SCIENCE

Science

Study and knowledge

This article is about the general term. For other uses, see Science (disambiguation).

Science[nb 1][1]:58[2] is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.[nb 2]

Contemporary science is typically subdivided into the natural sciences, which study the material universe; the social sciences, which study people and societies; and the formal sciences, which study logic and mathematics. The formal sciences are often excluded as they do not depend on empirical observations.[3] Disciplines which use science, like engineering and medicine, may also be considered to be applied sciences.[4]

From classical antiquity through the 19th century, science as a type of knowledge was more closely linked to philosophy than it is now, and in the Western world the term "natural philosophy" once encompassed fields of study that are today associated with science, such as astronomy, medicine, and physics.[5][nb 3] However, during the Islamic Golden Age foundations for the scientific method were laid by Ibn al-Haytham in his Book of Optics.[6][7][8][9][10] While the classification of the material world by the ancient Indians and Greeks into air, earth, fire and water was more philosophical, medieval Middle Easterns used practical and experimental observation to classify materials.[11]

In the 17th and 18th centuries, scientists increasingly sought to formulate knowledge in terms of physical laws. Over the course of the 19th century, the word "science" became increasingly associated with the scientific method itself as a disciplined way to study the natural world. It was during this time that scientific disciplines such as biology, chemistry, and physics reached their modern shapes. That same time period also included the origin of the terms "scientist" and "scientific community", the founding of scientific institutions, and the increasing significance of their interactions with society and other aspects of culture.[12][13]

The scale of the universe mapped to the branches of science, with formal sciences as the foundation.[14]: Vol.1, Chaps.1,2,&3.

History

Main article: History of science

Science in a broad sense existed before the modern era and in many historical civilizations.[nb 4] Modern science is distinct in its approach and successful in its results, so it now defines what science is in the strictest sense of the term.[15]

Science in its original sense was a word for a type of knowledge rather than a specialized word for the pursuit of such knowledge. In particular, it was the type of knowledge which people can communicate to each other and share. For example, knowledge about the working of natural things was gathered long before recorded history and led to the development of complex abstract thought. This is shown by the construction of complex calendars, techniques for making poisonous plants edible, and buildings such as the Pyramids. However, no consistent conscientious distinction was made between knowledge of such things, which are true in every community, and other types of communal knowledge, such as mythologies and legal systems.

Antiquity

See also: Nature (philosophy)

Maize, known in some English-speaking countries as corn, is a large grain plant domesticated by indigenous peoples in Mesoamerica in prehistoric times

Before the invention or discovery of the concept of "nature" (ancient Greek phusis) by the Pre-Socratic philosophers, the same words tend to be used to describe the natural "way" in which a plant grows,[16] and the "way" in which, for example, one tribe worships a particular god. For this reason, it is claimed these men were the first philosophers in the strict sense, and also the first people to clearly distinguish "nature" and "convention."[17]: p.209 Science was therefore distinguished as the knowledge of nature and things which are true for every community, and the name of the specialized pursuit of such knowledge was philosophy — the realm of the first philosopher-physicists. They were mainly speculators or theorists, particularly interested in astronomy. In contrast, trying to use knowledge of nature to imitate nature (artifice or technology, Greek technē) was seen by classical scientists as a more appropriate interest for lower class artisans.[18] A clear-cut distinction between formal (eon) and empirical science (doxa) was made by the pre-Socratic philosopher Parmenides (fl. late sixth or early fifth century BCE). Although his work Peri Physeos (On Nature) is a poem, it may be viewed as an epistemological essay on method in natural science. Parmenides' ἐὸν may refer to a formal system or calculus which can describe nature more precisely than natural languages. "Physis" may be identical to ἐὸν.[19]

Aristotle, 384 BCE – 322 BCE, one of the early figures in the development of the scientific method[20]

A major turning point in the history of early philosophical science was the controversial but successful attempt by Socrates to apply philosophy to the study of human things, including human nature, the nature of political communities, and human knowledge itself. He criticized the older type of study of physics as too purely speculative and lacking in self-criticism. He was particularly concerned that some of the early physicists treated nature as if it could be assumed that it had no intelligent order, explaining things merely in terms of motion and matter. The study of human things had been the realm of mythology and tradition, however, so Socrates was executed as a heretic.[21]: 30eAristotle later created a less controversial systematic programme of Socratic philosophy which was teleological and human-centred. He rejected many of the conclusions of earlier scientists. For example, in his physics, the sun goes around the earth, and many things have it as part of their nature that they are for humans. Each thing has a formal cause and final cause and a role in the rational cosmic order. Motion and change is described as the actualization of potentials already in things, according to what types of things they are. While the Socratics insisted that philosophy should be used to consider the practical question of the best way to live for a human being (a study Aristotle divided into ethics and political philosophy), they did not argue for any other types of applied science.

Aristotle maintained the sharp distinction between science and the practical knowledge of artisans, treating theoretical speculation as the highest type of human activity, practical thinking about good living as something less lofty, and the knowledge of artisans as something only suitable for the lower classes. In contrast to modern science, Aristotle's influential emphasis was upon the "theoretical" steps of deducing universal rules from raw data and did not treat the gathering of experience and raw data as part of science itself.[nb 5]

Medieval science

De potentiis anime sensitive, Gregor Reisch (1504) Margarita philosophica. Medieval science postulated a ventricle of the brain as the location for our common sense,[22] where the forms from our sensory systems commingled.

Ibn al-Haytham (Alhazen), 965–1039 Basra, Buyid Emirate. The Muslim scholar who is considered by some to be the father of modern scientific methodology due to his emphasis on experimental data and reproducibility of its results.[23][nb 6]

During late antiquity and the early Middle Ages, the Aristotelian approach to inquiries on natural phenomena was used. Some ancient knowledge was lost, or in some cases kept in obscurity, during the fall of the Roman Empire and periodic political struggles. However, the general fields of science (or "natural philosophy" as it was called) and much of the general knowledge from the ancient world remained preserved through the works of the early Latin encyclopedists like Isidore of Seville. In the Byzantine empire, many Greek science texts were preserved in Syriac translations done by groups such as the Nestorians and Monophysites.[24] Many of these were later on translated into Arabic under the Caliphate, during which many types of classical learning were preserved and in some cases improved upon.[24][nb 7]

The House of Wisdom was established in Abbasid-era Baghdad, Iraq.[25] It is considered to have been a major intellectual center during the Islamic Golden Age, where Muslim scholars such as al-Kindi and Ibn Sahl in Baghdad and Ibn al-Haytham in Cairo flourished from the ninth to the thirteenth centuries until the Mongol sack of Baghdad. Ibn al-Haytham, known later to the West as Alhazen, furthered the Aristotelian viewpoint[26] by emphasizing experimental data.[nb 8][27]

In the later medieval period, as demand for translations grew (for example, from the Toledo School of Translators), western Europeans began collecting texts written not only in Latin, but also Latin translations from Greek, Arabic, and Hebrew. In particular, the texts of Aristotle, Ptolemy,[nb 9] and Euclid, preserved in the Houses of Wisdom, were sought amongst Catholic scholars. In Europe, the Latin translation of Alhazen's Book of Optics directly influenced Roger Bacon (13th century) in England, who argued for more experimental science as demonstrated by Alhazen. By the late Middle Ages, a synthesis of Catholicism and Aristotelianism known as Scholasticism was flourishing in western Europe, which had become a new geographic center of science, but all aspects of scholasticism were criticized in the 15th and 16th centuries.

Renaissance and early modern science

Main article: Scientific revolution

Galen (129–c. 216) noted the optic chiasm is X-shaped. (Engraving from Vesalius, 1543)

Medieval science carried on the views of the Hellenist civilization of Socrates, Plato, and Aristotle, as shown by Alhazen's lost work A Book in which I have Summarized the Science of Optics from the Two Books of Euclid and Ptolemy, to which I have added the Notions of the First Discourse which is Missing from Ptolemy's Book from Ibn Abi Usaibia's catalog, as cited in (Smith 2001).:91(vol.1),p.xv Alhazen conclusively disproved Ptolemy's theory of vision, but he retained Aristotle's ontology; Roger Bacon, Vitello, and John Peckham each built up a scholastic ontology upon Alhazen's Book of Optics, a causal chain beginning with sensation, perception, and finally apperception of the individual and universal forms of Aristotle.[28] This model of vision became known as Perspectivism, which was exploited and studied by the artists of the Renaissance.

Galileo Galilei, father of modern science.[29]: Vol. 24, No. 1, p. 36

A. Mark Smith points out the perspectivist theory of vision, which pivots on three of Aristotle's four causes, formal, material, and final, "is remarkably economical, reasonable, and coherent."[30] Although Alhacen knew that a scene imaged through an aperture is inverted, he argued that vision is about perception. This was overturned by Kepler,[31]:p.102 who modelled the eye as a water-filled glass sphere with an aperture in front of it to model the entrance pupil. He found that all the light from a single point of the scene was imaged at a single point at the back of the glass sphere. The optical chain ends on the retina at the back of the eye and the image is inverted.[nb 10]

Copernicus formulated a heliocentric model of the solar system unlike the geocentric model of Ptolemy's Almagest.

Galileo made innovative use of experiment and mathematics. However, he became persecuted after Pope Urban VIII blessed Galileo to write about the Copernican system. Galileo had used arguments from the Pope and put them in the voice of the simpleton in the work "Dialogue Concerning the Two Chief World Systems," which greatly offended him.[32]

In Northern Europe, the new technology of the printing press was widely used to publish many arguments, including some that disagreed widely with contemporary ideas of nature. René Descartes and Francis Bacon published philosophical arguments in favor of a new type of non-Aristotelian science. Descartes argued that mathematics could be used in order to study nature, as Galileo had done, and Bacon emphasized the importance of experiment over contemplation. Bacon questioned the Aristotelian concepts of formal cause and final cause, and promoted the idea that science should study the laws of "simple" natures, such as heat, rather than assuming that there is any specific nature, or "formal cause," of each complex type of thing. This new modern science began to see itself as describing "laws of nature". This updated approach to studies in nature was seen as mechanistic. Bacon also argued that science should aim for the first time at practical inventions for the improvement of all human life.

Age of Enlightenment

Isaac Newton, shown here in a 1689 portrait, made seminal contributions to classical mechanics, gravity, and optics. Newton shares credit with Gottfried Leibniz for the development of calculus.

In the 17th and 18th centuries, the project of modernity, as had been promoted by Bacon and Descartes, led to rapid scientific advance and the successful development of a new type of natural science, mathematical, methodically experimental, and deliberately innovative. Newton and Leibniz succeeded in developing a new physics, now referred to as classical mechanics, which could be confirmed by experiment and explained using mathematics. Leibniz also incorporated terms from Aristotelian physics, but now being used in a new non-teleological way, for example, "energy" and "potential" (modern versions of Aristotelian "energeia and potentia"). In the style of Bacon, he assumed that different types of things all work according to the same general laws of nature, with no special formal or final causes for each type of thing. It is during this period that the word "science" gradually became more commonly used to refer to a type of pursuit of a type of knowledge, especially knowledge of nature — coming close in meaning to the old term "natural philosophy."

19th century

Charles Darwin in 1854, by then working towards publication of On the Origin of Species

Both John Herschel and William Whewell systematized methodology: the latter coined the term scientist.[33] When Charles Darwin published On the Origin of Species he established evolution as the prevailing explanation of biological complexity. His theory of natural selection provided a natural explanation of how species originated, but this only gained wide acceptance a century later. John Dalton developed the idea of atoms. The laws of thermodynamics and the electromagnetic theory were also established in the 19th century, which raised new questions which could not easily be answered using Newton's framework. The phenomena that would allow the deconstruction of the atom were discovered in the last decade of the 19th century: the discovery of X-rays inspired the discovery of radioactivity. In the next year came the discovery of the first subatomic particle, the electron.

Combustion and chemical reactions were studied by Michael Faraday and reported in his lectures before the Royal Institution: The Chemical History of a Candle, 1861

20th century and beyond

A simulated event in the CMS detector of the Large Hadron Collider, featuring a possible appearance of the Higgs boson

Einstein's theory of relativity and the development of quantum mechanics led to the replacement of classical mechanics with a new physics which contains two parts that describe different types of events in nature.

In the first half of the century, the development of artificial fertilizer made global human population growth possible. At the same time, the structure of the atom and its nucleus was discovered, leading to the release of "atomic energy" (nuclear power). In addition, the extensive use of scientific innovation stimulated by the wars of this century led to antibiotics and increased life expectancy, revolutions in transportation (automobiles and aircraft), the development of ICBMs, a space race, and a nuclear arms race, all giving a widespread public appreciation of the importance of modern science.

Widespread use of integrated circuits in the last quarter of the 20th century combined with communications satellites led to a revolution in information technology and the rise of the global internet and mobile computing, including smartphones.