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Francis Bacon and the scientific revolution

The Four Humors, from Deutche Kalendar, 1498 (The Morgan Library & Museum, New York)

How do we know that something is true?

The word science comes from the latin root scientia, meaning knowledge. But where does the knowledge that makes up science come from? How do you ever really know that something is true?
For instance, modern science tell us that some types of disease spread through tiny organisms. Medieval people believed instead that sickness arose from an imbalance of the body’s four humors. How do we know with certainty that modern science is correct? Microscopes enable us to see the germs that cause sickness, but when we look through microscopic lenses to examine microbes, how do we know our understanding of what they are and what they are doing is true? Of course, medieval philosophers did not have microscopic lenses—but if they did, they very likely would have disagreed with our modern understanding of disease. Believing in the inaccuracy of the human senses, and moreover of the human mind's inability to correctly judge anything, medieval knowledge instead privileged ancient texts as the best way of making sense of the world.
Francis Bacon, c. 1622, oil on canvas, 470 x 610 cm (Dulwich Picture Gallery, London)

Sir Francis Bacon

In 1620, around the time that people first began to look through microscopes, an English politician named Sir Francis Bacon developed a method for philosophers to use in weighing the truthfulness of knowledge. While Bacon agreed with medieval thinkers that humans too often erred in interpreting what their five senses perceived, he also realized that people's sensory experiences provided the best possible means of making sense of the world. Because humans could incorrectly interpret anything they saw, heard, smelled, tasted, or felt, Bacon insisted that they must doubt everything before assuming its truth.

Testing hypotheses

In order to test potential truths, or hypotheses, Bacon devised a method whereby scientists set up experiments to manipulate nature and attempt to prove their hypotheses wrong. For example, in order to test the idea that sickness came from external causes, Bacon argued that scientists should expose healthy people to outside influences such as coldness, wetness, or other sick people to discover if any of these external variables resulted in more people getting sick. Knowing that many different causes for sickness might be missed by humans who are unable or unwilling to perceive them, Bacon insisted that these experiments must be consistently repeated before truth could be known: a scientist must show that patients exposed to a specific variable more frequently got sick again, and again, and again.
Frontispiece for the Opere di Galileo Galilei, 1656, etching, 17.8 x 24.9 (The Museum of Fine Arts, Houston). Galileo is shown kneeling before personifications of mathematics, who holds a compass; astronomy, with the crown of stars; and optics.Although modern scientists have revised many of the truths adopted by Bacon and his contemporaries, we still utilize Bacon's 1620 method of proving knowledge to be true via doubt and experimentation. Bacon's philosophical work marks a very significant breakthrough for the study of the world around us, but it is important to stress that this method of investigation was not conceived in a vacuum. Rather, Bacon's work should be seen as a part of a widespread cultural revolution accelerated by the rise of the printing press in the 15th century.

Importance of the printing press

Advances in the ability to disseminate new ideas by making standardized letters, numbers, and diagrams repeatable allowed for an unprecedented level of cooperation among philosophers who could now build on each other's ideas over long periods of time. It would be difficult to overstate the effect of the print revolution.
Astronomers such as Copernicus and Galileo began to share and build upon their experiments, and religious reformers began to publicize new—and increasingly radical—Protestant ideas. In a mutually beneficial relationship, the Protestant Reformation and the Scientific Revolution encouraged philosophers to discover all they could about nature as a way to learn more about God, an undertaking that promoted a break with past authorities.

A direct engagement with nature

Artisans and craftspeople soon began engaging in the new natural philosophy, exemplifying the fact that a monumental shift in what constituted evidence for truth was under way. Not only did Renaissance artisans create lenses to see, tools to measure, and artworks to replicate the natural world, but by the 16th century, they began to publish philosophical treatises asserting that through the imitation and reproduction of nature in their arts, they were able to achieve a state of direct engagement with nature. Rather than taking knowledge from ancient sources, they argued that true knowledge came from direct experience. Alchemists likewise prioritized direct engagement with nature. In using fire to divide elements into their "smallest" components—and discovering that there were more than four of them—alchemists promoted the revolutionary idea that observation of nature itself, rather than reliance on ancient authorities, provided the best foundation for knowledge.
Attributed to Bernard Palissy, Oval Basin, c. 1550, lead-glazed earthenware, 18 7/8 x 14 1/2" (The J. Paul Getty Museum, Los Angeles)

The Royal Society

These new ideas crystallized with the work of Francis Bacon. In his work as a politician, he called for the development of an institution that would promote and regulate the acquisition of knowledge derived from observation. After considerable delay caused by a civil war and the execution of King Charles I, the Royal Society for Improving Natural Knowledge was founded in 1660. A gentleman's club composed of tinkering aristocrats, the Royal Society promoted Bacon's principles of exact observation and measurement of experiments in its periodical, Philosophical Transactions of the Royal Society, generally credited as being the first scientific journal.
Frontispiece to Thomas Sprat, The History of the Royal-Society of London, etching by Winceslaus Hollar, after John Evelyn, 1667. "The book was a manifesto of the Society's aims and methods....primarily aimed at the king in the (unrealised) hope that he would fund their future activities. The frontispiece flatters Charles II by presenting him as a classical bust being wreathed by an allegorical figure of Fame. The Society President, Viscount Brouncker, points to the Latin inscription 'Charles II founder and Patron of the Royal Society.' Francis Bacon, gesturing towards an array of scientific instruments, is indentified as the 'Renewer of Arts'." (from the National Portrait Gallery, London)
Once Bacon's philosophies regarding experimentation and observation came to be accepted, people began using them to harness nature for profit. The study of nature came to be less about changing traditional attitudes and beliefs and more about stimulating the economy. By the end of the following century, the Scientific Revolution had given birth to an Industrial Revolution that dramatically transformed the daily lives of people around the world. Western society has been moving forward on Bacon's model for the past three hundred years. Perhaps though, we are in danger of forgetting the vital role doubt played in Bacon's philosophy. Even with powerful microscopes, there is still a lot that human senses miss.
Essay by Dr. Kathryn Wolford
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  • aqualine ultimate style avatar for user SunnySherlock
    I have heard that Francis Bacon invented the scientific method, but I have also heard that it began with Aristotle. Is this true?
    (5 votes)
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    • duskpin ultimate style avatar for user Миленa
      The scientific method is inseparable from science. So the earliest examples of its use have been found in Ancient Egyptian manuscripts. Aristotle further developed it by introducing an inductive-deductive method. (Induction = making a general rule from a set of observations; Deduction = predicting observations based on a general rule). However, he mostly ignored induction as a method for scientific inquiry (even though that's what we use today).

      The modern scientific method emerged in the Middle Ages - first with Arabic thinkers such as Ibn al-Haytham and Ibn Sina, and later with European thinkers such as Robert Grosseteste. Francis Bacon is important because he was the scientific method's great proponent. He argued with those who believed in Aristotle's method, instead advocating a lot of experimentation to prove things. Because that is what we use today, we call him the "father of empiricism."

      I hope that helps, Sarah :)

      To learn more: http://en.wikipedia.org/wiki/History_of_scientific_method
      (13 votes)
  • female robot grace style avatar for user Dea
    were there are non Europeans who contributes to the scientific revolution?
    (4 votes)
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    • duskpin ultimate style avatar for user Миленa
      Yes! One of the greatest contributes were the Arabs. The Arabs took Greek philosophy, and then they made their own additional discoveries in medicine, philosophy, optics, mathematics, etc. The words alcohol, chemistry, algebra, and algorithm are all derived from Arabic.

      In the 12th century, Europeans translated the works of the Arabs into Latin, and made the Latin translations and integral part of the university curriculum. Europe built off from there. Thanks to the internalization of Greco-Arabic science, late scientists of the 16th and 17th centuries had something to reflect on and to reject.

      The Indian civilization deserves honorable mention: they did many things, and most importantly, developed the number system we use today. The number 3745 in Roman numerals is MMMDCCXLV. Complicated, right? Now imagine doing 24,928 in Roman numerals! Indian numerals are MUCH easier to work with and helped make writing numbers SO much easier.

      I'm reading a fascinating book now called Florence & Baghdad: Renaissance Art and Arab Science. The book argues that the development of linear perspective by Brunelleschi was made only thanks to developments in optics by the Arab scientist Alhazen. It's really fascinating, and a great reminder that so much of Europe's science and culture was built off the work of Islamic thinkers.
      (8 votes)
  • spunky sam blue style avatar for user mohitpriya16
    What inspired sir Francis Bacon.
    (3 votes)
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    • duskpin ultimate style avatar for user Миленa
      British universities such as Oxford and Cambridge had a long tradition of empirical science. Previous scientists such as Robert Grossetesste, Roger Bacon, Richard Swineshead and the Oxford Calculators, etc. promoted using empiricism to understand nature. The experiments of these medieval scientists made important contributions to our understanding of optics, inertia, and how velocity and acceleration relate. Bacon was a great promoter of this tradition.
      (6 votes)
  • blobby green style avatar for user Abdishakur
    According to Francis Bacon, why are we using science incorrectly?
    (3 votes)
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  • blobby green style avatar for user Philippos
    Nice article but what does it have to do with Baroque art really? How does it fit/relate to the general topic? Thank you.
    (2 votes)
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  • piceratops seed style avatar for user claire_lightfoot
    This article appears to present Bacon as, in Farrigton's words, the 'Father of Industrial science'. There seems to be no question here of the relevance of Bacon's role in the scientific changes of the 17th C. However, in class, my lecturer stressed that there was considerable debate about Bacon's importance as a promotor of empirical methodology - is this "true"? Can it be known to what extent people listened to him? Particularly considering that, as I understand it, he conducted very little experiments himself.
    (2 votes)
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  • starky tree style avatar for user Hillary
    In the second-to-last paragraph, perhaps the sentence, "After considerable delay... founded in 1660" could be improved with a comma, "After considerable delay[,] cause[d] by a civil war and the execution of King Charles I, the Royal Society for Improving Natural Knowledge was founded in 1660."
    (3 votes)
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    • marcimus pink style avatar for user Abby
      "Vocabulary from Classical Roots C" by Norma Fifer and Nancy Flowers says,"In the Middle Ages, people were classified according to four groups of "humors" or temperaments, determined by fluids in the body:sanguine( blood), "cheerful; phlegmatic (phlegm), "sluggish"; choleric, (yellow bile), "easily angered"; and melancholy (black bile),"gloomy". Gross.
      (1 vote)
  • blobby green style avatar for user saxarova14
    This text was very interesting to me. I didn't know that Bacon was the founder of the scientific method. Also, this text made me think about the reliability of our senses. Our world is very complex, and how can we be sure that we are correctly interpreting what we see? Apparently, I will never get an answer to this question. All we can do is take a critical approach to any information we hear. As a future scientist, I am aware of the importance of the scientific method. We must check every phenomenon and any of our hypotheses, approach the issue with an open mind. Perhaps in the future we will be able to invent devices that will complement our senses. However, can we interpret them correctly?
    And one question: Are there other philosophers dealing with this problem?
    (2 votes)
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    • blobby green style avatar for user Новикова Тамара
      Answering your question, Francis Bacon wasn't the only natural philosopher promoting the importance and possibility of a skeptical methodology. In 1689, an English philosopher and physician John Locke published An Essay Concerning Human Understanding, the main statement of whom was the impossibility to have any knowledge other than the one based upon experience. Bacon and Locke are two principal figures of empiricism - a philosophical theory that rejects innate ideas and states that knowledge primarily comes from experiences gathered through the five senses - but they weren't the only ones. Empiricism was usually opposed to rationalism - another branch of epistemology with different criteria of truth. Rationalists stated that "..certain truths exist, and the intellect can directly grasp these truths". You can further explore these theories if you are interested.

      The Baconian method itself was further developed and promoted mainly by another English philosopher, John Stuart Mill. Although it didn't end up having any long-lasting influence, the general idea of the importance and possibility of a skeptical methodology was supported by many scientists and philosophers throughout the centuries. Theoretical works by Francisco Sanches, George Berkeley, David Hume, and C. S. Peirce had formed the modern scientific method as we know it.
      (3 votes)
  • piceratops ultimate style avatar for user old_english_wolfe
    This was a good article, thanks to the writer. My question is, with the ongoing claim that Bacon devised the scientific method, are there any thoughts on the sometimes-touted Arabic philosopher Alhazen (http://en.wikipedia.org/wiki/Alhazen), who in the 900's developed a scientific method? Obviously Bacon was a major factor in the development of European science, but was Alhazen the true 'first' developer of a scientific method?
    (5 votes)
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  • blobby green style avatar for user Новикова Тамара
    At the very beginning of the text, the author mentions that medieval people believed that sicknesses arose from the imbalance of the body's four humors. Can someone tell me more about it? I'm briefly familiar with the overall concept but don't know much in detail.
    (2 votes)
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    • blobby green style avatar for user Darya Shalapova
      The four humors—black bile, yellow bile, blood, and phlegm—represented different qualities: while black bile was cold and dry and yellow bile was hot and dry, blood was hot and wet and phlegm was cold and wet. Given these combinations, the humors could be matched onto the four seasons, the four elements, and—here's the mental health bit—four different emotional characteristics. The ancient names for these humor—melancholic (black bile), choleric (yellow bile), sanguine (blood), and phlegmatic (phlegm)—represented different temperaments, and still do. Melancholic people are despondent and gloomy. Choleric people are bad-tempered. Sanguine people are courageous, hopeful, and amorous. Phlegmatic people are calm, cool, and unemotional.
      Classical medicine was all about balancing these humors by changing diet, lifestyle, occupation, climate, or by administering medicine. A cold and wet cucumber might help to redress the balance in a feverish individual, as might bloodletting. This was as true for mental illness as it was for somatic diseases. So, if someone was melancholic, they suffered from an excess of black bile; if they were manic, it was either too much blood or yellow bile that was the problem. Balancing one's lifestyle, therefore, was central to one's well-being.
      (3 votes)