique; indeed, since they are the basic assumptions of all perception, they cannot be derived from any judgments more valid than they are.

critique of reason and philosophy

The connection between the critique of reason and the system of philosophy, according to this theory, is not one of logical proof; it is derived, rather, from "reason's faith in itself," as Fries put it, from the fact that all striving for knowledge assumes faith in the possibility of cognition. This faith is faith in reason, inasmuch as reason is the faculty of cognition instructed by the stimulation of the senses. This faith is maintained by the agreement of cognitions, but it cannot be further checked or justified by a comparison of cognitions with the object cognized. This sets an unsurpassable limit to the provability of cognitions. Nelson expressed this in his paper on the impossibility of the theory of knowledge, in which he understood the theory to be an attempt to investigate scientifically the objective validity of cognition. In contrast, the critique of reason should limit itself to investigating the direction in which faith in cognition is in fact turned.

In carrying out this investigation Fries and Nelson distinguished between indirect cognition, supported by some other claim to truth, and direct cognition, which simply claims the faith of reason and which therefore neither needs nor has any justification, even when it is obscure and enters consciousness only in its application as a criterion for the unity of sensually perceivable isolated cognition. Fries and Nelson, in agreement with Kant, considered the criteria which belong solely to reason to include the pure intuition of space and time and their metaphysical combinations according to the categories of substance, causality, and reciprocal action.

natural philosophy

Nelson's interpretation of cognition led him to the problem of a mathematical natural philosophy that had been sketched by Kant and further developed by Fries; this philosophy established a priori an "armament of hypotheses" for the empirical-inductive investigation of natural laws. It coincided in fact with the basic principles of classical mechanics and thereby came into conflict with modern physics. Nelson neither minimized this conflict nor confused it with problems of the principles of critical natural philosophy. He saw physics as being in the process of a radical changeover to modern theories, which had by no means yet been ordered into a conflict-free system comparable to that of classical physics. He was sure that every physical theory must go beyond the data provided by observation and experiment in developing concepts and making assertions. And he was convinced that the positivistic, antimetaphysical tendencies of contemporary physicists promoted a tacit and therefore uncritical metaphysics. Without himself being able to solve the conflict that had arisen within critical philosophy, he was convinced the progressive clarification of modern theories would lead back to a physics based on classical mechanics.

Critical Ethics

basic principles

Nelson systematically applied the critical method in his studies in practical philosophyethics in the broadest sense of the word, including philosophy of right and philosophically based educational and political theory. He added his own critique of practical reason to those of his predecessors. He developed his own processes, both for what he called abstraction (analysis of the assumptions underlying practical ethical value judgments) and for determining, by an empirical study of value judgments, "the interests of pure practical reason," that is, ethical demands put to the human will by reason itself. It is these interests that make value judgments possible. Nelson derived two basic ethical principles from these interests: the law of the balanced consideration of all interests affected by one's own deeds and the ideal of forming one's own life independently, according to the ideas of the true, the beautiful, and the good. These two principles were linked by the fact that, on the one hand, the law of balanced consideration, as a categorical imperative, determines the necessary limiting condition for the ideal value of human behavior; on the other hand, the ideal of rational self-determination leads to the doctrine of the true interests of man and finds in these interests the standard for a balanced consideration of conflicting interests.

nelson's system

From these two principles alone Nelson developed his system of philosophical ethics; he limited himself to such consequences as could be derived from these principles purely philosophicallywithout the addition of experiencebut he attempted to grasp them completely and systematically. In this he was influenced, first, by his interest in systematically and strictly justifying the assumptions used in every single step and the logical connections of the concepts appearing in the principles and, second, by his interest in applying this practical science. The principles demonstrated are formal and permit determination of concrete ethical demands only through their application to given circumstances as justified by experience. But it is precisely this application of the principles to the world of experience that requires preparatory philosophical investigation if the application is to be guarded against hasty generalization of single results, in which changing circumstances are not taken into account, and against opportunistic adaptation to circumstances without regard for the practical consequences of ethical principles. In the system as a whole, ethics and philosophy of right appear side by side. Nelson distinguished between them according to different ways of applying the law of balanced consideration. As a categorical imperative, this law demands of the human will the balanced consideration of other persons' interests affected by its actions. By its content it determines the duties of the individual by the rights others have with regard to him; in this respect it is related to communal life and thereby provides a criterion for the value of a social order. Nelson defined this criterion as the concept of the state of right, by which he meant the condition of a society in which the interests of all members are protected against wrongful violation. Ethics, by this definition, is concerned with the duties of the individual; philosophy of right is concerned with the state of right. To each of these disciplines Nelson added another concerned with the conditions of realizing the values studied by them: philosophical pedagogics, as the theory of the education of man to the ethical good, and philosophical politics, as the theory of the realization of the state of right.

validity of ethical principles

The logically transparent construction of the entire system reveals clearly that the principles behind all further developments are strictly valid in all cases but can be applied only through full consideration of the concrete circumstances in each individual case; since they are objectively valid, they are not subject to arbitrary decisions and are valid even in cases where human insight and will fail to understand them; but they are justified only by reference to reason, which makes possible for each individual the autonomic recognition of these standards and the critical examination of their applications. Thus, the demands of equality for all before the law and of equality of rights are compatible with the demand to differentiate according to given circumstances; and the demands of force against injustice remain linked to those of freedom of criticism and of public justification for the legal necessity of certain coercive measures. Such coercive measures are particularly necessary when the freedom of man to form himself rationally within the framework of his own life is threatened; this freedom can be threatened because man's true need for it is at first obscure and can therefore be mistaken and suppressed.

Nature and chance

One conclusion appears again and again, determining the structure of the whole system. In each case it is a question of fighting with chance, to which the realization of the good is subject in nature. What happens in nature is, according to the laws of nature, dependent on the given circumstances and on the forces working through them, which are indifferent to ethical values: Under the laws of nature it is a matter of chance whether what should happen is in fact what happens or whether ethical demands are ignored. But what ethics demands should not be subject to chance but assured by the human will. Following this line of thought, Nelson derived the law of character in ethics, which demands from man the establishment of a basic willingness to fulfill his duty, by which he makes himself independent of given concrete circumstances; his inclinations and the influences on his will may or may not be in agreement with the commands of duty.

In the philosophy of right Nelson correspondingly finds certain postulates. These determine the forms of reciprocal action in society which alone assure just relations between individuals; among them are public justice, prosecutability, the law of contract, and the law of property. The transitions from ethics to pedagogy and from philosophy of right to politics are made in the same spirit. Education, among the many influences on man, should strengthen or create those elements that develop his capacity for good and oppose those that could weaken this capacity. Politics is concerned with the realization and securing of the state of right determined by the postulates of philosophy of right. This problem leads to the postulation of a state seeking the rule of law and having the power to maintain itself against forces in society opposing the rule of law. A sufficiently powerful federation of states is necessary to regulate the legal relationships between states.

The same conclusion is reached in the last section of Nelson's System der philosophischen Rechtslehre und Politik. Here again, in a state of nature it is a matter of chance to what degree states realize the rule of law or violate its demands, unless men having insight into justice and moral will work to transform the existing state into a just state. These men must interfere in the struggle between social groups and parties and must themselves band together into a party. In this case, therefore, the ideal of a just state leads to that of a party working to achieve it.

freedom and necessity

The conflict between natural necessity and man's freedom and responsibility impelled Nelson's thinking. Ethical standards are valid for human action in nature and are therefore directly relevant to two apparently mutually exclusive forms of legality: The theoretical form, according to which everything that happens in nature (including human behavior) is determined by natural laws working through the existing powers, and the practical one, which presents the human will with duties that can either be violated and ignored or become man's purpose.

Thus on the one hand Nelson insisted that demonstrated ethical standards be maintained without compromise and rejected the skeptical assumption that man, as a limited creature of nature, was incapable of maintaining them; this assumption he considered a sacrifice of known ethical truth, a mere excuse for those who were able but not willing. On the other hand, he expected the human will to act according to the strongest motivation of the moment, without any guarantee from nature that this motivation would direct man toward what is ethically required. For this reason he rejected any speculation that in a state of nature the good would pave its own way.

Within the framework of the critique, Nelson thoroughly examined the question of how man's freedom could be reconciled with this natural law. He sought the answer in the doctrine of transcendental idealism that human knowledge is limited to the understanding of relationships in the sphere of experience but cannot achieve absolute perception of reality itself. In the consciousness of his freedom, which is indissolubly bound to the knowledge of his responsibility, man relates himself by faith to the world of that which is real in itself and superior to the limitations of nature. Nelson unified the two points of view by connecting two results of his investigations of the critique of reason: the principle of the existence of pure practical reason, which as a direct moral interest makes moral insight and moral motivation possible, and the principle of the original obscurity of this interest, according to which it does not determine judgment and will by its very existence but rather requires enlightenment and is dependent on stimulation.

education and politics

Concern with the realization of ethical requirements led Nelson beyond his philosophical work to practical undertakings, in which he gave primary emphasis to politics, particularly to political education.

Toward the end of World War I Nelson collected a circle of pupils and coworkers who were willing to undergo intensive education and discipline in preparation for the political duties imposed by ethics and philosophy of right. Together with these pupils he founded the Internationaler Jugendbund and in January 1926 developed his own political organization, the Internationaler Sozialistischer Kampf-Bund. In 1924 he opened a "country educational institution," Landerziehungsheim Walkemühle, directed by his coworker Minna Specht. Here youths and children were trained in a closely knit educational and working community for activity in the workers' movement, until the school was closed and appropriated by the National Socialists in 1933.

As a teacher and educator Nelson had a strong effect on his pupils. He led them by masterly Socratic discussions to a clarification and critical examination of their own convictions, and he required them to carry out what they had recognized as just and good in their actions with the same consistency that he demanded of himself. "Ethics is there in order to be applied."

See also Epistemology; Epistemology, History of; Ethics; Fries, Jakob Friedrich; Kant, Immanuel; Neo-Kantianism; Psychologism.


works by nelson

"Die kritische Methode und das Verhältnis der Psychologic zur Philosophic." Abhandlungen der Fries'schen Schule, n.f., 1 (1) (1904): 188.

"Jakob Friedrich Fries und seine jungsten Kritiker." Abhandlungen der Fries'schen Schule, n.f., 1 (2) (1905): 233319.

"Bermerkungen über die nicht-Euklidische Geometric und den Ursprung der mathematischen Gewissheit." Abhandlungen der Fries'schen Schule, n.f., 1 (2) (1905): 373392; 1 (3) (1906): 393430.

"Inhalt und Gegenstand, Grund und Begründung. Zur Kontroverse über die kritische Methode." Abhandlungen der Fries'schen Schule, n.f., 2 (1) (1907): 3373.

"Ist metaphysikfreie Naturwissenschaft möglich?" Abhandlungen der Fries'schen Schule, n.f., 2 (3) (1908): 241299.

"Über das sogenannte Erkenntnisproblem." Abhandlungen der Fries'schen Schule, n.f., 2 (4) (1908): 413850.

"Bemerkungen zu den Paradoxien von Russell und Burali-Forti." Abhandlungen der Fries'schen Schule, n.f., 2 (3) (1908): 301334. Written with Kurt Grelling.

"Untersuchungen über die Entwicklungsgeschichte der Kantischen Erkenntnistheorie." Abhandlungen der Fries'schen Schule, n.f., 3 (1) (1909): 3396.

"Die Unmöglichkeit der Erkenntnistheorie." Abhandlungen der Fries'schen Schule, n.f., 3 (4) (1912): 583617.

"Die Theorie des wahren Interesses und ihre rechtliche und politische Bedeutung." Abhandlungen der Fries'schen Schule, n.f., 4 (2) (1913): 395423.

"Die kritische Ethik bei Kant, Schiller und Fries." Abhandlungen der Fries'schen Schule, n.f., 4 (3) (1914): 483691.

Die Rechtswissenschaft ohne Recht. Kritische Betrachtungen über die Grundlagen des Staats- und Völkerrechts, insbesondere über die Lehre von der Souveränität. Leipzig: Veit, 1917.

Die Reformation der Gesinnung durch Erziehung zum Selbst-vertrauen. Gesammelte Aufsätze. Leipzig, 1917; 2nd enlarged ed., Leipzig, 1922.

Vorlesungen über die Grundlagen der Ethik. 3 vols. Leipzig: Veit, 19171932. Vol. II translated by Norbert Guterman as System of Ethics. New Haven, CT: Yale University Press, 1956.

Die Reformation der Philosophie durch die Kritik der Vernunft. Gesammelte Aufsätze. Leipzig, 1918.

Demokratie und Führerschaft. Leipzig, 1920.

Spuk, Einweihung in das Geheimnis der Wahrsagerkunst Oswald Spenglers. Leipzig: P. Reinhold, 1921.

"Kritische Philosophic und mathematische Axiomatik." Unterrichtsblätter für Mathematik und Naturwissenschaft, 34th year, (4 and 5) (1927): 108115 and 136142.

"Sittliche und religiöse Weltansicht." XXVI Aasaner Studenten-Konferenz, 725. Leipzig, 1922.

"Die Sokratische Methode." Abhandlungen der Fries'schen Schule, n.f., 5 (1) (1929): 2178. Translated by Thomas K. Brown in Socratic Method and Critical Philosophy. New Haven, CT: Yale University Press, 1949. Selected essays.

Fortschritte und Rückschritte der Philosophie; von Hume und Kant bis Hegel und Fries. Frankfurt: Öffentliches Leben, 1962.

works on nelson

Specht, Minna, and Willi Eichler, eds. Leonard Nelson zum Gedächtnis. Frankfurt, 1953. Contains essays.

Grete Henry-Hermann (1967)

Translated by Tessa Byck

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