Science


 * For the scientific journal named Science, see Science (journal).

Science is both a process of gaining knowledge, and the organized body of knowledge gained by this process. The scientific process is the systematic acquisition of new knowledge about a system. This systematic acquisition is generally the scientific method, and the system is generally nature. Science is also the scientific knowledge that has been systematically acquired by this scientific process.

Some of the findings of science can be very counter-intuitive. Atomic theory, for example, implies that a granite boulder which appears as heavy, hard, solid, grey, etc. is actually a combination of subatomic particles with none of these properties, moving very rapidly in an area consisting mostly of empty space. Many of humanity's preconceived notions about the workings of the universe have been challenged by new scientific discoveries.

Scientific models, theories and laws
Main article: scientific method

The terms "hypothesis", "model", "theory", and "law" have a different use in science to colloquial speech. Scientists use the term model to mean a description of something, specifically one which can be used to make predictions which can be tested by experiment or observation. A hypothesis is a contention that has not (yet) been well supported nor ruled out by experiment. A physical law or a law of nature is a scientific generalization based on empirical observations.

Most non-scientists are unaware that what scientists call "theories" are what most people call "facts". The general public uses the word theory to refer to ideas that have no firm proof or support; in contrast, scientists usually use this word to refer only to ideas that have repeatedly withstood test. Thus, when scientists refer to the theories of biological evolution, electromagnetism, and relativity, they are referring to ideas that have survived considerable experimental testing. But there are exceptions, such as string theory, which seems to be a promising model but as yet has no empirical evidence to give it precedence over competing models.

Especially fruitful theories that have withstood the test of time are considered to be "proven" in the scientific sense – that it is true and factual but of course can still be falsified. This includes many theories, such as universally accepted ones such as heliocentric theory and controversial ones such as evolution, which are backed by many observations and experimental data. Theories are always open to revision if new evidence is provided or directly contradicts predictions or other evidence. As scientists do not claim absolute knowledge, even the most basic and fundamental theories may turn out to be incorrect if new data and observations contradict older ones.

Newton's law of gravitation is a famous example of a law falsified by experiments regarding motions at high speeds and in close proximity to strong gravitational fields. Outside of those conditions, Newton's Laws remain excellent accounts of motion and gravity. Because general relativity accounts for all of the phenomena that Newton's Laws do, and more, general relativity is currently regarded as our best account of gravitation.

Philosophy of science
Science's effectiveness has made it a subject of much philosophical speculation. The philosophy of science seeks to understand the nature and justification of scientific knowledge, and its ethical implications. It has proved remarkably difficult to provide an account of the scientific method that can serve to distinguish science from non-science.

Mathematics and the scientific method
Mathematics is essential to science. The most important function of mathematics in science is the role it plays in the expression of scientific models. Observing and collecting measurements, as well as hypothesizing and predicting, typically require mathematical models and extensive use of mathematics. Mathematical branches most often used in science include calculus and statistics, although virtually every branch of mathematics has applications, even "pure" areas such as number theory and topology.

Some thinkers see mathematicians as scientists, regarding physical experiments as inessential or mathematical proofs as equivalent to experiments. Others do not see mathematics as a science, since it does not require experimental test of its theories and hypotheses. In either case, the fact that mathematics is such a useful tool in describing the universe is a central issue in the philosophy of mathematics.

See: Eugene Wigner The Unreasonable Effectiveness of Mathematics.

Richard Feynman said "Mathematics is not real, but it feels real. Where is this place?"

Bertrand Russell's favourite definition of mathematics: "the subject in which we never know what we are talking about nor whether what we are saying is right."

Goals of science
Despite popular impressions of science, it is not the goal of science to answer all questions, only those that pertain to physical reality (measurable empirical experience). Also, science cannot possibly address all possible questions, so the choice of which questions to answer becomes important. Science does not and can not produce absolute and unquestionable truth. Rather, science consistently tests the currently best hypothesis about some aspect of the physical world, and when necessary revises or replaces it in light of new observations or data.

Science does not make any statements about how nature actually "is"; science can only make conclusions about our observations of nature. The developments of quantum mechanics in the early 20th century showed that observations are not independent of interactions, and the implications of wave-particle duality have challenged the traditional notion of "objectivity" in science.

Science is not a source of subjective value judgements, though it can certainly speak to matters of ethics and public policy by pointing to the likely consequences of actions. However, science can't tell us which of those consequences to desire or which is 'best'. What one projects from the currently most reasonable scientific hypothesis onto other realms of interest is not a scientific issue, and the scientific method offers no assistance for those who wish to do so. Scientific justification (or refutation) for many things is, nevertheless, often claimed.

Locations of science
Science is practiced in university and other scientific institutes as well as in the field; as such it is a solid vocation in academia, but has also been practiced by amateurs, who typically engage in the observational part of science.

Some workers in corporate research laboratories also practice the methods of science and eventually become renowned enough in their fields to also work in academia. Conversely, some academics become well-known enough to consult to industry by applying their findings in some technology.

Natural sciences

 * Physics
 * Acoustics
 * Astrodynamics
 * Astronomy
 * Astrophysics
 * Atomic, Molecular, and Optical physics
 * Biophysics
 * Computational physics
 * Condensed matter physics
 * Cryogenics
 * Dynamics
 * Electronics
 * Engineering
 * Fluid dynamics
 * Materials physics
 * Mathematical physics
 * Mechanics
 * Nuclear physics
 * Optics
 * Particle physics (or High Energy Physics)
 * Plasma physics
 * Polymer physics
 * Vehicle dynamics


 * Chemistry
 * Analytical chemistry
 * Biochemistry
 * Computational chemistry
 * Electrochemistry
 * Inorganic chemistry
 * Materials science
 * Organic chemistry
 * Physical chemistry
 * Quantum chemistry
 * Spectroscopy
 * Stereochemistry
 * Thermochemistry


 * Earth Sciences
 * Geodesy
 * Geography
 * Geology
 * Meteorology
 * Oceanography
 * Limnology
 * Seismology


 * Biology
 * Agricultural science
 * Anatomy
 * Anthropology
 * Astrobiology
 * Biochemistry
 * Bioinformatics
 * Biophysics
 * Botany
 * Cell biology
 * Cladistics
 * Cytology
 * Developmental biology
 * Ecology
 * Entomology
 * Epidemiology
 * Evolution (Evolutionary biology)
 * Evolutionary developmental biology ("Evo-devo" or Evolution of Development)
 * Freshwater Biology
 * Genetics (Population genetics, Genomics, Proteomics)
 * Health Science
 * Dentistry
 * Medicine
 * Pharmacology
 * Toxicology
 * Veterinary medicine
 * Histology
 * Immunology
 * Marine biology
 * Microbiology
 * Molecular Biology
 * Morphology
 * Neuroscience
 * Oncology (the study of cancer)
 * Ontogeny
 * Paleontology
 * Pathology
 * Phycology (Algology)
 * Phylogeny
 * Physiology
 * Structural biology
 * Taxonomy
 * Toxicology
 * Virology
 * Zoology

Social sciences

 * Anthropology
 * Archaeology
 * Economics
 * Linguistics
 * Etymology
 * Psychology
 * Sociology
 * Education
 * Social Work

Etymology
The word science comes from the Latin word, scientia, which means knowledge.

Until the Enlightenment, the word "science" (or its Latin cognate) meant any systematic or exact, recorded knowledge. "Science" therefore had the same sort of very broad meaning that "philosophy" had at that time.

There was a distinction between, for example, "natural science" and "moral science," which latter included what we now call philosophy, and this mirrored a distinction between "natural philosophy" and "moral philosophy." More recently, "science" has come to be restricted to what used to be called "natural science" or "natural philosophy." Natural science can be further broken down into physical science and biological science. Social science is often included in the field of science as well.

Fields of study are often distinguished in terms of "hard sciences" and "soft sciences," and these terms (at times considered derogatory) are often synonymous with the terms natural and social science (respectively). Physics, chemistry, biology and geology are all forms of "hard sciences". Studies of anthropology, history, psychology, and sociology are sometimes called "soft sciences." Proponents of this division use the arguments that the "soft sciences" do not use the scientific method, admit anecdotal evidence, or are not mathematical, all adding up to a "lack of rigor" in their methods. Opponents of the division in the sciences counter that the "social sciences" often make systematic statistical studies in strictly controlled environments, or that these conditions are not adhered to by the natural sciences either (for example, behavioral biology relies upon fieldwork in uncontrolled environments, astronomy cannot design experiments, only observe limited conditions). Opponents of the division also point out that each of the current "hard sciences" suffered a similar "lack of rigor" in its own infancy.

The term "science" is sometimes pressed into service for new and interdisciplinary fields that make use of scientific methods at least in part, and which in any case aspire to be systematic and careful explorations of their subjects, including computer science, library and information science, and environmental science. Mathematics and computer science reside under "Q" in the Library of Congress classification, along with all else we now call science.

Related topics

 * Organization and practice of science: International Council of Science (ICSU).
 * For an understanding of how these fields came to be: History of Science and Technology.
 * See also scientists for catalogs of people active in each of these fields.

Resources

 * Ethics in Science
 * Current Events in Science Magazine
 * United States Science Initiative
 * Simple Introduction to Science

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