The Age of Reason was a period of great intellectual activity that began in the 1600's and lasted until the late 1700's. The period is also called the Enlightenment. Philosophers of the Age of Reason stressed the use of reason, as opposed to the reliance on authority and scriptural revelation. For them, reason provided means of attaining the truth about the world and of ordering human society to assure human well-being. The leading philosophers included Descartes, Locke, Berkeley, and Hume They also included Jean Jacques Rousseau, Voltaire, Denis Diderot, and other members of a group of French philosophers called the philosophes.
Descartes was a mathematician as well as a philosopher. He invented analytic geometry. Descartes's basic idea was to establish a secure foundation for the sciences, a foundation of the sort he had found for mathematics. He was thus much concerned with the foundations of knowledge, and he started philosophy on its persistent consideration of epistemological problems. Descartes was a mechanist--that is, he regarded all physical phenomena as connected mechanically by laws of cause and effect. Descartes's philosophy generated the problem of how mind and matter are related.
Rationalism was a philosophic outlook that arose in the 1600's. The basic idea of rationalism is that reason is superior to experience as a source of knowledge and that the validity of sense perception must be proved from more certain principles. The rationalists tried to determine the nature of the world and of reality by deduction from premises themselves established as certain a priori. They also stressed the importance of mathematical procedures. The leading rationalists were Rene Descartes, Baruch Spinoza, and Gottfried Leibniz.
One of the earliest philosophers to support the scientific method was Francis Bacon of England. Most historians consider Bacon and Rene Descartes of France to be the founders of modern philosophy. Bacon wrote two influential works, The Advancement of Learning (1605) and Novum Organum (1620). He stated that knowledge was power and that knowledge could be obtained only by the inductive method of investigation. Bacon imagined a new world of culture and leisure that could be gained by inquiry into the laws and processes of nature In describing this world, he anticipated the effects of advances in science, engineering, and technology.
Modern Philosophy. A great cultural movement in Europe called the Renaissance overlapped the end of the Middle Ages and formed a transition between medieval and modern philosophy. The Renaissance began in Italy and lasted from about 1300 to about 1600. It was a time of intellectual reawakening stemming from the rediscovery of ancient Greek and Roman culture During the Renaissance, major advances occurred in such sciences as astronomy, physics, and mathematics. Scholars called humanists stressed the importance of human beings and the study of classical literature as a guide to understanding life Emphasis on science and on humanism led to changes in the aims and techniques of philosophic inquiry. Scholasticism declined, and philosophy was freed of its ties to medieval theology.
Stoic Philosophy and Epicureanism were the two main schools of Greek philosophy that emerged after the death of Aristotle in 322 B.C. Both schools taught that the purpose of knowing is to enable a person to lead the best and most contented life
Aristotle, Plato's greatest pupil, wrote about almost every known subject of his day. He invented the idea of a science and of separate sciences, each having distinct principles and dealing with different subject matter. He wrote on such topics as physics, astronomy, psychology, biology, physiology, and anatomy. Aristotle also investigated what he called "first philosophy," later known as metaphysics.
Aristotle's basic method of inquiry consisted of starting from what we know or think we know and then asking how, what, and why. In his metaphysics, he developed the idea of a first cause, which was not itself caused by anything, as the ultimate explanation of existence Christian theologians later adopted this idea as a basic argument for the existence of God. Aristotle taught that everyone aims at some good. He said that happiness does not lie in pleasure but in virtuous activity. By virtuous activity, he meant behaving according to a mean between extremes. For example, courage is the mean between the extremes of cowardice and foolhardiness. The highest happiness of all, Aristotle believed, was the contemplative use of the mind.
Socrates wanted to replace vague opinions with clear ideas. He often questioned important Athenians and exposed their empty claims to knowledge and wisdom. This practice made him many enemies, and he was put to death as a danger to the state He thus became a symbol of the philosopher who pursued an argument wherever it led to arrive at the truth, no matter what the cost.
Socrates lived in Athens and taught in the streets, market place, and gymnasiums. He taught by a question-and-answer method. Socrates tried to get a definition or precise view of some abstract idea, such as knowledge, virtue, justice, or wisdom. He would use close, sharp questioning, constantly asking "What do you mean?" and "How do you know?" This procedure, called the Socratic method, became the model for philosophic methods that emphasize debate and discussion.
Stoic philosophy was founded by Zeno of Citium. He taught that people should spend their lives trying to cultivate virtue, the greatest good. The Stoics believed in strict determinism--the idea that all things are fated to be Therefore, they said, a wise and virtuous person accepts and makes the best of what cannot be changed. Stoicism spread to Rome There, the chief Stoics included the statesman Marcus Tullius Cicero, the emperor Marcus Aurelius, and the teacher Epictetus.
Socrates left no writings, though he was constantly engaged in philosophic discussion. Our knowledge of his ideas and methods comes mainly from dialogues written by his pupil Plato. In most of the dialogues, Socrates appears as the main character, who leads and develops the process of inquiry.