Renaissance humanism, with its concern to recover ancient texts, can be seen as backward-looking. It took time for scholars to accept the idea that learning could be advanced rather than recovered. Scientists had to learn to separate their subject from theology, Aristotelian philosophy, Ptolemaic astrology and Galenic medicine.
The humours and the body (See also earlier post.) The difficulties of accommodating new knowledge to ancient categories can be seen in the speculations of Niccolò Leoniceno, professor of medicine at the University of Padua. He decided that what we call the ‘Columbian exchange’, the arrival of syphilis in the Old World, had to be due to a rise in the level of the Italian rivers, notably the Tiber, which disturbed the humours. There is therefore a sense in which the rediscovery of ancient texts confirmed ancient prejudices. But at the same time, the idea of the inexorable laws of nature – rational, comprehensible and divinely ordained - took hold and in time weakened the Church’s assertion that theology was the queen of the sciences.
The new anatomy Andreas Vesalius (1514-1564) trained initially at Louvain where he complained that lecturer who taught Aristotle was
‘a theologian by profession and therefore…ready to mingle his pious views with those of the philosophers'. (Quoted Koenigsberger, Mosse and Bowler, Europe in the Sixteenth Century, Longman, 1989, 419).
From 1537 he was professor of surgery and anatomy at the University of Padua. Unlike his predecessors he believed that surgery had to be grounded in anatomy. Unusually, he always performed dissections himself and produced anatomical charts of the blood and nervous systems as a reference aid for his students, which were widely copied.
In 1539, his supply of dissection material increased when a Paduan judge became interested in Vesalius' work, and made bodies of executed criminals available to him. He was now able make repeated and comparative dissections of humans. This was in marked contrast to Galen, the standard authority on anatomy who, for religious reasons, had been restricted to animals, mainly apes. Vesalius realised that Galen's and his own observations differed, and that humans do not share the same anatomy as apes. In 1543, Vesalius published '
De Humani Corporis Fabrica'. The book was based largely on human dissection, and transformed anatomy into a subject that relied on observations taken directly from human dissections.
The rise of scepticism In time the recovery of ancient knowledge bred more critical ways of thought. Ancient writers often contradicted each other so they could not all be right! And new discoveries undermined
much ancient knowledge. For example, Aristotle’s belief that life could not exist in the southern hemisphere was disproved. The result of the new discoveries was a rise in scepticism, seen most notably in the writings of the French lawyer and essayist,
Michel de Montaigne (1533-92) who argued that doubt and the suspension of all judgment are the finest human achievements. (KMB, 357). In 1576 he ordered a medal to be struck with the inscription
Que sais-je? Montaigne invented a new literary genre (the essai). The
Essays began as a series of classical commonplaces, but became an exploration of his own thoughts and feelings.
‘Je suis moy-mesmes la matière de mon livre’: I am myself the subject of my book.
After his death the manuscript and published essays were incorporated into a definitive edition by his adopted daughter, Marie de Gournay, in 1595. They were translated into English in 1603. Montaigne’s essay ‘On Cannibals’ is the only certain source for
The Tempest. Montaigne’s scepticism led him to two controversial positions: cultural relativism and
fideism. He asserted that we should not condemn cannibals because the practice of cannibalism makes sense in their culture; and because we cannot know religious truth, we should accept unconditionally the authority of the Catholic Church. Some scholars have seen Montaigne as an atheist and his
Essays were placed on the Index of Prohibited Books. The Church was uneasy about his apparent preference of Socrates to Christ. But did this mean that he lacked all religious belief? It has been argued that his scepticism was the product of a particular phase in human history when it was impossible to know matters that are now settled beyond dispute (such as the heliocentric solar system). Under these circumstances, scepticism was a logical position.
‘Lacking our scientific conception of nature, Montaigne was not in a position to say that miracles were impossible… Perhaps in the intellectual climate of a later age he would simply have been an unbeliever…But perhaps in that of his own he could be neither a believer nor an unbeliever wholeheartedly…Unable to conquer his moral objections to unbelief, he stayed within the fold but sometimes looked speculatively out of it.’ (Susan Khin Zaw, Open University)
The idea of progress Relatively early in his career
Francis Bacon (1561-1626) judged that, owing mainly to an undue reverence for the past, the intellectual life of Europe had reached animpasse. He criticized Plato, Aristotle and Galen, and also the modern alchemists for lack of empirical rigour. See
here and
here for more about Bacon. In his 1605 treatise
The Proficience and Advancement of Learning, arguably the first important
philosophical work to be published in English, he set out the revolutionary proposition that knowledge can advance and that through new technical inventions and mechanical discoveries, human life could be improved. He expanded this view with even greater confidence in his
Novum Organum (1620). This was a new model of history – upward and progressive – rather than, as Aristotle had taught, merely cyclical, and it was not universally accepted. In 1611 John Donne wrote, in traditional fashion,
‘Our age is iron, and rusty too’.
In 1597 Bacon famously asserted:
‘Knowledge is power’.
He pioneered what is known as the scientific method of
inductive reasoning, arguing from the specific to the general, as opposed to Aristotle's legacy of deductive (top down) logic. In his
Cognita et Vista (1607) he defined this alternative procedure as one
‘which by slow and faithful toil gathers information from things and brings it into understanding’.
The beginnings of the scientific revolution Copernicus: In 1543 Nicholas
Copernicus published his
De revolutionibus, with a dedication to Pope Paul III and a preface by the Lutheran theologian Osiander. The book produced little controversy at the time. Though it was attacked in 1546 by a Dominican theologican, it did not arouse much opposition because the heliocentric universe was posited as a hypothesis only.
Tycho Brahe (1546-1601): In 1572 a new star (probably a
supernova) appeared in the constellation of Cassiopeia. It grew in brilliance but disappeared after sixteen months. This was followed in 1577 by a comet. From observing and measuring these phenomena the Danish astronomer
Tycho Brahe – who was also a passionate alchemist - proved that the new star was situated far beyond the supposed lunar sphere of the traditional cosmos. He had therefore disproved the Ptolomaic universe.
Johannes Kepler: His findings were taken up by
Johannes Kepler (1571-1630) (below) who between 1601 and 1609 worked out the laws of planetary motion. Like Brahe, Kepler was an astrologer.
His neoplatonic mysticism led him to see the sun as motive force of the planets though his calculations forced him to abandon the Aristotelian belief that planetary motion was circular. After a long struggle he came to the (correct) conclusion that planetary motion was
elliptical.
Galileo Galilei: In 1609 Galileo, heard about the newly invented
telescope, constructed his own crude instrument and began to examine the heavens. He quickly discovered that the moon was covered with mountains and pitted with craters rather then being the perfect sphere envisaged by Aristotle. On 7 January 1610 he made an even more
sensational discovery when he discovered the four satellites around Jupiter than are now named in his honour. He finally determined that what he was observing were not stars, but planetary bodies that were in orbit around Jupiter. In 1610 he published
Siderius Nuncius (The Starry Messenger).
'I should disclose and publish to the world the occasion of discovering and observing four Planets, never seen from the beginning of the world up to our own times, their positions, and the observations made during the last two months about their movements and their changes of magnitude; and I summon all astronomers to apply themselves to examine and determine their periodic times, which it has not been permitted me to achieve up to this day . . . On the 7th day of January in the present year, 1610, in the first hour of the following night, when I was viewing the constellations of the heavons through a telescope, the planet Jupiter presented itself to my view, and as I had prepared for myself a very excellent instrument, I noticed a circumstance which I had never been able to notice before, namely that three little stars, small but very bright, were near the planet; and although I believed them to belong to a number of the fixed stars, yet they made me somewhat wonder, because they seemed to be arranged exactly in a straight line, parallel to the ecliptic, and to be brighter than the rest of the stars, equal to them in magnitude . . .When on January 8th, led by some fatality, I turned again to look at the same part of the heavens, I found a very different state of things, for there were three little stars all west of Jupiter, and nearer together than on the previous night.' 'I therefore concluded, and decided unhesitatingly, that there are three stars in the heavens moving about Jupiter, as Venus and Mercury around the Sun; which was at length established as clear as daylight by numerous other subsequent observations. These observations also established that there are not only three, but four, erratic sidereal bodies performing their revolutions around Jupiter.'
A time of confusion? Who to believe: Catholics or Protestants? Aristotelians or anti-Aristotelians?
John Donne - Catholic turned Anglican, man-about-town turned dean of St Paul's perfecty sums up the
confusions of the new age:
And new philosophy calls all in doubt, The element of fire is quite put out, The sun is lost, and th'earth, and no man's wit Can well direct him where to look for it. And freely men confess that this world's spent, When in the planets and the firmament They seek so many new; they see that this Is crumbled out again to his atomies. 'Tis all in pieces, all coherence gone, All just supply, and all relation; Prince, subject, father, son, are things forgot, For every man alone thinks he hath got To be a phoenix…
In 1539, his supply of dissection material increased when a Paduan judge became interested in Vesalius' work, and made bodies of executed criminals available to him. He was now able make repeated and comparative dissections of humans. This was in marked contrast to Galen, the standard authority on anatomy who, for religious reasons, had been restricted to animals, mainly apes. Vesalius realised that Galen's and his own observations differed, and that humans do not share the same anatomy as apes. In 1543, Vesalius published 'De Humani Corporis Fabrica'. The book was based largely on human dissection, and transformed anatomy into a subject that relied on observations taken directly from human dissections. The rise of scepticism In time the recovery of ancient knowledge bred more critical ways of thought. Ancient writers often contradicted each other so they could not all be right! And new discoveries undermined 
much ancient knowledge. For example, Aristotle’s belief that life could not exist in the southern hemisphere was disproved. The result of the new discoveries was a rise in scepticism, seen most notably in the writings of the French lawyer and essayist, Michel de Montaigne (1533-92) who argued that doubt and the suspension of all judgment are the finest human achievements. (KMB, 357). In 1576 he ordered a medal to be struck with the inscription Que sais-je? Montaigne invented a new literary genre (the essai). The Essays began as a series of classical commonplaces, but became an exploration of his own thoughts and feelings.
philosophical work to be published in English, he set out the revolutionary proposition that knowledge can advance and that through new technical inventions and mechanical discoveries, human life could be improved. He expanded this view with even greater confidence in his Novum Organum (1620). This was a new model of history – upward and progressive – rather than, as Aristotle had taught, merely cyclical, and it was not universally accepted. In 1611 John Donne wrote, in traditional fashion, 
His neoplatonic mysticism led him to see the sun as motive force of the planets though his calculations forced him to abandon the Aristotelian belief that planetary motion was circular. After a long struggle he came to the (correct) conclusion that planetary motion was elliptical. Galileo Galilei: In 1609 Galileo, heard about the newly invented 
telescope, constructed his own crude instrument and began to examine the heavens. He quickly discovered that the moon was covered with mountains and pitted with craters rather then being the perfect sphere envisaged by Aristotle. On 7 January 1610 he made an even more sensational discovery when he discovered the four satellites around Jupiter than are now named in his honour. He finally determined that what he was observing were not stars, but planetary bodies that were in orbit around Jupiter. In 1610 he published Siderius Nuncius (The Starry Messenger). 
confusions of the new age: 