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William Harvey (1578-1657 CE) was born in Folkstone, England, and educated at Canterbury and Cambridge. Intending to enter the medical profession, he enrolled at Padua, Italy. He practiced successfully in London, and in 1615 was appointed Lecturer in Anatomy to the Royal College of Physicians. Harvey was the first to show that the heart circulated all of the blood continuously around two great loops—one passing through the lungs, the other through the rest of the body. He published this theory in 1628, in his book The Motion of the Heart and Blood, which established the scientific method in physiology.



Hugo Grotius (1583-1645) or Huig van Groot was born in Delft, Holland and educated at Leiden, where he obtained the degree of Doctor of Law. In 1604 he wrote De Jure Praedo, which was concerned with the legal aspects of seizure, which formed the basis for his most famous work on the law of nature and the justification for war (published in 1625).  Grotius found wars undertaken for defense, indemnification, or punishment to be justifiable. He found many more unjustifiable causes for war: pretexts used to cover up robbery or land theft, falsely justified pre-emptive wars, religious wars, claims based on false title, desire for emigration, exercise of individual rights, promotion of slavery, display of courage or valor, and wars for private interests. Grotius also developed an argument for freedom of the seas.



René Descartes (1596-1650] was born at La Haye, Touraine, France. After initial mathematical studies, he took up army service in various parts of Europe. In 1629, Descartes moved to Holland, to investigate and write about philosophy, physics, musical theory, and mathematics. His skeptical approach led him to believe his only sure knowledge was that he thought and that this entailed that he existed. He postulated a form of dualism whereby mind and body were totally different but interacted through the pineal gland. These two aspects of his thought—skepticism and dualism—became an integral part of Western philosophy. His invention of coordinate geometry was a significant mathematical advance.



Baltasar Gracián Y Morales (1601-1658) was born in Calatayud, Spain, and joined the Society of Jesus in 1619. Initially he wrote several books defining the qualities of the ideal man and offering a system of rules that would lead to the ideal life. In El héroe he described a political superman that he conceived as a Christian answer to Machiavelli’s Prince. From this and other works were extracted some 300 aphorisms that were published as El Oráculo manual, or The Art of Worldly Wisdom.



John Locke (1632-1704) was born England. He obtained a degree at Oxford and became confidential secretary to Lord Shaftesbury (at one time Chancellor of the Exchequer). Both fled to Holland, where Locke wrote most of his philosophical works. He published the majority of his ideas after he returned to England in 1688. Locke was concerned with what one could legitimately claim to know. As such, he is regarded as the father of empirical philosophy. He defined the legitimate spheres of action of church and state, claiming that they were quite separate. Locke argued that sovereign power derived solely from the people. He thus put forward many of the ideas incorporated in the American Revolution.



Isaac Newton (1642-1727) was born in Lincolnshire, England. After graduating at Trinity College, Cambridge, he remained there to carry out optical and chemical experiments and begin development of the calculus. Throughout his life he maintained a deep interest in theology, numerology, and chemistry. Newton first published his superb universal theory of gravitation in 1686 and 1687. From three laws he calculated planetary and satellite orbits accurately and described many other astronomical effects. Newton later became Master of the Mint. He was elected President of the Royal Society in 1703, holding the office for 25 years. During this period he continued his mathematical studies and did much to set the course of experimental research in the 18th century.


Sor Juana

Sor Juana Inés de la Cruz (1648-1695) was born at San Miguel de Nepantla, Mexico.

At age 12 she was recognized as an intellectual prodigy and joined the court of the Viceroy. She entered a convent in 1669, where she  continued to write poetry and carols, two secular plays, and a sacramental play. A theological argument of hers was published without permission, accompanied by an admonishing letter. In her reply, Sor Juana made an eloquent plea for the education of women, pointing out the many biases against them, the waste of talent, and the contributions educated women could make to society.  This was at a time when education of women was considered unwise. 




Francois Marie Arouet de Voltaire (1694-1778) was born in Paris, France. From the age of ten until seventeen he was educated at the College Louis-le-Grand, managed by the Jesuits.  A succession of plays made him the most famous playwright in France. Exiled to England in 1725, he  returned to Paris after three years as a serious philosopher and advocate of justice. His subsequent Letters Concerning the English Nation has been considered the inspiration for the growth of liberal thought in continental Europe. He continued to write  poetry, plays and essays, and also wrote on science, metaphysics and history. The publication of his most famous stories began with Zadig in 1747, followed by Micromegas in 1752, and Candide in 1759, his masterpiece. After 1758 he wrote the Philosophical Dictionary and intensified his crusade on behalf of justice.


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