The Enlightenment

2017

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TABLE OF CONTENTS

THE AGE OF THE ENLIGHTENMENT

LOCKE'S INNER AND OUTER WORLD

BERKELEY'S IDEALISM

HUME'S SCEPTICISM

THE MATERIALISTIC MOVEMENT IN ENGLAND AND FRANCE

ROUSSEAU'S PHILOSOPHY OF FEELING

THE PHILOSOPHY OF LEIBNIZ

THE CONFLICT OF TYPICAL PHILOSOPHICAL TENDENCIES IN GERMANY

THE CRITICAL PHILOSOPHY OF KANT

THE PRACTICAL INFLUENCES OF THE ENLIGHTENMENT.

THE AGE OF THE ENLIGHTENMENT

The significant movement of thought known as the Enlightenment, or Aufklärung, falls in the main within the period of the eighteenth century. It is seldom, however, that the turn of a century happens to coincide exactly with the beginning or the end of a great epoch, either political, religious or philosophical. The period in philosophy which is referred to in a general way as the eighteenth century begins virtually in the year 1690 with the publication of Locke famous Essay Concerning Human Understanding, and is brought to its close in the year 1781 with the appearance of Kant Critique of Pure Reason. They are the natural boundaries of this philosophical century.

It was an age characterised by a restless spirit of inquiry -- a century of challenge. A new life was awake and stirred in the minds of men. Traditions which had been long venerated became the objects of searching investigation and criticism. The authority of the church, of the state and of the school was no longer regarded as the court of last appeal. The old beliefs which failed to justify themselves at the bar of reason were discarded. The foundations of time-honoured systems seemed shifting and uncertain. There was an insistent demand for the free play of the individual judgment. There was, also, a constant reference to the light of reason, the inner illumination shining bright and clear in contrast to the shadows of mysticism, or to the false and flickering light of dogmatism. Hence the name of the age of illumination, or enlightenment, -- the name, also, of the age of reason.

In this period there was more particularly a spirit of protest against metaphysical speculation, that is, against all attempts to explain the phenomena of human existence in any manner which transcends the ordinary processes of reason, and consequently possesses no firm foundation of reality. And reality, in turn, was conceived as that which is akin to nature and to the general course of natural phenomena as perceived through the channels of the various senses. There was an attempt to reduce the problems of thought to the basis of extreme simplicity, and to make a common-sense view of things everywhere prevail.

The spirit of the age might find characteristic expression in some such words as these: Let us not concern ourselves with idle speculation in reference to things which the mind of man can never compass and understand. Why busy ourselves concerning the deeper significance and purpose of nature which our thought is utterly incapable of penetrating? While we may observe and classify the phenomena of nature, and formulate the laws of their behaviour, we can never hope to comprehend their inner meaning, forever veiled and obscure. Nature, which seems so near -- of which, indeed, we ourselves are a part --nevertheless lies far beyond our ken. And the being and nature of God, who must be regarded as dwelling in a sphere far out and beyond the outermost bounds of nature, must remain still more incomprehensible. If we cannot understand the inscrutable mysteries' of the world which we have seen, much less the mystery of God whom we have not seen. From the contemplation, therefore, of the world and of God, we must turn our eyes to the more rewarding study of the inner self. Let every man examine the phenomena of life as they unfold themselves within this inner world of his own consciousness. Here at least is the light in which he can see light. To every one who thus mines the treasures of his own nature there must come the quiet satisfaction of being able to insist, I know myself. Such is the spirit of this age. It is reflected in Pope's line,

The proper study of mankind is man.

In this search after knowledge, while inquiry was introspective, it was not by any means reflective. It lacked penetration, and while moving freely and thoroughly in a careful surface investigation, it was never able to fathom and explore the lower depths of thought.

It was a restricted area of inquiry, therefore, which the philosophy of the Enlightenment set for itself. If in this region, it was urged, there can be found no evidence for the existence of God, then faith must not hold what reason cannot prove; if there are no immutable principles of morality clearly attested, then man must be content with a working ethic of prudence and expediency; if there are no intimations of immortality, one can at least live in the fulness of the present; if the foundations of the state are shaken, then let the state itself fall with them; but in spite of what may be lost or of what may be saved, let no one's convictions transcend the actual and indisputable facts upon which they are observed to rest. Let man once for all penetrate the mist and veil of words, and get at the truth of things. If there is no appeal to the god of things as they are, there is, at least, the appeal direct to things as they are themselves.

With all of its obvious limitations and defects, this method of inquiry was nevertheless frank, openminded and ingenuous. The right of individual opinion was respected; a spirit of tolerance prevailed; and philosophy was afforded a free forum.

The key-note of the age was set by John Locke scholar of Christ Church, Oxford, trained in the diplomatic service, widely travelled, secretary of the first Earl of Shaftesbury, a profound student of the theory of government, champion of toleration, a man of affairs, and withal a philosopher, whose habit of mind fitted him in an eminent degree to deal with speculative problems from a practical point of view. In his Essay Concerning Human Understanding, Locke insists that all knowledge comes to us from two sources only -- from sensation and reflection. Therefore we ought scrupulously to eliminate from our philosophy everything which it is not possible to trace to this elemental origin. Aught else of speculation, of sentiment or of opinion rests upon a basis of fancy and not of fact. All inquiry, consequently, must be limited to the problems which arise in this field. Beyond these lies not only the undiscovered country, but the undiscoverable as well.

The world of knowledge from this point of view shows a variety of manifold forms, but is of one and the same substance throughout, namely, that which is constantly supplied by the ceaseless activity of the senses. Thus we find the problem of knowledge reduced to its lowest terms. By restricting the area of knowledge, the area of difficulty is likewise diminished; for many perplexing problems are thus eliminated, and a common-sense method of interpreting actually observed facts of experience commends itself as involving only clear ideas which all mankind can understand and appreciate. It was, indeed, a characteristic feature of this age, the demand that all ideas should be clear and self-illuminating. It was a part of the heritage which had come to that generation from Descartes, who had emphatically insisted that clear and distinct ideas are to be regarded as the sole test of truth. Locke placed before his own mind the same standard, and sought to realise it by a simplification of the sources of knowledge. It is here that the development of thought in the age of the Enlightenment had its beginning.

The history of this development illustrates certain fundamental principles concerning the progress of thought which are not only of interest in themselves, but will serve also to stimulate the critical insight and appreciation of any one who undertakes the serious study of this period of philosophy. We find in the eighteenth century a great movement of thought, which furnishes us a basis for an historical study of the theory of knowledge. But this is not all. It may be regarded also as the type of great thought movements in general. It has in this respect peculiarly a representative value; for if we interpret aright the controlling forces which underlie this development, and the various phases of their manifestation, there will be disclosed, in rough outline at least, the programme which every progressive movement of thought tends to follow. There are three stages of such a development. The first is that in which some significant idea finds expression, and, because not yet fully developed, it is necessarily partial, one-sided or extreme. The second stage is that of controversy. The idea must be subjected to a running fire of criticism. Whatever it may conceal as contradictory, incoherent or absurd, will thus be brought to light. The third stage is always a period of reconstruction, wherein contradictions are resolved, limitations are removed, and whatever may have been inadequate is completed by supplying the complementary elements which were wanting in the original doctrine or theory. This Hegelian procedure is illustrated in the progress of philosophical thought which the eighteenth century produced. And such a method of thought development is by no means a fanciful conceit of Hegel's. It is a process which is familiar to every one who, in his own thinking, has become conscious of the expanding and transforming stages through which his various opinions have passed, from the initial assertion, through the testing of criticism and controversy, until the final reconstruction and restatement of the original belief is reached.

At the beginning of such a development as that which the eighteenth century exhibits, the content of philosophical thought is reduced to a minimum. Its simplicity, however, is that of a germ possessing in a high degree the potential of an exceedingly complex growth. Any idea which starts a great movement of thought must be subjected to the practical test of its power to adapt itself to all possible varieties of mental environment. It must be received into many and various types of minds; it must adjust itself to many different temperaments, and be regarded from many points of view. It is only in this manner that its full significance can be revealed, and its true worth adequately appreciated. In this period of trying out, whatever is potential in the initial idea will be rendered actual; its logical implications will be made explicit, and their necessary consequences set forth in a rigorous and complete manner; whatever is partial will be revealed, and all latent error will be eliminated.

This is exactly what occurred in reference to Locke's fundamental contention that we know only that which comes through the avenues of the senses, and what may follow from reflection upon the material which is thus furnished. An exceedingly simple statement of the sources of knowledge. But there is no statement, however simple, which is not beset with difficulties and which may not become the subject of radical differences of opinion, and possibly of heated controversy. This simple statement of the Lockian theory of knowledge experienced two diametrically opposite phases of development, which in itself indicates its indefiniteness and incompleteness. One of these phases was essentially idealistic and the other materialistic, and each in turn grounded in the original premisses of Locke concerning the sources of knowledge.

The idealistic interpretation is represented by Bishop Berkeley. Starting from Locke's stand-point that the elemental springs of knowledge are to be traced to the sensations, Berkeley insists that inasmuch as every sensation is an experience occurring in the individual consciousness, it must be composed, therefore, at the last analysis, of that which is mental and not physical. Whatever appears in consciousness must partake of the character of the very element in which it appears. As to the physical object of sensation which is supposed to be outside of us and is regarded crudely as its cause, we know absolutely nothing. We know only the passing phenomena of consciousness whose parts are fashioned of mental elements or thought entities. To say, as Locke does, that we know only sensations originally, means, therefore, according to Berkeley's interpretation, that we know merely the objects of knowledge as they appear to us in consciousness, wrought of the elements of the mind only. Ideas, therefore, are the stuff out of which our experience is formed. While Locke had said that there was some external object corresponding to every perception, although its true nature could never be known to the observing mind, Berkeley insists that there is no external object to know other than the idea in the mind. Our ideas which come to us through sense perception do not represent a world lying beyond them; they are that world itself.

At the same time and, strangely enough, under the same influence, there developed a sensationalistic philosophy, which in its extreme form drifted inevitably into materialism. It flourished not only on British soil, but survived its transplanting into France, and with the changed environment gained in vigour and extent. In England this phase of the movement is represented by Hartley, Priestley, Erasmus Darwin and others; in France by that brilliant coterie of writers who gave to the world the French Encyclopædia and the revolutionary philosophy. Of this group the most pronounced in the creed of materialism were Diderot, Helvetius and Holbach.

Here surely is an anomaly. How can the same premisses yield so widely different conclusions? How can Locke's empirical beginnings develop on the one hand into Berkeley's idealism, and on the other into Holbach's materialistic and atheistic Le Sysètme de la nature? The situation, however, is not an impossible one. Upon a closer consideration, it will be seen to be both logical and natural. For we may lay it down as a general principle characteristic of every great movement of thought that, starting from a statement which is merely a partial expression of the complete truth, it must necessarily give rise to opposed results according to radical differences in the point of view and the method of interpretation. Moreover, every movement of thought must find its beginnings in some partial and indefinite expression of truth; for if it should start with a complete statement of truth, it would then be absurd to expect any possible development of it.

This, therefore, may be regarded as the first characteristic of every significant movement of thought, an initial doctrine, regarded from a single and circumscribed point of view, developing diametrically opposed conclusions. The simplicity of the original statement thus at once breaks up in the process of interpretation and elaboration into a complexity of contradictory opinions, and these contradictions clearly prove the original incompleteness.

The inadequacy of the beginnings of thought may also be illustrated more directly and particularly by. showing that the conclusions which logically follow from them are unsatisfactory as a final explanation, and that the seemingly firm foundations upon which they rest are shifting and uncertain. In reference to the philosophical position of Locke, we find the task of exposing its fundamental weakness falling to the lot of David Hume. The philosophy of Hume is a natural reaction from the extreme position of Berkeley, and at the same time its logical outcome. Because of the unsatisfactory results which Hume reaches in the logical unfolding of Locke's theory of knowledge, his attitude becomes one of radical scepticism. If Berkeley's position is tenable that Locke's doctrine leaves us only ideas as the material of our knowledge, then, Hume insists, we may, it is true, construct these elemental ideas into a world in which we can live and move and have our being; but we have no assurance whatsoever that the component elements are held together by any bonds of necessary connection, or that they possess any inherent substantiality. We think that there are real substances, individually separate and distinct, and we think there is some underlying relation of cause and effect which is the cohesive tie uniting them all into a system of interdependent parts. But such a way of looking at things is only a convenient mental habit which we take for granted as a matter of course, because we have never paused seriously to question it. We must remember that our thinking it true does not make it true, and that the most obvious assumption which the mind may entertain does not of itself guarantee its trustworthiness. Berkeley was correct in denying the existence of matter, Hume would say, but he should have gone further and have denied also the reality of ideas themselves as regards their substantial essence, and their necessary connection in any system of knowledge.

This negative criticism, which in itself marks no real progress of thought, is nevertheless an exceedingly important factor in any such progress. It shows the inadequacy of half truths, and sweeps the board of all inconsistencies and confusions of thought. If nothing remains, that very fact of itself is of advantage in inciting to renewed effort along lines which will swing clear of initial misconceptions, unwarrantable assumptions and partial premises. As Descartes has very wisely said: Those who travel very slowly may yet make far greater progress, provided they keep always to the straight road, than those who, however well they run, forsake it.

Thus, if an initial idea leads through the various phases of its logical unfolding to an untenable position, then by this process of a reductio ad absurdum, the original idea itself must be challenged at its source. This is Hume's peculiar contribution -- that of enlightening the thought of the eighteenth century as to the inadequacy of Locke's foundations of knowledge as interpreted by Berkeley. Inasmuch, therefore, as Locke's position, that we know only sensations as the beginning of all knowledge, seems to lead on one hand to an extreme idealism, and on the other to extreme materialism, or else to a point of view of radical scepticism, we are naturally forced to the conclusion that Locke must have overlooked an essential and significant factor in his account of the sources of knowledge. Is there any trace of such a factor in the midst of the eighteenth century philosophy? There undoubtedly is. For when the influence of Locke Essay began to be felt in Germany, and his empirical philosophy had gained a hearing and a following as well, there came into conflict with it an opposite stream of tendency in philosophical thinking which may be traced through Leibniz to Spinoza and Descartes, and which in the eighteenth century was represented most conspicuously in the philosophy of Wolff, namely, that of rationalism.

The point of view of rationalism has regard particularly to the nature of reason itself. It insists that there are certain clear and distinct ideas native to the very character of thought which serve as a body of primary truths from which it is possible to develop by logical procedure an entire system of philosophical dogma. Moreover, such a system is supposed to sketch, in broad outline at least, the general field of knowledge. During the latter half of the eighteenth century this method of philosophical thought had developed an extreme philosophical position, and under the dominance of Wolff's mechanical and artificial habit of mind had become a system of dry-as-dust scholastic formulae. It was a body of knowledge, but lacked the breath of life.

Through these opposed tendencies of empiricism and rationalism, each forced by the momentum of thought to an extreme expression, the way was prepared for a complete reconstruction of philosophical doctrine which was achieved by the genius of Immanuel Kant. His masterly insight discovered in the empiricism of Locke the germs of rationalism, and in the rationalism of Liebniz the potential elements of empiricism.

It was Hume whose scepticism first impressed Kant with the unsatisfactory results of the traditional methods of philosophical thinking, and opened before him the new way. The office of a sceptic in philosophy is most perfectly illustrated in the influence which Hume exerted upon the mind of Kant, leading him in the first place to a destructive analysis of the philosophical dogma in which he had been schooled, and then beyond that to the more serious task of constructive interpretation. Scepticism as an essential moment in the philosophy of the Enlightenment expresses not a final goal, but merely a transition stage in the progress of reflective thought.

Kant's problem was that of marking the precise limits of empiricism and rationalism, and of demonstrating thereby their complementary rather than contradictory nature. He examines the extreme positions of empiricism and rationalism, and then proceeds to build into a single system whatever elements of truth these seemingly opposed doctrines contain.

This marks the third stage of the movement of thought, the construction of a fully rounded body of truth by filling out the half truth which marks its initial expression. The antithesis of a rationalistic and an empirical philosophy was reconciled in the Kantian synthesis, according to which the material of our ideas is furnished by the senses in its crude state, but the form which this material is constrained to take in consciousness is the labour of the reason. As Kant succinctly puts it, ideas without any perception by the senses are empty, but mere sensations without ideas are blind. Upon the raw material of sensation the mind brings to bear its organising and constructing activity, ordering all things according to the compulsion of its own nature. We are in error when we say that we receive impressions through the avenues of the senses. The mind is never passive, but actively creative in every sense perception, however simple and elemental it may appear. A merely receptive experience, therefore, may not be regarded as the sole beginning of knowledge, for the experience is nothing without the thought which renders the elements of experience intelligible. Mere sensations in themselves, or any combination which may be made of them, can never produce a body of knowledge any more than crude ore can fashion itself into a curiously chased jewel. The simple sensation as the primal element of knowledge is a philosophical fiction. The simplest possible sensation at its first appearance in consciousness is already indefinitely complex, shot through and through with the threads of necessary connections and relations determined by the very nature of the thought processes in whose medium it necessarily comes into being. This, accordingly, is Kant's peculiar office, that of uniting these two opposed points of view, the empirical and the rational, upon a higher plane, wherein the elements of truth in each may be harmoniously conserved and ordered according to their mutual relations and functions.

Moreover, Kant also insisted most emphatically that such a position as that of Locke's was too circumscribed, and therefore could not represent in any adequate manner the full wealth of our conscious life. The tendency of the following of Locke in France, and in Germany as well, had been to emphasise unduly the function of reason as they conceived it. It is true, Kant confesses, that by the pure reason we can come to know only the phenomena of experience, the world of appearance; and no activity of the speculative reason is able to transcend this surface show of things, and reveal the substantial nature and significance of things as they are in themselves, the world of reality. But it must not be overlooked that there is also the practical reason, that quality of reason which feels and wills and acts, yet, nevertheless, maintains its essential character as reason. In this view Kant was influenced to no small extent by the insistence of Rousseau, who protested most vehemently against the methods of the age of reason, and insisted that man must be regarded