Lecture 7. The Philosophy of the New Age and Enlightenment.
The Age of Enlightenment (or simply the Enlightenment or Age of Reason) was a cultural movement of intellectuals in the 17th and 18th centuries, first in
Originating about 1650 to 1700, it was sparked by philosophers Baruch Spinoza (1632–1677), John Locke (1632–1704), Pierre Bayle (1647–1706), physicist Isaac Newton (1643–1727), and philosopher Voltaire (1694–1778). Ruling princes often endorsed and fostered figures and even attempted to apply their ideas of government in what was known as Enlightened Despotism. The Enlightenment flourished until about 1790–1800, after which the emphasis on reason gave way to Romanticism’s emphasis on emotion and a Counter-Enlightenment gained force.
In France, Enlightenment was based in the salons and culminated in the great Encyclopédie (1751–72) edited by Denis Diderot (1713–1784) with contributions by hundreds of leading philosophes (intellectuals) such as Voltaire (1694–1778), Rousseau (1712–1778) and Montesquieu (1689–1755). Some 25,000 copies of the 35 volume set were sold, half of them outside
The medieval view of the world as a hierarchical order of beings created and governed by God was supplanted by the mechanistic picture of the world as a vast machine, the parts of which move in accordance with strict physical laws, without purpose or will. In this view of the universe, known as Mechanism, science took precedence over spirituality, and the surrounding physical world that we experience and observe received as much, if not more, attention than the world to come. The aim of human life was no longer conceived as preparation for salvation in the next world, but rather as the satisfaction of people’s natural desires. Political institutions and ethical principles ceased to be regarded as reflections of divine command and came to be seen as practical devices created by humans.
The human mind itself seemed an inexhaustible reality, on a par with the physical reality of matter. Modern philosophers had the task of defining more clearly the essence of mind and of matter, and of reasoning about the relation between the two. Individuals ought to see for themselves, they believed, and study the “book of Nature,” and in every case search for the truth with their own reason.
Since the 15th century modern philosophy has been marked by a continuing interaction between systems of thought based on a mechanistic, materialistic interpretation of the universe and those founded on a belief in human thought as the only ultimate reality. This interaction has reflected the increasing effect of scientific discovery and political change on philosophical speculation.
Mechanism and Materialism
In the new philosophical climate, experience and reason became the sole standards of truth. The first great spokesman for the new philosophy was the English philosopher and statesman Francis Bacon, who denounced reliance on authority and verbal argument and criticized Aristotelian logic as useless for the discovery of new laws. Bacon called for a new scientific method based on reasoned generalization from careful observation and experiment. He was the first to formulate rules for this new method of drawing conclusions, now known as inductive inference.
Galileo
Galileo Galilei (Italian pronunciation: [ɡaliˈlɛːo ɡaliˈlɛi]; 15 February 1564 – 8 January 1642),[was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism. Galileo has been called the “father of modern observational astronomy”, the “father of modern physics”, the “father of science”, and “the Father of Modern Science”.
quick facts
Galileo
Italian physicist and astronomer
Birth
February 15, 1564
Death
January 8, 1642
Place of Birth
Known for
Making a number of important astronomical discoveries, including the four moons of Jupiter, sunspots, and the myriad of stars that compose the Milky Way
Proposing that falling bodies would all fall at the same rate, regardless of mass, if there were no air resistance
Milestones
1589 Taught mathematics at the
1592 Taught mathematics at the
1609 Reinvented the telescope based on hearsay of such a device’s existence in
1610 Studied the heavens with his telescope, and discovered mountains on the Moon, thousands of stars too faint to be seen unaided, the phases of Venus, and other important astronomical findings
1610 Published several of his astronomical findings in Sidereus Nuncius (The Starry Messenger)
1610 Accepted a position as mathematician and philosopher to the Grand Duke of Tuscany
1632 Published a defense of the Copernican heliocentric (sun-centered) universe
1633 The Roman Catholic Church forced Galileo to recant his support of the Copernican system, and placed him under lifelong house arrest.
Did You Know
Galileo died in 1642, while under house arrest imposed upon him by the Roman Catholic Church. In 1992, the Church acknowledged that its condemnation of Galileo was a mistake.
Galileo helped develop the scientific method by using experimentation to test physical theories.
Galileo constructed the first thermometer.
Galileo (1564-1642), Italian physicist and astronomer, who, with the German astronomer Johannes Kepler, initiated the scientific revolution that flowered in the work of the English physicist Sir Isaac Newton. Born Galileo Galilei, his main contributions were, in astronomy, the use of the telescope in observation and the discovery of sunspots, lunar mountains and valleys, the four largest satellites of Jupiter, and the phases of Venus. In physics, he discovered the laws of falling bodies and the motions of projectiles. In the history of culture, Galileo stands as a symbol of the battle against authority for freedom of inquiry.
Galileo was borear
At
By December 1609, Galileo had built a telescope of 20 times magnification, with which he discovered mountains and craters on the moon. He also saw that the Milky Way was composed of stars, and he discovered the four largest satellites of Jupiter. He published these findings in March
Professors of philosophy scorned Galileo’s discoveries because Aristotle had held that only perfectly spherical bodies could exist in the heavens and that nothing new could ever appear there. Galileo also disputed with professors at
Early in 1616, Copernican books were subjected to censorship by edict, and the Jesuit cardinal Robert Bellarmine instructed Galileo that he must no longer hold or defend the concept that the earth moves. Cardinal Bellarmine had previously advised him to treat this subject only hypothetically and for scientific purposes, without taking Copernican concepts as literally true or attempting to reconcile them with the Bible. Galileo remained silent on the subject for years, working on a method of determining longitudes at sea by using his predictions of the positions of Jupiter’s satellites, resuming his earlier studies of falling bodies, and setting forth his views on scientific reasoning in a book on comets, The Assayer (1623; trans. 1957).
In 1624 Galileo began a book he wished to call “Dialogue on the Tides,” in which he discussed the Ptolemaic and Copernican hypotheses in relation to the physics of tides. In 1630 the book was licensed for printing by Roman Catholic censors at
Galileo’s final book, Discourses Concerning Two New Sciences (trans. 1662-65), which was published at
Galileo’s most valuable scientific contribution was his founding of physics on precise measurements rather than on metaphysical principles and formal logic. More widely influential, however, were The Starry Messenger and the Dialogue, which opened new vistas in astronomy. Galileo’s lifelong struggle to free scientific inquiry from restriction by philosophical and theological interference stands beyond science. Since the full publication of Galileo’s trial documents in the 1870s, entire responsibility for Galileo’s condemnation has customarily been placed on the Roman Catholic church. This conceals the role of the philosophy professors who first persuaded theologians to link Galileo’s science with heresy. An investigation into the astronomer’s condemnation, calling for its reversal, was opened in 1979 by Pope John Paul II. In October
The work of Italian physicist and astronomer Galileo was of even greater importance in the development of a new worldview. Galileo brought attention to the importance of applying mathematics to the formulation of scientific laws. This he accomplished by creating the science of mechanics, which applied the principles of geometry to the motions of bodies. The success of mechanics in discovering reliable and useful laws of nature suggested to Galileo and to later scientists that all nature is designed in accordance with mechanical laws.
These great changes of the 15th and 16th centuries brought about two intellectual crises that profoundly affected Western civilization. First, the decline of Aristotelian science called into question the methods and foundations of the sciences. This decline came about for a number of reasons including the inability of Aristotelian principles to explaiew observations in astronomy. Second, new attitudes toward religion undermined religious authority and gave agnostic and atheistic ideas a chance to be heard.
Descartes
Descartes, René
I. INTRODUCTION
Descartes, René (1596-1650), French philosopher, scientist, and mathematician, sometimes called the father of modern philosophy.
Born in
It was probably during the first years of his residence in the
II. PHILOSOPHY
Descartes attempted to apply the rational inductive methods of science, and particularly of mathematics, to philosophy. Before his time, philosophy had been dominated by the method of Scholasticism, which was entirely based on comparing and contrasting the views of recognized authorities. Rejecting this method, Descartes stated, “In our search for the direct road to truth, we should busy ourselves with no object about which we cannot attain a certitude equal to that of the demonstration of arithmetic and geometry.” He therefore determined to hold nothing true until he had established grounds for believing it true. The single sure fact from which his investigations began was expressed by him in the famous words Cogito, ergo sum,”I think, therefore I am.” From this postulate that a clear consciousness of his thinking proved his own existence, he argued the existence of God. God, according to Descartes’s philosophy, created two classes of substance that make up the whole of reality. One class was thinking substances, or minds, and the other was extended substances, or bodies.
III. SCIENCE
Descartes’s philosophy, sometimes called Cartesianism, carried him into elaborate and erroneous explanations of a number of physical phenomena. These explanations, however, had value, because he substituted a system of mechanical interpretations of physical phenomena for the vague spiritual concepts of most earlier writers. Although Descartes had at first been inclined to accept the Copernican theory of the universe with its concept of a system of spinning planets revolving around the sun, he abandoned this theory when it was pronounced heretical by the Roman Catholic church. In its place he devised a theory of vortices in which space was entirely filled with matter, in various states, whirling about the sun.
In the field of physiology, Descartes held that part of the blood was a subtle fluid, which he called animal spirits. The animal spirits, he believed, came into contact with thinking substances in the brain and flowed out along the channels of the nerves to animate the muscles and other parts of the body.
Descartes’s study of optics led him to the independent discovery of the fundamental law of reflection: that the angle of incidence is equal to the angle of reflection. His essay on optics was the first published statement of this law. Descartes’s treatment of light as a type of pressure in a solid medium paved the way for the undulatory theory of light.
IV. MATHEMATICS
The most notable contribution that Descartes made to mathematics was the systematization of analytic geometry (see Geometry: Analytic Geometry). He was the first mathematician to attempt to classify curves according to the types of equations that produce them. He also made contributions to the theory of equations. Descartes was the first to use the last letters of the alphabet to designate unknown quantities and the first letters to designate known ones. He also invented the method of indices (as in x2) to express the powers of numbers. In addition, he formulated the rule, which is known as Descartes’s rule of signs, for finding the number of positive and negative roots for any algebraic equation.
During the 17th century French mathematician, physicist, and philosopher René Descartes attempted to resolve both crises. He followed Bacon and Galileo in criticizing existing methods and beliefs, but whereas Bacon had argued for an inductive method based on observed facts, Descartes made mathematics the model for all science. Descartes championed the truth contained in the “clear and distinct ideas” of reason itself. The advance toward knowledge was from one such truth to another, as in mathematical reasoning. Descartes believed that by following his rationalist method, one could establish first principles (fundamental underlying truths) for all knowledge—about man, the world, and even God.
Descartes resolved to reconstruct all human knowledge on an absolutely certain foundation by refusing to accept any belief, even the belief in his own existence, until he could prove it to be necessarily true. In his so-called dream argument, he argued that our inability to prove with certainty when we are awake and when we are dreaming makes most of our knowledge uncertain. Ultimately he concluded that the first thing of whose existence one can be certain is oneself as a thinking being. This conclusion forms the basis of his well-known argument, “Cogito, ergo sum” (“I think, therefore I am”). He also argued that, in pure thought, one has a clear conception of God and can demonstrate that God exists. Descartes argued that secure knowledge of the reality of God allowed him to have his earlier doubts about knowledge and science.
Despite his mechanistic outlook, Descartes accepted the traditional religious doctrine of the immortality of the soul and maintained that mind and body are two distinct substances, thus exempting mind from the mechanistic laws of nature and providing for freedom of the will. His fundamental separation of mind and body, known as dualism, raised the problem of explaining how two such different substances as mind and body can affect each other, a problem he was unable to solve that has remained a concern of philosophy ever since. Descartes’s thought launched an era of speculation in metaphysics as philosophers made a determined effort to overcome dualism—the belief in the irreconcilable difference between mind and matter—and obtain unity. The separation of mind and matter is also known as Cartesian dualism after Descartes.
Hobbes
Hobbes, Thomas
Hobbes, Thomas (1588-1679), English philosopher and political theorist (see Political Theory), one of the first modern Western thinkers to provide a secular justification for the political state. The philosophy of Hobbes marked a departure in English philosophy from the religious emphasis of Scholasticism. His ideas represented a reaction against the decentralizing ideas of the Reformation (1517-1648), which, Hobbes contended, brought anarchy (see Anarchism). Regarded as an important early influence on the philosophical doctrine of utilitarianism, Hobbes also contributed to modern psychology and laid the foundations of modern sociology by applying mechanistic principles (see Mechanism) in an attempt to explain human motivation and social organization. See also Thematic Essay: British Political and Social Thought.
Born in Malmesbury, Hobbes was educated at Magdalen Hall,
In 1642 Hobbes finished De Cive, (On Citizenship; translated in 1651), a statement of his theory of government. From 1646 to 1648 he was mathematics tutor to the Prince of Wales, later King Charles II, who was living in exile in
In 1660, when the Commonwealth ended and his former pupil acceded to the throne, Hobbes again came into favor. In 1666, however, the House of Commons passed a bill including Leviathan among the books to be investigated on charges of atheistic tendencies (Hobbes argued for a distinction between knowledge and faith and suggested that one could not gain a knowledge of God—see Atheism; Agnosticism). The measure caused Hobbes to burn many of his papers and to delay publication of three of his works: Behemoth: The History of the Causes of Civil Wars of England; Dialogues Between a Philosopher and a Student of the Common Laws of England; and a metrical Historia Ecclesiastica. At the age of 84, Hobbes wrote an autobiography in Latin verse. Within the next three years he translated into English verse the Iliad and the Odyssey of Homer. He died at the age of
Developing his politics and ethics from a naturalistic basis of self-interest (see Naturalism; Egoism), Hobbes held that since people are fearful and predatory they must submit to the absolute supremacy of the state, in both secular and religious matters, in order to live by reason and gain lasting preservation. Within psychology, he proposed that all human actions are caused by material phenomena (see Materialism), with people motivated by what he termed appetite (movement toward an object; similar to pleasure) or aversion (movement away from an object; similar to pain).
The 17th–century English philosopher Thomas Hobbes, in his effort to attain unity, asserted that matter is the only real substance. He constructed a comprehensive system of metaphysics that provided a solution to the mind-body problem by reducing mind to the internal motions of the body. He also argued that there is no contradiction between human freedom and causal determinism—the view that every act is determined by a prior cause. Both, according to Hobbes, work in accordance with the mechanical laws that govern the universe.
In his ethical theory Hobbes derived the rules of human behavior from the law of self-preservation and justified egoistic action as the natural human tendency. In his political theory he maintained that government and social justice are artificial creations based on social contract (voluntary agreement between people and their government) and maintained by force. In his most famous work, Leviathan (1651), Hobbes justified political authority on the basis that self-interested people who existed in a terrifying “state of nature”—that is, without a ruler—would seek to protect themselves by forming a political commonwealth that had rules and regulations. He concluded that absolute monarchy is the most effective means of preserving peace.
Spinoza
Spinoza, Baruch
I. INTRODUCTION
Spinoza, Baruch or Spinoza, Benedict (1632-1677), Dutch rationalist philosopher and religious thinker, who is accounted the most thoroughgoing modern exponent of pantheism.
Born of Spanish-Portuguese Jewish parents in
II. PHILOSOPHY
Spinoza’s fullest expression is his great work Ethica Ordine Geometrico Demonstrata (1677 Ethics Demonstrated with Geometrical Order). According to this treatise the universe is identical with God, who is the uncaused “substance” of all things. The conception of substance, which Spinoza derived from the Scholastic philosophers, is not that of a material reality but rather of a metaphysical entity, the comprehensive and self-sufficient basis for all reality. Spinoza conceded the possible existence of infinite attributes of substance, but held that only two are accessible to the human mind, namely, extension, or the world of material things, and conscious thought. Thought and extension are considered to depend on and exist in an ultimate reality, God. Causation, in Spinoza’s system, may exist between individual objects (that is, between physical bodies) in the attribute extension, or between individual ideas in the attribute thought, but not between objects and ideas. To explain the apparent causal interactions between objects and ideas, Spinoza advanced a theory known as parallelism, according to which every idea has a physical counterpart and, similarly, every physical object has an ideational counterpart.
The individuality of things, whether physical objects or ideas, Spinoza explained as particular modes of substance. All particular objects are the modes of God in the attribute extension; all particular ideas are the modes of God in the attribute thought. The modes are natura naturata,”nature begotten,” or nature in the multiplicity of its manifestations; substance or God is natura naturans, “nature begetting,” or nature in its creative unity, acting as the determiner of its own modes. The modes are transitory, and their existence assumes temporal form; God is eternal, transcending all modal changes. Particular things accordingly, whether of extension or of thought, are finite and evanescent. Spinoza maintained, nevertheless, that an indestructible world does exist. This world is not to be found in the realm of existent things but in that of essence. Humanity’s intuitive knowledge of God is the source of a spiritual love of God (amor Dei intellectualis), which in turn is a part of the love in which God loves himself.
Spinoza’s conception of essences is closely related to the Scholastic conception of “reals” and to Plato’s conception of archetypal Ideas, although it differs from both in certain important respects. Spinoza conceived essences as hypostatizations (conceptual entities) of the universal aspect of all things. The fundamental difference between existences and essences in Spinoza’s cosmology is that the former have their being in time, but the latter are outside of time. Because mortality can pertain only to things subject to the law of time, the realm of essences, being timeless, must consequently be eternal. Nevertheless, the realm of essences is a realm of immanent being.
Every existence has, as previously indicated, a universal or essential character, although to realize this character the existent thing must transcend its own intrinsic form, that is, free itself from the boundaries of its own structure. The realm of essences thus has a kind of being within the realm of existences (the former being the immanent cause of the latter), although it does not share its temporal limitation. Immanent causation, according to Spinoza’s metaphysics, means self-causation, and that which is self-determined is free. From this reasoning Spinoza developed his doctrine of freedom as a good to be won only in the realm of essences. Existence in either attribute (extension or thought) is bondage, for each existent thing is determined by its own causal series; every particular object or idea is subject to other objects or ideas, and the form of its being is determined by them. Only in nontemporal, self-caused being, that is, in the universal and immanent, is complete freedom possible; only by identification with substance, or God, is immortality, and with it peace, obtained.
III. REJECTION OF THE TRADITIONAL
Spinoza rejected providence and freedom of will, and his concept of an impersonal God was hostilely received by many of his contemporaries. His position in the history of philosophy is in many respects unique. He belonged to no school and founded none. Although to some extent his work was based on that of a few of his predecessors, it is too strikingly individual to be regarded as a mere continuation, even of the thought of Descartes. In the depth and grandeur of his conception, and in his remarkable power of synthesis, Spinoza ranks with the greatest philosophical thinkers. Only a century after his death on February 21, 1677, did his thought gain recognition, and although his system gave rise to no organized following, he has had perhaps the most pervasive influence of all modern philosophers with the exception of Immanuel Kant, a German. Not only metaphysicians but poets such as Goethe (a German) and William Wordsworth and Percy Shelley (both British) have consulted the works of Spinoza for inspiration, and his thought has influenced the poetic pantheism of many modern interpretations of nature.
Whereas Hobbes tried to oppose Cartesian dualism by reducing mind to matter, the 17th-century Dutch philosopher Baruch Spinoza attempted to reduce matter to divine spiritual substance. He constructed a remarkably precise and rigorous system of philosophy that offered new solutions to the mind-body problem and to the conflict between religion and science. Like Descartes, Spinoza maintained that the entire structure of nature can be deduced from a few basic definitions and axioms, on the model of Euclidean geometry. However, Spinoza believed that Descartes’s theory of two substances created an insoluble problem of the way in which mind and body interact. He concluded that the ultimate substance is God and that God, substance, and nature are identical. Thus he supported the pantheistic view that all things are aspects or modes of God (see Pantheism).
Spinoza’s solution to the mind-body problem explained the apparent interaction of mind and body by regarding them as two forms of the same substance, which exactly parallel each other, thus seeming to affect each other but not really doing so. Spinoza’s ethics, like the ethics of Hobbes, was based on a materialistic psychology according to which individuals are motivated only by self-interest. But in contrast to Hobbes, Spinoza concluded that rational self-interest coincides with the interest of others.
Locke
John Locke was an English philosopher and physician regarded as one of the most influential of Enlightenment thinkers.
English philosopher John Locke responded to the challenge of Cartesian dualism by supporting a commonsense view that the corporeal (bodily or material) and the spiritual are simply two parts of nature that remain always present in human experience. He made no attempt to rigorously define these parts of nature or to construct a detailed system of metaphysics that attempted to explain them; Locke believed that such philosophical aims were impossible to carry out and thus pointless. Against the rationalism of Descartes and Spinoza, who believed in the ability to achieve knowledge through reasoning and logical deduction, Locke continued the empiricist tradition begun by Bacon and embraced by Hobbes. The empiricists believed that knowledge came from observation and sense perceptions rather than from reason alone.
In 1690 Locke gave empiricism a systematic framework with the publication of his Essay Concerning Human Understanding. Of particular importance was Locke’s redirection of philosophy away from the study of the physical world and toward the study of the human mind. In so doing he made epistemology, the study of the nature of knowledge, the principal concern of philosophy in the 17th and 18th centuries. In his own theory of the mind Locke attempted to reduce all ideas to simple elements of experience, but he distinguished sensation and reflection as sources of experience, sensation providing the material for knowledge of the external world, and reflection the material for knowledge of the mind.
Locke greatly influenced the skepticism of later British thinkers, such as George Berkeley and David Hume, by recognizing the vagueness of the concepts of metaphysics and by pointing out that inferences about the world outside the mind cannot be proved with certainty. His ethical and political writings had an equally great influence on subsequent thought. During the late 18th century the founders of the modern school of utilitarianism, which makes happiness for the largest possible number of people the standard of right and wrong, drew heavily on the writings of Locke. His defense of constitutional government, religious tolerance, and natural human rights influenced the development of liberal thought during the late 18th century in
John Stuart Mill was a British philosopher, political economist and civil servant. He was an influential contributor to social theory, political theory, and political economy. He has been called “the most influential English-speaking philosopher of the nineteenth century”. Mill’s conception of liberty justified the freedom of the individual in opposition to unlimited state control. He was a proponent of utilitarianism, an ethical theory developed by Jeremy Bentham. Hoping to remedy the problems found in an inductive approach to science, such as confirmation bias, he clearly set forth the premises of falsification as the key component in the scientific method. Mill was also a Member of Parliament and an important figure in liberal political philosophy.
Jeremy Bentham was a British philosopher, jurist and social reformer. He is regarded as the founder of modern utilitarianism.
Bentham became a leading theorist in Anglo-American philosophy of law, and a political radical whose ideas influenced the development of welfarism. He advocated individual and economic freedom, the separation of church and state, freedom of expression, equal rights for women, the right to divorce, and the decriminalising of homosexual acts. He called for the abolition of slavery and the death penalty, and for the abolition of physical punishment, including that of children. Though strongly in favour of the extension of individual legal rights, he opposed the idea of natural law and natural rights, calling them “nonsense upon stilts”.
Bentham’s students included his secretary and collaborator James Mill, the latter’s son, John Stuart Mill, the legal philosopher John Austin, as well as influential political figures such as Robert Owen, one of the founders of modern socialism. Bentham has been described as the “spiritual founder” of University College London, though he played little direct part in its foundation. In recent years he has become known as an early advocate of animal rights.
Adam Smith was a Scottish moral philosopher and a pioneer of political economy. One of the key figures of the Scottish Enlightenment, Adam Smith is best known for two classic works: The Theory of Moral Sentiments (1759), and An Inquiry into the Nature and Causes of the Wealth of Nations (1776). The latter, usually abbreviated as The Wealth of Nations, is considered his magnum opus and the first modern work of economics. Smith is cited as the father of modern economics and is still among the most influential thinkers in the field of economics today. In 2009, Smith was named among the “Greatest Scots” of all time, in a vote run by Scottish television channel STV.
Smith studied social philosophy at the
Idealism and Skepticism
Efforts to resolve the dualism of mind and matter, a problem first raised by Descartes, continued to engage philosophers during the 17th and 18th centuries. The division between science and religious belief also occupied them. There, the aim was to preserve the essentials of faith in God while at the same time defending the right to think freely. One view called Deism saw God as the cause of the great mechanism of the world, a view more in harmony with science than with traditional religion. Natural science at this time was striding ahead, relying on sense perception as well as reason, and thereby discovering the universal laws of nature and physics. Such empirical (observation-based) knowledge appeared to be more certain and valuable than philosophical knowledge based upon reason alone.
After Locke philosophers became more skeptical about achieving knowledge that they could be certain was true. Some thinkers who despaired of finding a resolution to dualism embraced skepticism, the doctrine that true knowledge, other than what we experience through the senses, is impossible. Others turned to increasingly radical theories of being and knowledge. Among them was German philosopher Immanuel Kant, probably the most influential of all because he set Western philosophy on a new path that it still follows today. Kant’s view that knowledge of the world is dependent upon certain innate categories or ideas in the human mind is known as idealism.
Leibniz
Gottfried Wilhelm Leibniz (sometimes von Leibniz or Leibnitz) was a German mathematician and philosopher.
German philosopher Gottfried Wilhelm Leibniz, like Spinoza before him, worked in the rationalist (reason-based) tradition to produce a brilliant solution to the problems raised by dualism. Leibniz, a mathematician and statesman as well as a philosopher, developed a remarkably subtle and original system of philosophy that combined the mathematical and physical discoveries of his time with the organic and religious conceptions of nature found in ancient and medieval thought. Leibniz viewed the world as an infinite number of infinitely small units of force, called monads, each of which is a closed world but mirrors all the other monads through its activity, which is perception. All the monads are spiritual entities, but they can combine to form material bodies. Leibniz conceived of God as the Monad of Monads, which creates all other monads and predestines their development.
Leibniz’s theory of the predestination of monads, also called the theory of preestablished harmony, entailed a radical rejection of causality—the view that every effect must have a cause. According to Leibniz, monads do not interact with each other at all, and the appearance of mechanical causality in the natural world is unreal, akin to an illusion. Likewise, there is no room in the universe for free will: Even though we enjoy the illusion of acting freely, all human actions are predetermined by God. Despite these gloomy conclusions, Leibniz’s philosophy was profoundly optimistic because he argued that ours was the best of all possible worlds. He based this belief on considerations about the nature of truth and necessity. French writer Voltaire mocked this viewpoint in Candide (1759), a satirical novel that examines the woes heaped on the world in the name of God.
Berkeley
George Berkeley, also known as Bishop Berkeley (Bishop of Cloyne), was an Anglo-Irish philosopher whose primary achievement was the advancement of a theory he called “immaterialism” (later referred to as “subjective idealism” by others). This theory denies the existence of material substance and instead contends that familiar objects like tables and chairs are only ideas in the minds of perceivers, and as a result cannot exist without being perceived. Thus, as
In the 18th century Irish philosopher and Anglican churchman George Berkeley, like Spinoza before him, rejected both Cartesian dualism and the assertion by Hobbes that only matter is real.
Hume
David Hume was a Scottish philosopher, historian, economist, and essayist, known especially for his philosophical empiricism and skepticism. He was one of the most important figures in the history of Western philosophy and the Scottish Enlightenment. Hume is often grouped with John Locke, George Berkeley, and a handful of others as a British Empiricist.
Whereas
All metaphysical assertions about things that cannot be directly perceived are equally meaningless, Hume claimed, and should be “committed to the flames.” In his analyses of causality and induction, Hume revealed that there is no logical justification for believing that any two events which occur together are connected by cause and effect or for making any inference from past to future. Hume noted that we depend on our past experience whenever we form beliefs about anything that we do not directly perceive and whenever we make predictions about the future. According to the empiricist doctrine of Bacon, Locke, and Berkeley, we can do this because experience teaches us what particular things belong together as causes and effects. Hume, however, argued that this attempt to learn from experience is not at all rational, thus calling into question the reliability of our memories, our reasoning processes, and our ability to learn from past experiences or to make even the smallest predictions about the future—for example, that the sun will rise tomorrow. Though extreme, Hume’s skepticism about philosophical empiricism raised problems about the possibility of knowledge that contemporary philosophers still struggle to resolve.
Kant
Immanuel Kant was a German philosopher from Königsberg in
German philosopher Immanuel Kant was among the first to appreciate Hume’s skepticism, and in response he published the Critique of Pure Reason (1781), widely considered the greatest single work in modern philosophy. In this work Kant made a thorough and systematic analysis of the conditions for knowledge. As an example of genuine knowledge, he had in mind the contributions to physics of English scientist Isaac Newton. In the case of Newtonian physics, reason seemed to have done an effective job of understanding the data supplied by the senses and to have succeeded in postulating universal and necessary laws of nature, such as the law of gravitation and the laws of motion. Kant proposed to explain how such knowledge is possible, thereby providing a complete reply to Hume’s skepticism and answering many of the problems that had plagued Western philosophers since the time of Descartes.
Kant started by making a fresh analysis of the elements of knowledge, asking for the first time an extremely basic question, “How is our experience possible in the first place?” Kant’s predecessors had taken experience for granted. Thus Descartes agreed that we seem to have sensory knowledge of the world but asked whether this knowledge was true or the result of a dream. Similarly, Hume’s skepticism about causation arose when he concluded that we do not encounter causality in our ordinary experience of the world and that any inferences about it, beyond immediate experience, were questionable. Kant’s answer to the skepticism of Descartes and Hume involved certain categories, such as space, time, substance, and causality, which he maintained are essential to our thinking and to our experience of phenomena in the world. These categories he called transcendental. All objects of our knowledge, he concluded, must conform to the human mind’s essential ways of perceiving and understanding—ways that involve the transcendental categories—if they are to be knowable at all. Kant maintained that he had developed a revolutionary hypothesis about knowledge and reality that he believed to be as significant for the future of philosophy as the hypothesis of Copernicus—that the planets orbit the Sun—had been for science.
Kant’s claim that causality, substance, space, and time are forms imposed by the mind gave support to the idealism of Leibniz and Berkeley. Kant, however, made his view a more critical form of idealism by granting the empiricist claim that things-in-themselves—that is, things as they exist outside human experience—are unknowable. Kant therefore limited knowledge to the “phenomenal world” of experience, maintaining that metaphysical beliefs about the soul, the cosmos, and God (the “noumenal world” transcending human experience) are matters of faith rather than of scientific knowledge.
In his ethical writings Kant held that moral principles are categorical imperatives, absolute commands of reason that permit no exceptions and are not related to pleasure or practical benefit. Kant argued that human beings should act as members of an ideal “kingdom of ends” in which every person is treated as an end in himself or herself, and never as a means to someone else’s ends. In addition, everyone should govern their conduct as if their actions were to be made law—a law that applies equally to all without exception. Kant thereby postulated a freedom of action based on moral order and equality. His moral philosophy contributed to modern political ideas about freedom and democracy. Kant was a leading figure of the movement for reason and liberty against tradition and authority, and in his religious teachings he emphasized individual conscience and represented God primarily as a moral ideal.
Kant’s writings constituted a
Johann Gottlieb Fichte was a German philosopher. He was one of the founding figures of the philosophical movement known as German idealism, which developed from the theoretical and ethical writings of Immanuel Kant. Fichte is often perceived as a figure whose philosophy forms a bridge between the ideas of Kant and those of the German Idealist Georg Wilhelm Friedrich Hegel. Recently, philosophers and scholars have begun to appreciate Fichte as an important philosopher in his own right due to his original insights into the nature of self-consciousness or self-awareness. Like Descartes and Kant before him, he was motivated by the problem of subjectivity and consciousness. Fichte also wrote works of political philosophy and is considered one of the fathers of Germaationalism.
François-Marie Arouet, known by his nom de plume Voltaire (pronounced: [vɔl.tɛːʁ]), was a French Enlightenment writer, historian and philosopher famous for his wit and for his advocacy of civil liberties, including freedom of religion, freedom of expression, free trade and separation of church and state. Voltaire was a versatile writer, producing works in almost every literary form, including plays, poems, novels, essays, and historical and scientific works. He wrote more than 20,000 letters and more than 2,000 books and pamphlets. He was an outspoken supporter of social reform, despite strict censorship laws with harsh penalties for those who broke them. As a satirical polemicist, he frequently made use of his works to criticize intolerance, religious dogma, and the French institutions of his day.
Voltaire was one of several Enlightenment figures (along with Montesquieu, John Locke, Richard Price, Jean-Jacques Rousseau, and Émilie du Châtelet) whose works and ideas influenced important thinkers of both the American and French Revolutions.
Charles-Louis de Secondat, baron de
Jean-Jacques Rousseau was a Genevan philosopher, writer, and composer of 18th-century Romanticism of French expression. His political philosophy influenced the French Revolution as well as the overall development of modern political, sociological and educational thought.
His novel Émile: or, On Education is a treatise on the education of the whole person for citizenship. His sentimental novel Julie, or the New Heloise was of importance to the development of pre-romanticism and romanticism in fiction. Rousseau’s autobiographical writings—his Confessions, which initiated the modern autobiography, and his Reveries of a Solitary Walker—exemplified the late 18th-century movement known as the Age of Sensibility, featuring an increasing focus on subjectivity and introspection that has characterized the modern age. His Discourse on the Origin of Inequality and his On the Social Contract are cornerstones in modern political and social thought.
Rousseau was a successful composer of music. He wrote seven operas as well as music in other forms, and he made contributions to music as a theorist.
During the period of the French Revolution, Rousseau was the most popular of the philosophes among members of the Jacobin Club. Rousseau, a Freemason, was interred as a national hero in the Panthéon in
Denis Diderot was a French philosopher, art critic, and writer. He was a prominent person during the Enlightenment and is best known for serving as co-founder and chief editor of and contributor to the Encyclopédie along with Jean le Rond d’Alembert.
Diderot also contributed to literature, notably with Jacques le fataliste et son maître (Jacques the Fatalist and his Master), which emulated Laurence Sterne in challenging conventions regarding novels and their structure and content, while also examining philosophical ideas about free will. Diderot is also known as the author of the dialogue, Le Neveu de Rameau (Rameau’s Nephew), upon which many articles and sermons about consumer desire have been based.
Benjamin Franklin was one of the Founding Fathers of the
For many years he was the British postmaster for the colonies, which enabled him to set up the first national communications network. He was active in community affairs, colonial and state politics, as well as national and international affairs. From 1785 to 1788, he served as governor of
His colorful life and legacy of scientific and political achievement, and status as one of America’s most influential Founding Fathers, have seen Franklin honored on coinage and money; warships; the names of many towns, counties, educational institutions, namesakes, and companies; and more than two centuries after his death, countless cultural references.
Thomas Jefferson was an American Founding Father, the principal author of the Declaration of Independence (1776) and the third President of the
Elected president in what Jefferson called the Revolution of 1800, he oversaw the purchase of the vast
A leader in the Enlightenment, Jefferson was a polymath who spoke five languages fluently and was deeply interested in science, invention, architecture, religion and philosophy, interests that led him to the founding of the
Thomas Paine was an English-American political activist, author, political theorist and revolutionary. As the author of two highly influential pamphlets at the start of the American Revolution, he inspired the American Patriots in 1776 to declare independence from
Born in
Paine lived in
In 1802, he returned to
The Enlightenment Room,
References
1. http://www.answers.com/topic/philosophy#ixzz2ggPxbwQP
2. http://en.wikipedia.org/wiki
3. Copleston F. С. History of Philosophy, 8 vol.
4. Edwards, Paul, Encyclopedia of Philosophy, 8 vol.
