Editing Natural science (section)

==History==
{{See also|Natural philosophy|History of science}}

Some scholars trace the origins of natural science as far back as pre-literate human societies, where understanding the natural world was necessary for survival.{{sfn|Grant|2007|p=1}} People observed and built up knowledge about the behavior of animals and the usefulness of plants as food and medicine, which was passed down from generation to generation.{{sfn|Grant|2007|p=1}} These primitive understandings gave way to more formalized inquiry around 3500 to 3000 BC in the [[Mesopotamia]]n and [[Ancient Egypt]]ian cultures, which produced the first known written evidence of [[natural philosophy]], the precursor of natural science.{{sfn|Grant|2007|p=2}} While the writings show an interest in astronomy, mathematics, and other aspects of the physical world, the ultimate aim of inquiry about nature's workings was, in all cases, religious or mythological, not scientific.{{sfn|Grant|2007|pp=2–3}}

A tradition of scientific inquiry also emerged in [[Ancient China]], where [[Taoism|Taoist]] [[alchemy|alchemists]] and philosophers experimented with elixirs to [[life extension|extend life]] and cure ailments.{{sfn|Magner|2002|p=3}} They focused on the [[yin and yang]], or contrasting elements in nature; the yin was associated with femininity and coldness, while yang was associated with masculinity and warmth.{{sfn|Magner|2002|pp=3–4}} The five phases – fire, earth, metal, wood, and water – described a cycle of transformations in nature. The water turned into wood, which turned into the fire when it burned. The ashes left by fire were earth.{{sfn|Magner|2002|p=4}} Using these principles, Chinese philosophers and doctors explored human anatomy, characterizing organs as predominantly yin or yang, and understood the relationship between the pulse, the heart, and the flow of blood in the body centuries before it became accepted in the West.{{sfn|Magner|2002|p=5}}

Little evidence survives of how [[Ancient India]]n cultures around the [[Indus River]] understood nature, but some of their perspectives may be reflected in the [[Vedas]], a set of sacred [[Hinduism|Hindu]] texts.{{sfn|Magner|2002|p=5}} They reveal a conception of the universe as ever-expanding and constantly being recycled and reformed.{{sfn|Magner|2002|p=5}} Surgeons in the [[Ayurvedic]] tradition saw health and illness as a combination of three humors: [[wind]], [[bile]] and [[phlegm]].{{sfn|Magner|2002|p=5}} A healthy life resulted from a balance among these humors.{{sfn|Magner|2002|p=5}} In Ayurvedic thought, the body consisted of five elements: earth, water, fire, wind, and space.{{sfn|Magner|2002|p=5}} Ayurvedic surgeons performed complex surgeries and developed a detailed understanding of human anatomy.{{sfn|Magner|2002|p=5}}

[[Pre-Socratic philosophy|Pre-Socratic]] philosophers in [[Ancient Greece|Ancient Greek]] culture brought natural philosophy a step closer to direct inquiry about cause and effect in nature between 600 and 400 BC. However, an element of magic and mythology remained.{{sfn|Grant|2007|p=8}} Natural phenomena such as earthquakes and eclipses were explained increasingly in the context of nature itself instead of being attributed to angry gods.{{sfn|Grant|2007|p=8}} [[Thales|Thales of Miletus]], an early philosopher who lived from 625 to 546 BC, explained earthquakes by theorizing that the world floated on water and that water was the fundamental element in nature.{{sfn|Barr|2006|p=2}} In the 5th century BC, [[Leucippus]] was an early exponent of [[atomism]], the idea that the world is made up of fundamental indivisible particles.{{sfn|Barr|2006|p=3}} [[Pythagoras]] applied Greek innovations in mathematics to astronomy and suggested that the earth was [[sphere|spherical]].{{sfn|Barr|2006|p=3}}

===Aristotelian natural philosophy (400 BC–1100 AD)===
[[File: Aristotle's model of Inheritance.png|thumb|upright=1.3|left|Aristotle's view of inheritance, as a model of the transmission of patterns of movement of the body fluids from parents to child, and of [[Hylomorphism|Aristotelian form]] from the father]]
{{further|Aristotle's biology}}

Later [[Socrates|Socratic]] and [[Plato]]nic thought focused on ethics, morals, and art and did not attempt an investigation of the physical world; Plato criticized pre-Socratic thinkers as materialists and anti-religionists.{{sfn|Grant|2007|pp=21–22}} [[Aristotle]], however, a student of Plato who lived from 384 to 322 BC, paid closer attention to the natural world in his philosophy.{{sfn|Grant|2007|pp=27–28}} In his ''[[History of Animals]]'', he described the inner workings of 110 species, including the [[stingray]], [[catfish]] and [[bee]].{{sfn|Grant|2007|pp=33–34}} He investigated chick embryos by breaking open eggs and observing them at various stages of development.{{sfn|Grant|2007|p=34}} Aristotle's works were influential through the 16th century, and he is considered to be the [[Aristotle's biology|father of biology for his pioneering work in that science]].{{sfn|Grant|2007|pp=34–35}} He also presented philosophies about physics, nature, and astronomy using [[inductive reasoning]] in his works ''[[Physics (Aristotle)|Physics]]'' and ''[[Meteorology (Aristotle)|Meteorology]]''.{{sfn|Grant|2007|pp=37–39, 53}}

[[File:Sanzio 01 Plato Aristotle.jpg|thumb|upright|Plato (left) and Aristotle in [[The School of Athens|a 1509 painting]] by [[Raphael]]. Plato rejected inquiry into natural philosophy as against religion, while his student, Aristotle, created a body of work on the natural world that influenced generations of scholars.]]

While Aristotle considered natural philosophy more seriously than his predecessors, he approached it as a theoretical branch of science.{{sfn|Grant|2007|p=52}} Still, inspired by his work, [[Ancient Rome|Ancient Roman]] philosophers of the early 1st century AD, including [[Lucretius]], [[Seneca the Younger|Seneca]] and [[Pliny the Elder]], wrote treatises that dealt with the rules of the natural world in varying degrees of depth.{{sfn|Grant|2007|p=95}} Many [[Ancient Rome|Ancient Roman]] [[Neoplatonism|Neoplatonists]] of the 3rd to the 6th centuries also adapted Aristotle's teachings on the physical world to a philosophy that emphasized spiritualism.{{sfn|Grant|2007|pp=54, 59}} Early [[medieval]] philosophers including [[Macrobius]], [[Calcidius]] and [[Martianus Capella]] also examined the physical world, largely from a cosmological and [[cosmography|cosmographical]] perspective, putting forth theories on the arrangement of celestial bodies and the heavens, which were posited as being composed of [[aether (classical element)|aether]].{{sfn|Grant|2007|p=103}}

Aristotle's works on natural philosophy continued to be translated and studied amid the rise of the [[Byzantine Empire]] and [[Abbasid Caliphate]].{{sfn|Grant|2007|pp=61–66}}

In the Byzantine Empire, [[John Philoponus]], an Alexandrian Aristotelian commentator and Christian theologian, was the first to question Aristotle's physics teaching. Unlike Aristotle, who based his physics on verbal argument, Philoponus instead relied on observation and argued for observation rather than resorting to a verbal argument.<ref>{{cite web|url=http://homepages.wmich.edu/~mcgrew/philfall.htm|title=John Philoponus, Commentary on Aristotle's Physics, pp|website=homepages.wmich.edu|access-date=2018-04-25|archive-url=https://web.archive.org/web/20160111105753/http://homepages.wmich.edu/~mcgrew/philfall.htm|archive-date=2016-01-11|url-status=dead}}</ref> He introduced the [[theory of impetus]]. John Philoponus' criticism of Aristotelian principles of physics served as inspiration for Galileo Galilei during the [[Scientific Revolution]].<ref>{{cite book|url=https://plato.stanford.edu/archives/spr2016/entries/philoponus/|title=The Stanford Encyclopedia of Philosophy|first=Christian|last=Wildberg|editor-first=Edward N.|editor-last=Zalta|date=8 March 2018|publisher=Metaphysics Research Lab, Stanford University|via=Stanford Encyclopedia of Philosophy|access-date=9 May 2023|archive-date=22 August 2019|archive-url=https://web.archive.org/web/20190822110331/https://plato.stanford.edu/archives/spr2016/entries/philoponus/|url-status=live}}</ref><ref>Lindberg, David. (1992) ''The Beginnings of Western Science''. University of Chicago Press. Page 162.</ref>

A revival in mathematics and science took place during the time of the [[Abbasid Caliphate]] from the 9th century onward, when Muslim scholars expanded upon Greek and [[India]]n natural philosophy.{{sfn|Barr|2006|p=11}} The words ''[[Alcohol (disambiguation)|alcohol]]'', ''[[algebra]]'' and ''[[zenith]]'' all have [[Arabic]] roots.{{sfn|Barr|2006|pp=11–12}}

===Medieval natural philosophy (1100–1600)===
{{see also|Renaissance of the 12th century}}
Aristotle's works and other Greek natural philosophy did not reach the West until about the middle of the 12th century, when works were translated from [[Greek people|Greek]] and Arabic into [[Latin]].{{sfn|Grant|2007|pp=95, 130}} The development of European civilization later in the Middle Ages brought with it further advances in natural philosophy.{{sfn|Grant|2007|p=106}} European inventions such as the [[horseshoe]], [[horse collar]] and [[crop rotation]] allowed for rapid population growth, eventually giving way to urbanization and the foundation of schools connected to monasteries and cathedrals in modern-day [[France]] and [[England]].{{sfn|Grant|2007|pp=106–107}} Aided by the schools, an approach to Christian [[theology]] developed that sought to answer questions about nature and other subjects using logic.{{sfn|Grant|2007|p=115}} This approach, however, was seen by some detractors as [[heresy]].{{sfn|Grant|2007|p=115}} 

By the 12th century, Western European scholars and philosophers came into contact with a body of knowledge of which they had previously been ignorant: a large corpus of works in Greek and Arabic that were preserved by Islamic scholars.{{sfn|Grant|2007|p=130}} Through translation into Latin, Western Europe was introduced to Aristotle and his natural philosophy.{{sfn|Grant|2007|p=130}} These works were taught at new universities in [[Paris]] and [[Oxford]] by the early 13th century, although the practice was frowned upon by the Catholic church.{{sfn|Grant|2007|p=143}} A 1210 decree from the [[Synod]] of Paris ordered that "no lectures are to be held in Paris either publicly or privately using Aristotle's books on natural philosophy or the commentaries, and we forbid all this under pain of ex-communication."{{sfn|Grant|2007|p=143}}

In the late Middle Ages, [[Spain|Spanish]] philosopher [[Dominicus Gundissalinus]] translated a treatise by the earlier Persian scholar [[Al-Farabi]] called ''On the Sciences'' into Latin, calling the study of the mechanics of nature ''Scientia naturalis'', or natural science.{{sfn|Grant|2007|p=155}} Gundissalinus also proposed his classification of the natural sciences in his 1150 work ''On the Division of Philosophy''.{{sfn|Grant|2007|p=155}} This was the first detailed classification of the sciences based on Greek and Arab philosophy to reach Western Europe.{{sfn|Grant|2007|p=155}} Gundissalinus defined natural science as "the science considering only things unabstracted and with motion," as opposed to mathematics and sciences that rely on mathematics.{{sfn|Grant|2007|p=156}} Following Al-Farabi, he separated the sciences into eight parts, including: physics, cosmology, meteorology, minerals science, and plant and animal science.{{sfn|Grant|2007|p=156}}

Later, philosophers made their own classifications of the natural sciences. [[Robert Kilwardby]] wrote ''On the Order of the Sciences'' in the 13th century that classed medicine as a mechanical science, along with agriculture, hunting, and theater, while defining natural science as the science that deals with bodies in motion.{{sfn|Grant|2007|pp=156–157}} [[Roger Bacon]], an English friar and philosopher, wrote that natural science dealt with "a principle of motion and rest, as in the parts of the elements of fire, air, earth, and water, and in all inanimate things made from them."{{sfn|Grant|2007|p=158}} These sciences also covered plants, animals and celestial bodies.{{sfn|Grant|2007|p=158}} 

Later in the 13th century, a Catholic priest and theologian [[Thomas Aquinas]] defined natural science as dealing with "mobile beings" and "things which depend on a matter not only for their existence but also for their definition."{{sfn|Grant|2007|pp=159–163}} There was broad agreement among scholars in medieval times that natural science was about bodies in motion. However, there was division about including fields such as medicine, music, and perspective.{{sfn|Grant|2007|p=234}} Philosophers pondered questions including the existence of a vacuum, whether motion could produce heat, the colors of rainbows, the motion of the earth, whether elemental chemicals exist, and where in the atmosphere rain is formed.{{sfn|Grant|2007|pp=236–237}}

In the centuries up through the end of the Middle Ages, natural science was often mingled with philosophies about magic and the occult.{{sfn|Grant|2007|pp=170–178}} Natural philosophy appeared in various forms, from treatises to encyclopedias to commentaries on Aristotle.{{sfn|Grant|2007|pp=189–190}} The interaction between natural philosophy and [[Christianity]] was complex during this period; some early theologians, including [[Tatian]] and [[Eusebius]], considered natural philosophy an outcropping of pagan Greek science and were suspicious of it.{{sfn|Grant|2007|pp=239–240}} Although some later Christian philosophers, including Aquinas, came to see natural science as a means of interpreting scripture, this suspicion persisted until the 12th and 13th centuries.{{sfn|Grant|2007|pp=241–243}} The [[Condemnations of 1210–1277|Condemnation of 1277]], which forbade setting philosophy on a level equal with theology and the debate of religious constructs in a scientific context, showed the persistence with which Catholic leaders resisted the development of natural philosophy even from a theological perspective.{{sfn|Grant|2007|pp=246–247}} Aquinas and [[Albertus Magnus]], another Catholic theologian of the era, sought to distance theology from science in their works.{{sfn|Grant|2007|p=251}} "I don't see what one's interpretation of Aristotle has to do with the teaching of the faith," he wrote in 1271.{{sfn|Grant|2007|p=252}}

===Newton and the scientific revolution (1600–1800)===
By the 16th and 17th centuries, natural philosophy evolved beyond commentary on Aristotle as more early Greek philosophy was uncovered and translated.{{sfn|Grant|2007|p=274}} The invention of the printing press in the 15th century, the invention of the microscope and telescope, and the [[Protestant Reformation]] fundamentally altered the social context in which scientific inquiry evolved in the West.{{sfn|Grant|2007|p=274}} [[Christopher Columbus]]'s discovery of a new world changed perceptions about the physical makeup of the world, while observations by [[Copernicus]], [[Tyco Brahe]] and [[Galileo]] brought a more accurate picture of the solar system as [[heliocentric]] and proved many of Aristotle's theories about the heavenly bodies false.{{sfn|Grant|2007|p=274–275}} Several 17th-century philosophers, including [[René Descartes]], [[Pierre Gassendi]], [[Marin Mersenne]], [[Nicolas Malebranche]], [[Thomas Hobbes]], [[John Locke]] and [[Francis Bacon]], made a break from the past by rejecting Aristotle and his medieval followers outright, calling their approach to natural philosophy superficial.{{sfn|Grant|2007|pp=276–277}}

[[File:JKepler.jpg|thumb|left|[[Johannes Kepler]] (1571–1630). Kepler's [[Astronomia Nova]] is "the first published account wherein a scientist documents how he has coped with the multitude of imperfect data to forge a theory of surpassing accuracy", therefore laying the groundwork for the scientific method.<ref>{{cite web | url=https://www.nasa.gov/kepler/education/johannes | title=Johannes Kepler: His Life, His Laws and Times | date=24 September 2016 | access-date=1 September 2023 | archive-date=24 June 2021 | archive-url=https://web.archive.org/web/20210624003856/https://www.nasa.gov/kepler/education/johannes/ | url-status=dead }}</ref>]]
The titles of Galileo's work ''Two New Sciences'' and [[Johannes Kepler]]'s ''New Astronomy'' underscored the atmosphere of change that took hold in the 17th century as Aristotle was dismissed in favor of novel methods of inquiry into the natural world.{{sfn|Grant|2007|p=278}} Bacon was instrumental in popularizing this change; he argued that people should use the [[arts]] and sciences to gain dominion over nature.{{sfn|Grant|2007|pp=278–279}} To achieve this, he wrote that "human life [must] be endowed with discoveries and powers."{{sfn|Grant|2007|p=279}} He defined natural philosophy as "the knowledge of Causes and secret motions of things; and enlarging the bounds of Human Empire, to the effecting of all things possible."{{sfn|Grant|2007|p=278}} Bacon proposed that scientific inquiry be supported by the state and fed by the collaborative research of scientists, a vision that was unprecedented in its scope, ambition, and forms at the time.{{sfn|Grant|2007|p=279}} 

Natural philosophers came to view nature increasingly as a mechanism that could be taken apart and understood, much like a complex clock.{{sfn|Grant|2007|pp=280–285}} Natural philosophers including [[Isaac Newton]], [[Evangelista Torricelli]] and [[Francesco Redi]], [[Edme Mariotte]], [[Jean-Baptiste Denis]] and [[Jacques Rohault]] conducted experiments focusing on the flow of water, measuring [[atmospheric pressure]] using a [[barometer]] and disproving [[spontaneous generation]].{{sfn|Grant|2007|pp=280–290}} Scientific societies and scientific journals emerged and were spread widely through the printing press, touching off the [[scientific revolution]].{{sfn|Grant|2007|pp=280–295}} Newton in 1687 published his ''The Mathematical Principles of Natural Philosophy'', or ''Principia Mathematica'', which set the groundwork for physical laws that remained current until the 19th century.{{sfn|Grant|2007|pp=304–306}}

Some modern scholars, including Andrew Cunningham, Perry Williams, and [[Floris Cohen]], argue that natural philosophy is not properly called science and that genuine scientific inquiry began only with the scientific revolution.{{sfn|Grant|2007|p=307}} According to Cohen, "the emancipation of science from an overarching entity called 'natural philosophy is one defining characteristic of the Scientific Revolution."{{sfn|Grant|2007|p=307}} Other historians of science, including [[Edward Grant]], contend that the scientific revolution that blossomed in the 17th, 18th, and 19th centuries occurred when principles learned in the exact sciences of optics, mechanics, and astronomy began to be applied to questions raised by natural philosophy.{{sfn|Grant|2007|p=307}} Grant argues that Newton attempted to expose the mathematical basis of nature – the immutable rules it obeyed – and, in doing so, joined natural philosophy and mathematics for the first time, producing an early work of modern physics.{{sfn|Grant|2007|pp=317–318}}

[[File: Portrait of Sir Isaac Newton, 1689.jpg|thumb|upright|[[Isaac Newton]] is widely regarded as one of the most influential scientists of all time.]]
The scientific revolution, which began to take hold in the 17th century, represented a sharp break from Aristotelian modes of inquiry.{{sfn|Barr|2006|p=26}} One of its principal advances was the use of the [[scientific method]] to investigate nature. Data was collected, and [[repeatability|repeatable]] measurements were made in [[experiment]]s.{{sfn|Barr|2006|pp=26–27}} Scientists then formed [[hypothesis|hypotheses]] to explain the results of these experiments.{{sfn|Barr|2006|p=27}} The hypothesis was then tested using the principle of [[falsifiability]] to prove or disprove its accuracy.{{sfn|Barr|2006|p=27}} The natural sciences continued to be called natural philosophy, but the adoption of the scientific method took science beyond the realm of philosophical conjecture and introduced a more structured way of examining nature.{{sfn|Barr|2006|p=26}}

Newton, an English mathematician and physicist, was a seminal figure in the scientific revolution.{{sfn|Barr|2006|p=33}} Drawing on advances made in astronomy by Copernicus, Brahe, and Kepler, Newton derived the [[Newton's law of universal gravitation|universal law of gravitation]] and [[Newton's laws of motion|laws of motion]].{{sfn|Barr|2006|pp=33–35}} These laws applied both on earth and in outer space, uniting two spheres of the physical world previously thought to function independently, according to separate physical rules.{{sfn|Barr|2006|p=35}} Newton, for example, showed that the [[tide]]s were caused by the gravitational pull of the [[moon]].{{sfn|Barr|2006|p=36}} Another of Newton's advances was to make mathematics a powerful explanatory tool for natural phenomena.{{sfn|Barr|2006|p=37}} While natural philosophers had long used mathematics as a means of measurement and analysis, its principles were not used as a means of understanding cause and effect in nature until Newton.{{sfn|Barr|2006|p=37}}

In the 18th century and 19th century, scientists including [[Charles-Augustin de Coulomb]], [[Alessandro Volta]], and [[Michael Faraday]] built upon Newtonian mechanics by exploring [[electromagnetism]], or the interplay of forces with positive and negative charges on [[electric charge|electrically charged]] particles.{{sfn|Barr|2006|p=48}} Faraday proposed that forces in nature operated in "[[Field (physics)|fields]]" that filled space.{{sfn|Barr|2006|p=49}} The idea of fields contrasted with the Newtonian construct of gravitation as simply "action at a distance", or the attraction of objects with nothing in the space between them to intervene.{{sfn|Barr|2006|p=49}} [[James Clerk Maxwell]] in the 19th century unified these discoveries in a coherent [[Maxwell's equations|theory of electrodynamics]].{{sfn|Barr|2006|p=48}} Using mathematical equations and experimentation, Maxwell discovered that space was filled with charged particles that could act upon each other and were a medium for transmitting charged waves.{{sfn|Barr|2006|p=48}}

Significant advances in chemistry also took place during the scientific revolution. [[Antoine Lavoisier]], a French chemist, refuted the [[phlogiston theory]], which posited that things burned by releasing "phlogiston" into the air.{{sfn|Barr|2006|p=49}} [[Joseph Priestley]] had discovered [[oxygen]] in the 18th century, but Lavoisier discovered that [[combustion]] was the result of [[oxidation]].{{sfn|Barr|2006|p=49}} He also constructed a table of 33 elements and invented modern chemical nomenclature.{{sfn|Barr|2006|p=49}} Formal biological science remained in its infancy in the 18th century, when the focus lay upon the [[Scientific classification|classification and categorization]] of natural life. This growth in [[natural history]] was led by [[Carl Linnaeus]], whose 1735 [[Taxonomy (biology)|taxonomy]] of the natural world is still in use. Linnaeus, in the 1750s, introduced [[Binomial nomenclature|scientific names]] for all his species.{{sfn|Mayr|1982|pp=171–179}}

===19th-century developments (1800–1900)===
[[File: Michelson-Morley experiment (en).svg|thumb|The [[Michelson–Morley experiment]] was used to disprove that light propagated through a [[luminiferous aether]]. This 19th-century concept was then superseded by [[Albert Einstein]]'s [[special theory of relativity]].]]

By the 19th century, the study of science had come into the purview of professionals and institutions. In so doing, it gradually acquired the more modern name of ''natural science.'' The term ''scientist'' was coined by [[William Whewell]] in an 1834 review of [[Mary Somerville]]'s ''On the Connexion of the Sciences''.<ref name=Holmes>{{cite book |last1= Holmes|first1= R|title= The age of wonder: How the romantic generation discovered the beauty and terror of science|date= 2008|publisher= Harper Press|location= London|isbn= 978-0-00-714953-7|page= 449}}</ref> But the word did not enter general use until nearly the end of the same century.{{cn|date=July 2022}}

===Modern natural science (1900–present)===
According to a famous 1923 textbook, ''Thermodynamics and the Free Energy of Chemical Substances'', by the American chemist [[Gilbert N. Lewis]] and the American physical chemist [[Merle Randall]],<ref>{{cite book|title=Thermodynamics and the Free Energy of Chemical Substances |url=https://archive.org/details/thermodynamicsfr00gnle_603 |first1=Gilbert N. |last1=Lewis |first2=Merle |last2=Randall |publisher=McGraw-Hill Book Company |edition=First |others=later Printing edition |date=1923 |asin= B000GSLHZS}}</ref> the natural sciences contain three great branches:

<blockquote>Aside from the logical and mathematical sciences, there are three great branches of ''natural science'' which stand apart by reason of the variety of far reaching deductions drawn from a small number of primary postulates — they are [[mechanics]], [[electrodynamics]], and [[thermodynamics]].<ref>{{cite book|last=Huggins|first=Robert A.|title=Energy storage|url=https://archive.org/details/energystorage00hugg|url-access=limited|date=2010|publisher=Springer|location=New York|isbn=978-1-4419-1023-3|edition=Online-Ausg. |page=[https://archive.org/details/energystorage00hugg/page/n41 13]}}</ref></blockquote>

Today, natural sciences are more commonly divided into life sciences, such as botany and zoology, and physical sciences, which include physics, chemistry, astronomy, and Earth sciences.