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Science

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

The scope of this article is limited to empirical sciences. For mathematical sciences, see Mathematics.

Science (from Latin scientia - knowledge) refers to a system of acquiring knowledge - based on empiricism, experimentation, and methodological naturalism - aimed at finding out the truth. The basic unit of knowledge is the theory, which is a hypothesis that is predictive. The term science also refers to the organized body of knowledge humans have gained by such research.

Most scientists feel that scientific investigation must adhere to the scientific method, a process for evaluating empirical knowledge under the working assumption of methodological materialism, which explains observable events in nature by natural causes without assuming the existence or non-existence of the supernatural. Less formally, the word science often describes any systematic field of study or the knowledge gained from it. Particular specialized studies that make use of empirical methods are often referred to as sciences as well. This article concentrates on the more specific definition.

Science as defined above is sometimes termed pure science to differentiate it from applied science, the application of research to human needs.

Fields of science may also be classified along two major lines:

• Experiment, the search for first-hand information, versus theory, the development of models to explain what is observed
• Natural science, the study of the natural phenomena, versus social science, the study of human behaviour and society

Mathematics is often referred to as a science, but the fruits of mathematical sciences, known as theorems, are obtained by logical derivations, which presume axiomatic systems rather than a combination of observation and reasoning. Many mathematical methods have fundamental utility in the empirical sciences, of which the fruits are hypotheses and theories.

The Bohr model of the atom, like many ideas in the history of science, was at first prompted by and later partially disproved by experimentation.

What is science?

There are many different conceptions of the word "science".

According to empiricism, scientific theories are objective, empirically testable, and predictive — they predict empirical results that can be checked and possibly contradicted.

In contrast, scientific realism defines science in terms of ontology: science attempts to identify phenomena and entities in the environment, their causal powers, the mechanisms through which they exercise those powers, and the sources of those powers in terms of the thing's structure or internal nature.

Even in the empiricist tradition, we must be careful to understand that "prediction" refers to the outcome of an experiment or study, rather than to literally predicting the future. For example, to say, "a paleontologist may make predictions about finding a certain type of dinosaur" is consistent with the empiricist's use of prediction. On the other hand, sciences like geology or meteorology need not be able to make accurate predictions about earthquakes or the weather to qualify as sciences. Empiricist philosopher, Karl Popper also argued that certain verification is impossible and that scientific hypotheses can only be falsified (falsification).

Positivism, a form of empiricism, advocates using science, as defined by empiricism, to govern human affairs. Because of their close affiliation, the terms "positivism" and "empiricism" are often used interchangeably. Both have been subjected to criticisms:

• W. V. Quine demonstrated the impossibility of a theory-independent observation language, so the very notion of testing theories with facts is problematic.
• Observations are always theory-laden. Thomas Kuhn argued that science always involves "paradigms," sets of (often unstated) assumptions, rules, practices, etc. and that transitions from one paradigm to another generally does not involve verification or falsification of scientific theories. Moreover, he argued that science has not proceeded historically as the steady accumulation of facts, as the empiricist model implies.

For more information, see Theories and sociology of the history of science.

Scientific method

Main article: Scientific method

The scientific method provides an objective process to find solutions to problems in a number of fields such as physics, biology, chemistry, and psychology. Many times scientists will have a preference for one outcome or another, and it is important that this preference not bias the results of their interpretation. The scientific method attempts to minimize the influence of the scientist's bias on the outcome of an experiment.

FIVE STEPS IN THE SCIENTIFIC METHOD

1. Observation: The scientific method starts with observations and descriptions of a phenomenon or group of phenomena. The scientist then raises a question about the observations. The question raised must have a concrete answer that can be obtained by performing an experiment.

2. Hypothesis: A hypothesis is an educated guess. It forms a feasible explanation for the phenomena. It will make a prediction as to the expected results if the hypothesis and other underlying assumptions and principles are true and an experiment is done to test that hypothesis. The hypothesis will many times describe a causal mechanism or a mathematical relation.

3. Testing: Experiments that are repeatable and confirmable will be developed to support the hypothesis. If results from the experiments disprove the hypothesis, then the hypothesis is ruled out. At times, the failure of an experiment may not disprove a hypothesis, but will itself have defects that need to be resolved. If the hypothesis holds up under an experiment, then the experiment becomes evidence that supports the hypothesis, but is not proof that the hypothesis is true.

4. Peer Review: Experimental tests of the predictions by several independent experimenters and properly performed experiments will either support or discredit the hypothesis.

5. Conclusion: Based on the experiments conducted, a conclusion will be reached regarding the reliability and ramifications of the hypothesis. If sufficient experimental evidence supports a hypothesis to become generally accepted in the scientific community, then it either becomes a theory or modifies an existing theory.

TERMINOLOGY RELATED TO THE SCIENTIFIC METHOD

The terms "model", "hypothesis", "theory" and "law" have different meanings in science than in 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 either well supported nor ruled out by experiment. A physical law or a law of nature is a scientific generalization based on empirical observations.

A theory is a generalization based on many observations and experiments; a well-tested, verified hypothesis that fits existing data and explains how processes or events are thought to occur. It is a basis for predicting future events or discoveries. Theories may be modified as new information is gained. This is in contrast to the common usage of the word that refers to ideas that have no firm proof or support.

To say "the apple fell" is to state a fact, whereas Newton's theory of universal gravitation is a body of ideas that explain why the apple fell. Thus a multitude of falling objects are reduced to a few concepts or abstractions interacting according to a small set of laws, allowing a scientist to make predictions about the behaviour of falling objects in general.

An especially fruitful theory that has withstood the test of time and has an overwhelming quantity of evidence supporting it is considered to be "proven" in the scientific sense. Some universally accepted models such as heliocentric theory, biological evolution, and atomic theory are so well-established that it is nearly impossible to imagine them ever being falsified. Others, such as relativity and electromagnetism have survived rigorous empirical testing without being contradicted, but it is nevertheless conceivable that they will some day be supplanted. Younger theories such as string theory may provide promising ideas, but have yet to receive the same level of scrutiny.

Scientists never claim absolute knowledge. Unlike a mathematical proof, a "proven" scientific theory is always open to falsification if new evidence is presented. Even the most basic and fundamental theories may turn out to be imperfect if new observations are inconsistent with them.

Newton's law of gravitation is a famous example of a law which was found not to hold in experiments involving motion at speeds close to the speed of light or in close proximity to strong gravitational fields. Outside those conditions, Newton's Laws remain an excellent model of motion and gravity. Because general relativity accounts for all of the phenomena that Newton's Laws do and more, general relativity is now regarded as a better theory.

Philosophy of science

Main article: Philosophy of science

The philosophy of science seeks to understand the nature and justification of scientific knowledge, and its ethical implications. It has proven difficult to provide an account of the scientific method that can serve to distinguish science from non-science.

Science is reasoned analysis of sensation upon our awareness. As such, the scientific method cannot deduce anything about the realm of reality that is beyond what is observable by existing or theoretical means. When a manifestation of our reality previously considered supernatural is understood in the terms of causes and consequences, it acquires a scientific explanation. For example, God may choose to be hidden from this reality, hence making discussion over God's existence non-scientific.

Some of the findings of science can be very counter-intuitive. Atomic theory, for example, implies that a granite boulder which appears a heavy, hard, solid, grey object 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. Quantum mechanics, particularly, examines phenomena that seem to defy our most basic postulates about causality and fundamental understanding of the world around us.

Mathematics and the scientific method

Mathematics is essential to many sciences. 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, often 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. Mathematics is most prevalent in physics, but less so in chemistry, biology, and some social sciences.

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.

Richard Feynman said "Mathematics is not real, but it feels real. Where is this place?", while Bertrand Russell's favourite definition of mathematics was "the subject in which we never know what we are talking about nor whether what we are saying is right."

Goals of science

The incredible power of science to allow the drastic manipulation of the physical world stems directly from its ability to elucidate the foundational mechanisms which underlie nature's processes. Here, an image of "artificial" bioluminescence which has been induced in a tobacco plant by the use of genetic engineering.

Despite popular impressions of science, it is not the goal of science to answer all questions. The goal of the physical sciences is to answer only those that pertain to reality. Also, science cannot possibly address nonsensical, or untestable questions, so the choice of which questions to answer becomes important. Science does not and can not produce absolute and unquestionable truth. Rather, physical science often tests hypotheses about some aspect of the physical world, and when necessary revises or replaces it in light of new observations or data.

According to empiricism, science does not make any statements about how nature actually "is"; science can only make conclusions about our observations of nature. Both scientists and the people who accept science believe, and more importantly, act as if nature actually "is" as science claims. Still, this is only a problem if we accept the empiricist notion of 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. 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. Of course, value judgements are intrinsic to science itself. For example, science values truth and knowledge.

The underlying goal or purpose of science to society and individuals is to produce useful models of reality. It has been said that it is virtually impossible to make inferences from human senses which actually describe what “is.” On the other hand, as stated, science can make predictions based on observations. These predictions often benefit society or human individuals who make use of them. For example, Newtonian physics, and in more extreme cases relativity allow us to predict anything from the effect one moving billiard ball will have on another to things like trajectories of space shuttles and satellites. The social sciences allow us to predict (with limited accuracy for now) things like economic turbulence and also to better understand human behavior and to produce useful models of society and to work more empirically with government policies. Chemistry and biology together have transformed our ability to use and predict chemical and biological reactions and scenarios. In modern times though, these segregated scientific disciplines (notably the latter two) are more often being used together in conjunction to produce more complete models and tools.

In short, science produces useful models which allow us to make often useful predictions. Science attempts to describe what is, but avoids trying to determine what is (which is for practical reasons impossible). Science is a useful tool. . . it is a growing body of understanding that allows us to contend more effectively with our surroundings and to better adapt and evolve as a social whole as well as independently.

Individualism is a tacit assumption underlying most empiricist accounts of science which treat science as if it were purely a matter of a single individual confronting nature, testing and predicting hypotheses. In fact, science is always a collective activity conducted by a scientific community. This can be demonstrated many ways, perhaps the most fundamental and trivial of which is that scientific results must be communicated with language. Thus the values of scientific communities permeate the science they produce.

Locations of science

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

Workers in corporate research laboratories also practice science, although their results are often deemed trade secrets and not published in public journals. Corporate and university scientists often cooperate, with the university scientists focusing on basic research and the corporate scientists applying their findings to a specific technology of interest to the company. Although generally this method of co-operation has benefited both the advancement of science and the corporations, it has also, in some cases lead to ethical problems, when the results arrived at in the course of research have had a negative aspect for the financing corporation. A classical example is the history of health research related to smoking.

Individuals involved in the field of science education argue that the process of science is performed by all individuals as they learn about their world.

The methods of science are also practiced in many places to achieve specific goals. For example:

• Quality control in manufacturing facilities (for example, a microbiologist in a cheese factory ensures that cultures contain the proper species of bacteria)
• Obtaining and processing crime scene evidence (forensics)
• Monitoring compliance with environmental laws
• Performing medical tests to help physicians evaluate the health of their patients
• Investigating the causes of a disaster (such as a bridge collapse or airline crash)

Science and social concerns

A basic understanding of science and technology has become indispensible for anyone living in a city or town, because technology - a product of science - has become an important part of peoples' lives. Science education aims at increasing common knowledge about science and widening social awareness. The process of learning science begins early in life for many people; school students start learning about science as soon as they acquire basic language skills, and science is always an essential part of curriculum. Science education is also a very vibrant field of study and research. Learning science requires learning its language, which often differs from colloquial language. For example, the terminology of the physical sciences is rich in mathematical jargon, and that of biological studies is rich in Latin names. The language used to communicate science is rich in words pertaining to concepts, phenomena, and processes, which are initally alien to children.

Due to the growing economic value of technology and industrial research, the economy of any modern country depends on its state of science and technology. The governments of most developed and developing countries therefore designate a significant part of their annual budget to science and technology research and communication and often have a science policy. The practice of science by scientists has undergone remarkable changes in the past few centuries. Most scientific research is currently funded by government or corporate bodies. There are also large-scale science projects - often termed as big science.

Scientific literature

Main article: Scientific literature

Science has become so pervasive in modern societies that it is generally perceived a neccessity to communicate the acheivements, news, and dreams of scientists to a wider populace. This need is fulfilled by an enourmous range of scientific literature. While scientific journals communicate and document the results of research carried out in universities and various other institutions besides new discoveries in various fields of science. Science magazines cater to the needs of a wider readership. Besides these, science books and magazines on science fiction ignite the interest of a many more people. Lately, a significant fraction of literature in science is also available on the World Wide Web; most reputed journals and newsmagazines have their own websites. Also, a growing number of people are being attracted towards the vocation of science popularization and science journalism.

Fields of science

Natural sciences

See also: #Social sciences