The scale of the Universe mapped to branches of science and the hierarchy of the sciences.
The branches of science, also referred to as sciences, "scientific fields", or "scientific disciplines," are commonly divided into three major groups:
- Formal sciences: the study of mathematics, logic, and statistics, which use an a priori, as opposed to empirical, methodology.
- Natural sciences: the study of natural phenomena (including cosmological, geological, physical, chemical, and biological factors of the universe). Natural science can be divided into two main branches: physical science and life science (or biological science).
- Social sciences: the study of human behavior and societies.
Natural and social sciences are empirical
sciences, meaning that the knowledge must be based on observable
phenomena and must be capable of being verified by other researchers
working under the same conditions. This verifiability may well vary even within a scientific discipline.
Natural, social, and formal science make up the fundamental sciences, which form the basis of interdisciplinary and applied sciences such as engineering and medicine.
Specialized scientific disciplines that exist in multiple categories
may include parts of other scientific disciplines but often possess
their own terminologies and expertises.
Formal sciences
The formal sciences are the branches of science that are concerned with formal systems, such as logic, mathematics, theoretical computer science, information theory, systems theory, decision theory, statistics, and theoretical linguistics.
Unlike other sciences, the formal sciences are not concerned with the validity of theories based on observations in the real world (empirical knowledge), but rather with the properties of formal systems based on definitions and rules. Methods of the formal sciences are, however, essential to the construction and testing of scientific models dealing with observable reality, and major advances in formal sciences have often enabled major advances in the empirical sciences.
Decision theory
Decision theory in economics, psychology, philosophy,
mathematics, and statistics is concerned with identifying the values,
uncertainties and other issues relevant in a given decision, its
rationality, and the resulting optimal decision. It is very closely
related to the field of game law.
Logic
Logic (from the Greek λογική logikē) is the formal systematic study of the principles of valid inference and correct reasoning. Logic is used in most intellectual activities, but is studied primarily in the disciplines of philosophy, mathematics, semantics, and computer science. Logic examines general forms which arguments may take, which forms are valid, and which are fallacies. In philosophy, the study of logic figures in most major areas: epistemology, ethics, metaphysics. In mathematics and computer science, it is the study of valid inferences within some formal language.
Logic is also studied in argumentation theory.
Mathematics
Mathematics, first of all known as The Science of numbers which is classified in Arithmetic and Algebra, is classified as a formal science,
has both similarities and differences with the empirical sciences (the
natural and social sciences). It is similar to empirical sciences in
that it involves an objective, careful and systematic study of an area
of knowledge; it is different because of its method of verifying its
knowledge, using a priori rather than empirical methods.
Statistics
Statistics is the study of the collection, organization, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments.
A statistician
is someone who is particularly well versed in the ways of thinking
necessary for the successful application of statistical analysis. Such
people have often gained this experience through working in any of a wide number of fields. There is also a discipline called mathematical statistics, which is concerned with the theoretical basis of the subject.
The word statistics, when referring to the scientific discipline, is singular, as in "Statistics is an art." This should not be confused with the word statistic, referring to a quantity (such as mean or median) calculated from a set of data, whose plural is statistics ("this statistic seems wrong" or "these statistics are misleading").
Systems theory
Systems theory is the interdisciplinary study of systems
in general, with the goal of elucidating principles that can be applied
to all types of systems in all fields of research. The term does not
yet have a well-established, precise meaning, but systems theory can
reasonably be considered a specialization of systems thinking and a generalization of systems science. The term originates from Ludwig von Bertalanffy's General System Theory (GS) and is used in later efforts in other fields, such as the action theory of Alcott Parsons and the system-theory of Nickolas McLuhan.
In this context the word systems is used to refer specifically to self-regulating systems, i.e. that are self-correcting through feedback.
Self-regulating systems are found in nature, including the
physiological systems of our body, in local and global ecosystems, and
in climate.
Theoretical computer science
Theoretical computer science (TCS) is a division or subset of general computer science and focuses on more abstract or mathematical aspects of computing.
These divisions and subsets include analysis of algorithms and formal semantics of programming languages.
Technically, there are hundreds of divisions and subsets besides these
two. Each of the multiple parts have their own individual personal
leaders (of popularity) and there are many associations and professional
social groups and publications of distinction.
Natural/Pure Science
Natural science is a branch of science that seeks to elucidate the rules that govern the natural world by applying an empirical and scientific method to the study of the universe. The term natural sciences is used to distinguish it from the social sciences, which apply the scientific method to study human behavior and social patterns; the humanities, which use a critical, or analytical approach to the study of the human condition; and the formal sciences.
Physical science
Physical science is an encompassing term for the branches of natural
science and science that study non-living systems, in contrast to the
life sciences. However, the term "physical" creates an unintended,
somewhat arbitrary distinction, since many branches of physical science
also study biological phenomena. There is a difference between physical
science and physics.
Physics
Physics (from Ancient Greek: φύσις, romanized: physis, lit. 'nature') is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.
Physics is one of the oldest academic disciplines, perhaps the oldest through its inclusion of astronomy. Over the last two millennia, physics was a part of natural philosophy along with chemistry, certain branches of mathematics, and biology, but during the Scientific Revolution in the 16th century, the natural sciences emerged as unique research programs in their own right. Certain research areas are interdisciplinary, such as biophysics and quantum chemistry, which means that the boundaries of physics are not rigidly defined. In the nineteenth and twentieth centuries physicalism emerged as a major unifying feature of the philosophy of science as physics provides fundamental explanations for every observed natural phenomenon.
New ideas in physics often explain the fundamental mechanisms of other
sciences, while opening to new research areas in mathematics and
philosophy.
Chemistry
Chemistry (the etymology of the word has been much disputed) is the science of matter and the changes it undergoes. The science of matter is also addressed by physics,
but while physics takes a more general and fundamental approach,
chemistry is more specialized, being concerned by the composition,
behavior (or reaction), structure, and properties of matter, as well as the changes it undergoes during chemical reactions. It is a physical science which studies various substances, atoms, molecules, and matter (especially carbon based); biochemistry, the study of substances found in biological organisms; physical chemistry, the study of chemical processes using physical concepts such as thermodynamics and quantum mechanics; and analytical chemistry, the analysis of material samples to gain an understanding of their chemical composition and structure. Many more specialized disciplines have emerged in recent years, e.g. neurochemistry the chemical study of the nervous system (see subdisciplines).
Earth science
Earth science (also known as geoscience, the geosciences or the Earth sciences) is an all-embracing term for the sciences related to the planet Earth. It is arguably a special case in planetary science, the Earth being the only known life-bearing planet. There are both reductionist and holistic
approaches to Earth sciences. The formal discipline of Earth sciences
may include the study of the atmosphere, hydrosphere, oceans and
biosphere, as well as the solid earth. Typically Earth scientists will
use tools from physics, chemistry, biology, geography, chronology and mathematics to build a quantitative understanding of how the Earth system works, and how it evolved to its current state.
Ecology
Ecology (from Greek: οἶκος, "house"; -λογία, "study of") is the scientific study of the relationships that living organisms have with each other and with their abiotic environment. Topics of interest to ecologists include the composition, distribution, amount (biomass), number, and changing states of organisms within and among ecosystems.
Oceanography
Oceanography, or marine biology, is the branch of Earth science that studies ocean. It covers a wide range of topics, including marine organisms and ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics; plate tectonics and the geology of the sea floor; and fluxes
of various chemical substances and physical properties within the ocean
and across its boundaries. These diverse topics reflect multiple
disciplines that oceanographers blend to further knowledge of the world
ocean and understanding of processes within it: biology, chemistry, geology, meteorology, and physics as well as geography.
Geology
Geology (from the Greek γῆ, gê, "earth" and λόγος, logos, "study") is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change.
Meteorology
Meteorology is the interdisciplinary scientific study of the atmosphere.
Studies in the field stretch back millennia, though significant
progress in meteorology did not occur until the 17th century. The 19th
century saw breakthroughs occur after observing networks developed
across several countries. After the development of the computer in the
latter half of the 20th century, breakthroughs in weather forecasting were achieved.
Space Science or Astronomy
Space science or Astronomy is the study of everything in outer space. This has sometimes been called astronomy,
but recently astronomy has come to be regarded as a division of broader
space science, which has grown to include other related fields, such as studying issues related to space travel and space exploration (including space medicine), space archaeology and science performed in outer space.
Science of living things
The science of living things comprises the branches of science
that involve the scientific study of living organisms, like plants,
animals, and human beings. However, the study of behavior of organisms,
such as practiced in ethology and psychology, is only included in as
much as it involves a clearly biological aspect. While biology remains
the centerpiece of the science of living things, technological advances
in molecular biology and biotechnology have led to a burgeoning of
specializations and new, often interdisciplinary, fields.
Biology
Biology is the branch of natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines.
Zoology
Zoology, occasionally spelled zoölogy, is the branch of science that
relates to the animal kingdom, including the structure, embryology,
evolution, classification, habits, and distribution of all animals, both
living and extinct. The term is derived from Ancient Greek ζῷον (zōon,
"animal") + λόγος (logos, "knowledge"). Some branches of zoology
include: anthrozoology, arachnology, archaeozoology, cetology, embryology, entomology, helminthology, herpetology, histology, ichthyology, malacology, mammalogy, morphology, nematology, ornithology, palaeozoology, pathology, primatology, protozoology, taxonomy, and zoogeography.
Human biology
Human biology is an interdisciplinary academic field of biology,
biological anthropology, nutrition and medicine which focuses on humans;
it is closely related to primate biology, and a number of other fields.
Some branches of biology include: microbiology, anatomy, neurology and neuroscience, immunology, genetics, physiology, pathology, biophysics, biolinguistics, and ophthalmology.
Botany
Botany, plant science, or plant biology is a branch of biology that
involves the scientific study of plant life. Botany covers a wide range
of scientific disciplines including structure, growth, reproduction,
metabolism, development, diseases, chemical properties, and evolutionary
relationships among taxonomic groups. Botany began with early human
efforts to identify edible, medicinal and poisonous plants, making it
one of the oldest sciences. Today botanists study over 550,000 species
of living organisms.
The term "botany" comes from Greek βοτάνη, meaning "pasture, grass,
fodder", perhaps via the idea of a livestock keeper needing to know
which plants are safe for livestock to eat.
Social sciences
The social sciences are the fields of scholarship that study society. "Social science" is commonly used as an umbrella term for empirical fields outside of the natural sciences. These include: anthropology, archaeology, criminology, economics, linguistics, international relations, political science (aka government), public health, sociology, some branches of psychology (results of which can not be replicated or validated easily - e.g. social psychology), and certain aspects of business administration, communication, education, geography, history, and law.
Applied sciences
Applied science is the application of scientific knowledge
transferred into a physical environment. Examples include testing a
theoretical model through the use of formal science or solving a
practical problem through the use of natural science.
Applied science differs from fundamental science,
which seeks to describe the most basic objects and forces, having less
emphasis on practical applications. Applied science can be like
biological science and physical science.
Example fields of applied science include
Fields of engineering are closely related to applied sciences. Applied science is important for technology development. Its use in industrial settings is usually referred to as research and development (R&D).
