- Special Introduction
- I.: Descartes—his Life and Writings .
- II.: Philosophy In the Fifteenth and Sixteenth Centuries Preceding Descartes .
- III.: The Cogito Ergo Sum — Its Nature and Meaning .
- IV.: Cogito Ergo Sum — Objections to the Principle.
- V.: The Guarantee of the Principle .
- VI.: The Criterion of Truth .
- VII.: The Ego and the Material World .
- VIII.: Innate Ideas.
- IX.: Malebranche (1638-1715) †
- X.: Spinoza (1632-1677) — Relations to Descartes .
- XI.: Development of Cartesianism In the Line of Spinoza—omnis Determinatio Est Negatio .
- XII.: Hegelian Criticism — the Ego and the Infinite .
- Discourse On Method
- Part I.
- Part II.
- Part III.
- Part IV.
- Part V.
- Part VI.
- The Meditations
- Preface to the Reader.
- Synopsis of the Six Following Meditations.
- Meditations On the First Philosophy In Which the Existence of God, and the Real Distinction of Mind and Body, Are Demonstrated.
- Meditation I.: Of the Things On Which We May Doubt .
- Meditation II.: Of the Nature of the Human Mind ; and That It Is More Easily Known Than the Body .
- Meditation III.: Of God: That He Exists.
- Meditation IV.: Of Truth and Error .
- Meditation V.: Of the Essence of Material Things ; and , Again , of God; That He Exists .
- Meditation VI.: Of the Existence of Material Things , and of the Real Distinction Between the Mind and Body of Man .
- The Principles of Philosophy.
- To the Most Serene Princess , Elisabeth, Eldest Daughter of Frederick, King of Bohemia, Count Palatine , and Elector of the Sacred Roman Empire .
- The Principles of Philosophy.
- Part I.: Of the Principles of Human Knowledge .
- Part II.: Of the Principles of Material Things .
- Part III.: Of the Visible World .
- Part IV.: Of the Earth .
- Appendix: Reasons Which Establish the Existence of God, and the Distinction Between the Mind and Body of Man, Disposed In Geometrical Order.
Centuries Preceding Descartes.
The first step in the continuous progress to the principle of free inquiry, whose influence we now feel, was taken in the fifteenth century. This epoch presented for the first time in modern history the curious spectacle of the supreme authority in matters of thought and faith turned against itself. The principle of authority had been consecrated by scholasticism. During its continuance, intellectual activity was confined to methodizing and demonstrating the truths or dogmas furnished to the mind by the Church. No mediaeval philosopher thought of questioning the truth of a religious dogma, even when he found it philosophically false or indemonstrable. The highest court of philosophical appeal in scholasticism was Aristotle; and the received interpretations of “the philosopher” had become identified with the dogmas sanctioned by the Church, and therefore with its credit and authority. But events occurred in the middle of the fifteenth century which tended to disparage the Aristotle of the Schools. Hitherto the writings of Aristotle had been known in Europe only through Latin translations, often badly and incompetently made from the Arabic and Hebrew. The emigration of learned Greeks from the empire of the East under the pressure of Turkish invasion, and finally the fall of Constantinople in 1453, led to the distribution of the originals of Aristotle over Italy, and the spread of the Greek language in Western Europe. With the knowledge thus acquired at first hand, Pomponatius (1462-1524 or 1526) disputed the dogmas of the Aristotle of the Schools and the Church. Henceforward the Aristotelians were divided into two Schools,— the Averroists or traditional interpreters, and the followers of “the Commentator,” Alexander of Aphrodisias. Pomponatius was the head of the latter party. While still recognizing his authority as the highest, Pomponatius denied that the Aristotle which the Church accepted was the true one. The real Aristotle, according to his view, denied a divine providence, the immortality of the soul, and a beginning of the world; or, as he sometimes put it, Aristotle did not give adequate proof on those points. The philosopher and the Church were therefore in contradiction. This led to ardent discussion,— the opening of men's minds to the deepest questions,— the beginning, in a word, of free thought. And there was also the practical result, that the fifteenth-century philosopher denied what he as a Churchman professed to believe, or rather did not dare to disavow. It was obvious that the course of thinking could not rest here. It must pass beyond this, urged alike by the demands of reason and the interests of conscience.
But the inner spirit of scholasticism had pretty well worked itself out. It was a body of thought remarkable for its order and symmetry, well knit and squared, solid and massive, like a mediaeval fortress. But it was inadequate as a representation and expression of the free life that was working in the literature, and even in the outside nascent philosophy, of the time. It was formed for conservation and defense, not for progress. New weapons were being forged which must inevitably prevail against it, just as the discovery of gunpowder had been quietly superseding the heavy panoply of the knight. Several thoughtful men were already dissatisfied alike with the Aristotle of the schoolmen and the manuscripts. Opportunely enough, the circumstances which led to the discovery of the original Aristotle led also to the revelation of the original Plato. Some thinkers fell back on the earlier philsopher, stimulated to enthusiasm by the elevation of his transcendent dialectic. Notably among these were Pletho (born about 1390, and died about 1490); his pupil, Bessarion (1395 or 1389–1472); Giovanni Pico della Mirandola (the nephew of Francisco, born 1463, died 1494); Ficino, tutor to Lorenzo de Medici (1433–1499); Patrizi (1529–1597). Influenced a good deal by the spirit of mediaeval mysticism, these thinkers for the most part clothed their Plato in the garb of Plotinus and the Neo-Platonists. Others were led to the still earlier Greek philosophers. The newly-awakened spirit of experience in Telesio (1508–1588) and in Berigard (1578–1667) found fitting nourishment in the Ionian physicists; and, later in the same line, Gassendi (1592–1655) revived Epicurus. All this implied the individual right of selecting the authority entitled to credence, and was a protest against scholasticism, and a step toward free inquiry.
The men of letters also helped to swell the tide rising strong against scholasticism. The abstract and often barbarous language of the schools appeared tasteless and repulsive alongside the rhythmic diction of Cicero, and the polished antitheses of Seneca. The spirit of imagination and literary grace had been repressed to the utmost in the schools. It now asserted itself with the intensity peculiar to a strong reaction. And in the knowledge and study of the forms of the classical languages, the mind is far beyond the sphere of mere deduction. It is but one remove from the activity of thought itself.
Mysticism, always operative in the middle ages, and indeed involved in the Neo-Platonism already spoken of, came to its height in the period of the Renaissance — especially under Paracelsus, (1493–1541) and Cardan (1501–1576) — and then under Boehm (1575–1624) and the Van Helmonts (father, 1577–1644, and son, 1618–1699). The principle of transcendent vision by intuition was in direct antagonism with the reasoned authority of scholasticism. Boehm's philosophy on its speculative side was an absolutism which anticipated Schelling, and Hegel himself. The self-diremption of consciousness is Boehm's favorite and fundamental point. The superstition which lay at the heart of the mysticism of the time, and which showed itself practically in alchemy, led men by the way of experiment to natural science, especially chemistry.
At length in the sixteenth century, and, as if to show the extreme force of reaction, in Italy itself before the throne of the Pope and the power of the Inquisition, there arose in succession Bruno (b. about 1550, d. 1600), Vanini (1581 or 85–1619), and Campanella (1568–1639) — all deeply inspired by the spirit of revolt against authority, and a freedom of thought that reached even a fantastic license. Bruno in the spirit of the Eleatics and Plotinus, proclaimed the absolute unity of all things in the indeterminable substance, which is God; Vanini carried empiricism to atheism and materialism; and Campanella united the extremes of high churchman and sensationalist, mystical metaphysician and astrologist.
The thoughts of this period, from the fifteenth to well on in the sixteenth century, have been described as “the upturnings of a volcano.” The time was indeed the volcanic epoch in European thought. The principal figures we can discern in it seem to move amid smoke and turmoil, and to pass away in flame. The tragic fate of Bruno in the fire at Rome, and that of Vanini in the fire at Toulouse — both done to death at the instance of the vulgar unintelligence of the Catholicism of the time — form two of the darkest and coarsest crimes ever perpetrated in the name of a Church. The Church, which claims to represent the truth of God, dare not touch with a violent hand speculative opinion. It is then false to itself.
In France, and in the university of Paris, the stronghold of Peripateticism, Ramus (1515–1572) attacked Aristotle in the most violent manner. In Ramus was concentred the spirit of philosophical and literary antagonism to the schoolmen. It was wholly unmodified by judgment or discrimination, and it did not proceed on a thorough or even adequate acquaintance with the object of its assault. Ramus is remarkable chiefly for the extreme freedom which he asserted in oratorically denouncing what he considered to be the principles of Aristotle; but he made no real advance either in the principles of logical method which he professed, or in philosophy itself. At the same time, the rude intensity and the passionate earnestness of his life were not unworthily sealed by his bloody death on the Eve of St. Bartholomew. The death of Ramus, though attributed directly to personal enmity, was really a blow struck alike at Protestantism and the freedom of modern thought.
Bruno, Vanini, Campanella, and Ramus foreshadowed Descartes and the modern spirit, only in the emphatic assertion of the freedom, individuality, and supremacy of thought. What in thought is firm, assured, and universal, they have not pointed out. They were actuated mainly by an implicit sense of inadequacy in the current principles and doctrines of the time. It was not given to any of them to find a new and strong foundation whereon to build with clear, consistent, and reasonable evidence. Campanella said of himself not inaptly: “ I am but the bell (campanella) which sounds the hour of a new dawn.”
Alongside of those more purely speculative tendencies, Copernicus, Kepler, Galileo, and Bacon represented the new spirit and theory of observation applied to nature. The formalism of the Schools had abstracted almost entirely from the natural world. It was a “dreamland of intellectualism.” And now there came an intense reaction, out of which has arisen modern science. Bacon had given to the world the Novum Organum in 1620, seventeen years before the Method of Descartes, but his precept was as yet only slightly felt, and he had but little in common with Descartes, except an appeal to reality on a different side from that of the Continental philosopher. Descartes had not seen the Organum previously to his thinking out the Method. He makes but three or four references to Bacon in all his writings.
If to these influences we add the spirit of religious reformation, the debates regarding the relative authority of the Scriptures and the Church, and mainly as a consequence of the chaos and conflict of thought in the age, the course of philosophical scepticism initiated by Cornelius Agrippa (1486–1535), and made fashionable especially by Montaigne (1533–1592), and continued by Charron (1541–1603), with its self-satisfied worldliness and its low and conventional ethic, we shall understand the age in which the youth of Descartes was passed, and the influences under which he was led to speculation. We shall be able especially to see how he, a man of penetrating and comprehensive intelligence, yet with a strong conservative instinct for what was elevating in morals and theology, was led to seek for an ultimate ground of certainty, if that were possible, not in tradition or dogma of philosopher or churchman, but in what commended itself to him as self-verifying and therefore ultimate in knowledge—in other words, a limit to doubt, a criterion of certainty, and a point of departure for a constructive philosophy.