
Observation in the
natural sciences
Natural science or empirical science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer ...
is an act or instance of
noticing or perceiving and the acquisition of
information
Information is an Abstraction, abstract concept that refers to something which has the power Communication, to inform. At the most fundamental level, it pertains to the Interpretation (philosophy), interpretation (perhaps Interpretation (log ...
from a
primary source
In the study of history as an academic discipline, a primary source (also called an original source) is an Artifact (archaeology), artifact, document, diary, manuscript, autobiography, recording, or any other source of information that was cre ...
. In living beings, observation employs the
sense
A sense is a biological system used by an organism for sensation, the process of gathering information about the surroundings through the detection of Stimulus (physiology), stimuli. Although, in some cultures, five human senses were traditio ...
s. In
science
Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...
, observation can also involve the
perception
Perception () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous syste ...
and recording of
data
Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted for ...
via the use of
scientific instrument
A scientific instrument is a device or tool used for scientific purposes, including the study of both natural phenomena and theoretical research.
History
Historically, the definition of a scientific instrument has varied, based on usage, laws, an ...
s. The term may also refer to any data collected during the scientific activity. Observations can be
qualitative, that is, the absence or presence of a property is noted and the observed phenomenon described, or
quantitative
Quantitative may refer to:
* Quantitative research, scientific investigation of quantitative properties
* Quantitative analysis (disambiguation)
* Quantitative verse, a metrical system in poetry
* Statistics, also known as quantitative analysis
...
if a numerical value is attached to the observed
phenomenon
A phenomenon ( phenomena), sometimes spelled phaenomenon, is an observable Event (philosophy), event. The term came into its modern Philosophy, philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be ...
by counting or measuring.
Science
The
scientific method
The scientific method is an Empirical evidence, empirical method for acquiring knowledge that has been referred to while doing science since at least the 17th century. Historically, it was developed through the centuries from the ancient and ...
requires observations of
natural phenomena
Nature is an inherent character or constitution, particularly of the ecosphere or the universe as a whole. In this general sense nature refers to the laws, elements and phenomena of the physical world, including life. Although humans are part ...
to formulate and test
hypotheses
A hypothesis (: hypotheses) is a proposed explanation for a phenomenon. A scientific method, scientific hypothesis must be based on observations and make a testable and reproducible prediction about reality, in a process beginning with an educ ...
.
It consists of the following steps:
# Ask a
question
A question is an utterance which serves as a request for information. Questions are sometimes distinguished from interrogatives, which are the grammar, grammatical forms, typically used to express them. Rhetorical questions, for instance, are i ...
about a
phenomenon
A phenomenon ( phenomena), sometimes spelled phaenomenon, is an observable Event (philosophy), event. The term came into its modern Philosophy, philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be ...
# Make observations of the phenomenon
# Formulate a
hypothesis
A hypothesis (: hypotheses) is a proposed explanation for a phenomenon. A scientific hypothesis must be based on observations and make a testable and reproducible prediction about reality, in a process beginning with an educated guess o ...
that tentatively answers the question
#
Predict logical, observable
consequences of the hypothesis that have not yet been investigated
# Test the hypothesis' predictions by an
experiment
An experiment is a procedure carried out to support or refute a hypothesis, or determine the efficacy or likelihood of something previously untried. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs whe ...
,
observational study
In fields such as epidemiology, social sciences, psychology and statistics, an observational study draws inferences from a sample (statistics), sample to a statistical population, population where the dependent and independent variables, independ ...
,
field study, or
simulation
A simulation is an imitative representation of a process or system that could exist in the real world. In this broad sense, simulation can often be used interchangeably with model. Sometimes a clear distinction between the two terms is made, in ...
# Draw a
conclusion from
data
Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted for ...
gathered in the experiment, or revise the hypothesis or form a new one, and
repeat the process
# Write a
descriptive method of observation and the
result
A result (also called upshot) is the outcome or consequence of a sequence of actions or events. Possible results include gain, injury, value, and victory. Some types of results include the outcome of an action, the final value of a calculation ...
s or conclusions reached
# Have peers with experience researching the same phenomenon
evaluate
In common usage, evaluation is a systematic determination and assessment of a subject's merit, worth and significance, using criteria governed by a set of standards. It can assist an organization, program, design, project or any other intervention ...
the results
Observations play a role in the second and fifth steps of the scientific method. However, the need for
reproducibility
Reproducibility, closely related to replicability and repeatability, is a major principle underpinning the scientific method. For the findings of a study to be reproducible means that results obtained by an experiment or an observational study or ...
requires that observations by different observers can be comparable. Human
sense
A sense is a biological system used by an organism for sensation, the process of gathering information about the surroundings through the detection of Stimulus (physiology), stimuli. Although, in some cultures, five human senses were traditio ...
impressions are
subjective and
qualitative, making them difficult to record or compare. The use of
measurement
Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events.
In other words, measurement is a process of determining how large or small a physical quantity is as compared to ...
was developed to allow the recording and comparison of observations made at different times and places, by different people. The measurement consists of using observation to compare the phenomenon being observed to a
standard unit. The standard unit can be an artifact, process, or definition that can be duplicated or shared by all observers. In measurement, the number of standard units that is equal to the observation is counted. Measurement reduces an observation to a number that can be recorded, and two observations that result in the same number are equal within the
resolution of the process.
Human senses are limited and subject to errors in perception, such as
optical illusion
In visual perception, an optical illusion (also called a visual illusion) is an illusion caused by the visual system and characterized by a visual perception, percept that arguably appears to differ from reality. Illusions come in a wide varie ...
s.
Scientific instrument
A scientific instrument is a device or tool used for scientific purposes, including the study of both natural phenomena and theoretical research.
History
Historically, the definition of a scientific instrument has varied, based on usage, laws, an ...
s were developed to aid human abilities of observation, such as
weighing scale
A scale or balance is a device used to measure weight or mass. These are also known as mass scales, weight scales, mass balances, massometers, and weight balances.
The traditional scale consists of two plates or bowls suspended at equal d ...
s,
clock
A clock or chronometer is a device that measures and displays time. The clock is one of the oldest Invention, human inventions, meeting the need to measure intervals of time shorter than the natural units such as the day, the lunar month, a ...
s,
telescope
A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using len ...
s,
microscope
A microscope () is a laboratory equipment, laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic ...
s,
thermometer
A thermometer is a device that measures temperature (the hotness or coldness of an object) or temperature gradient (the rates of change of temperature in space). A thermometer has two important elements: (1) a temperature sensor (e.g. the bulb ...
s,
camera
A camera is an instrument used to capture and store images and videos, either digitally via an electronic image sensor, or chemically via a light-sensitive material such as photographic film. As a pivotal technology in the fields of photograp ...
s, and
tape recorder
An audio tape recorder, also known as a tape deck, tape player or tape machine or simply a tape recorder, is a sound recording and reproduction device that records and plays back sounds usually using magnetic tape for storage. In its present ...
s, and also translate into perceptible form events that are unobservable by the senses, such as
indicator dyes,
voltmeter
A voltmeter is an instrument used for measuring electric potential difference between two points in an electric circuit. It is connected in parallel. It usually has a high resistance so that it takes negligible current from the circuit.
A ...
s,
spectrometer
A spectrometer () is a scientific instrument used to separate and measure Spectrum, spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomeno ...
s,
infrared camera
Infrared thermography (IRT), thermal video or thermal imaging, is a process where a thermal camera captures and creates an image of an object by using infrared radiation emitted from the object in a process, which are examples of infrared im ...
s,
oscilloscope
An oscilloscope (formerly known as an oscillograph, informally scope or O-scope) is a type of electronic test instrument that graphically displays varying voltages of one or more signals as a function of time. Their main purpose is capturing i ...
s,
interferometer
Interferometry is a technique which uses the '' interference'' of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber opt ...
s,
Geiger counter
A Geiger counter (, ; also known as a Geiger–Müller counter or G-M counter) is an electronic instrument for detecting and measuring ionizing radiation with the use of a Geiger–Müller tube. It is widely used in applications such as radiat ...
s, and
radio receiver
In radio communications, a radio receiver, also known as a receiver, a wireless, or simply a radio, is an electronic device that receives radio waves and converts the information carried by them to a usable form. It is used with an antenna. ...
s.
One problem encountered throughout scientific fields is that the observation may affect the process being observed, resulting in a different outcome than if the process were unobserved. This is called the ''
observer effect''. For example, it is not normally possible to check the air pressure in an automobile tire without letting out some of the air, thereby changing the pressure. However, in most fields of science, it is possible to reduce the effects of observation to insignificance by using better instruments.
Considered as a physical process itself, all forms of observation (human or instrumental) involve amplification and are thus thermodynamically
irreversible processes, increasing
entropy
Entropy is a scientific concept, most commonly associated with states of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the micros ...
.
Paradoxes
In some specific fields of science, the results of observation differ depending on factors that are not important in everyday observation. These are usually illustrated with apparent "
paradox
A paradox is a logically self-contradictory statement or a statement that runs contrary to one's expectation. It is a statement that, despite apparently valid reasoning from true or apparently true premises, leads to a seemingly self-contradictor ...
es" in which an event appears different when observed from two different points of view, seeming to violate "common sense".
* Relativity: In
relativistic physics
In physics, relativistic mechanics refers to mechanics compatible with special relativity (SR) and general relativity (GR). It provides a non- quantum mechanical description of a system of particles, or of a fluid, in cases where the velocities o ...
which deals with velocities close to the
speed of light
The speed of light in vacuum, commonly denoted , is a universal physical constant exactly equal to ). It is exact because, by international agreement, a metre is defined as the length of the path travelled by light in vacuum during a time i ...
, it is found that different observers may observe different values for the length, time rates, mass, and many other properties of an object, depending on the observer's velocity relative to the object. For example, in the
twin paradox
In physics, the twin paradox is a thought experiment in special relativity involving twins, one of whom takes a space voyage at relativistic speeds and returns home to find that the twin who remained on Earth has aged more. This result appear ...
one twin goes on a trip near the speed of light and comes home younger than the twin who stayed at home. This is not a paradox: time passes at a slower rate when measured from a frame moving concerning the object. In relativistic physics, an observation must always be qualified by specifying the state of motion of the observer, its
reference frame
In physics and astronomy, a frame of reference (or reference frame) is an abstract coordinate system, whose origin, orientation, and scale have been specified in physical space. It is based on a set of reference points, defined as geometric ...
.
* Quantum mechanics: In
quantum mechanics
Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is ...
, which deals with the behavior of very small objects, it is not possible to
observe a system without changing the system, and the "observer" must be considered part of the
system
A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its open system (systems theory), environment, is described by its boundaries, str ...
being observed. In isolation, quantum objects are represented by a
wave function
In quantum physics, a wave function (or wavefunction) is a mathematical description of the quantum state of an isolated quantum system. The most common symbols for a wave function are the Greek letters and (lower-case and capital psi (letter) ...
which often exists in a
superposition
In mathematics, a linear combination or superposition is an expression constructed from a set of terms by multiplying each term by a constant and adding the results (e.g. a linear combination of ''x'' and ''y'' would be any expression of the form ...
or mixture of different
states
State most commonly refers to:
* State (polity), a centralized political organization that regulates law and society within a territory
**Sovereign state, a sovereign polity in international law, commonly referred to as a country
**Nation state, a ...
. However, when an observation is made to determine the actual location or state of the object, it always finds the object in a single state, not a "mixture". The interaction of the observation process appears to "
collapse" the wave function into a single state. So any interaction between an isolated wave function and the external world that results in this wave function collapse is called an ''observation'' or ''measurement'', whether or not it is part of a deliberate observation process.
Biases
The human senses do not function like a video
camcorder
A camcorder is a self-contained portable electronic device with video and recording as its primary function. It is typically equipped with an articulating screen mounted on the left side, a belt to facilitate holding on the right side, hot-sw ...
, impartially recording all observations.
Human perception occurs by a complex, unconscious process of
abstraction
Abstraction is a process where general rules and concepts are derived from the use and classifying of specific examples, literal (reality, real or Abstract and concrete, concrete) signifiers, first principles, or other methods.
"An abstraction" ...
, in which certain details of the incoming sense data are noticed and remembered, and the rest is forgotten. What is kept and what is thrown away depends on an internal model or representation of the world, called by psychologists a ''
schema
Schema may refer to:
Science and technology
* SCHEMA (bioinformatics), an algorithm used in protein engineering
* Schema (genetic algorithms), a set of programs or bit strings that have some genotypic similarity
* Schema.org, a web markup vocab ...
'', that is built up over our entire lives. The data is fitted into this schema. Later, when events are remembered, memory gaps may even be filled by "plausible" data the mind makes up to fit the model; this is called ''
reconstructive memory
Reconstructive memory is a theory of memory recall, in which the act of remembering is influenced by various other cognitive processes including perception, imagination, motivation, semantic memory and beliefs, amongst others. People view their m ...
''. How much attention the various perceived data are given depends on an internal value system, which judges how important it is to the individual. Thus, two people can view the same event and come away with very different perceptions of it, even disagreeing about simple facts. This is why
eyewitness testimony
Eyewitness testimony is the account a bystander or victim gives in the courtroom, describing what that person observed that occurred during the specific incident under investigation. Ideally this recollection of events is detailed; however, this is ...
is notoriously unreliable.
Correct scientific technique emphasizes careful recording of observations, separating experimental observations from the conclusions drawn from them, and techniques such as
blind or
double blind experiments, to minimize observational bias.
Several of the more important ways observations can be affected by human psychology are given below.
Streetlight effect
*
Confirmation bias
Human observations are biased toward confirming the observer's conscious and unconscious expectations and view of the world; we "''see what we expect to see''".
In psychology, this is called
confirmation bias
Confirmation bias (also confirmatory bias, myside bias, or congeniality bias) is the tendency to search for, interpret, favor and recall information in a way that confirms or supports one's prior beliefs or Value (ethics and social sciences), val ...
.
Since the object of scientific research is the
discovery
Discovery may refer to:
* Discovery (observation), observing or finding something unknown
* Discovery (fiction), a character's learning something unknown
* Discovery (law), a process in courts of law relating to evidence
Discovery, The Discovery ...
of new phenomena, this bias can and has caused new discoveries to be overlooked; one example is the discovery of
x-ray
An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...
s. It can also result in erroneous scientific support for widely held cultural myths, on the other hand, as in the
scientific racism
Scientific racism, sometimes termed biological racism, is the pseudoscience, pseudoscientific belief that the Human, human species is divided into biologically distinct taxa called "race (human categorization), races", and that empirical evi ...
that supported ideas of racial superiority in the early 20th century.
Processing bias
Modern scientific instruments can extensively process "observations" before they are presented to the human senses, and particularly with computerized instruments, there is sometimes a question as to where in the data processing chain "observing" ends and "drawing conclusions" begins. This has recently become an issue with
digitally enhanced images published as experimental data in
papers in
scientific journal
In academic publishing, a scientific journal is a periodical publication designed to further the progress of science by disseminating new research findings to the scientific community. These journals serve as a platform for researchers, schola ...
s. The images are enhanced to bring out features that the researcher wants to emphasize, but this also has the effect of supporting the researcher's conclusions. This is a form of bias that is difficult to quantify. Some
scientific journal
In academic publishing, a scientific journal is a periodical publication designed to further the progress of science by disseminating new research findings to the scientific community. These journals serve as a platform for researchers, schola ...
s have begun to set detailed standards for what types of
image processing
An image or picture is a visual representation. An image can be two-dimensional, such as a drawing, painting, or photograph, or three-dimensional, such as a carving or sculpture. Images may be displayed through other media, including a pr ...
are allowed in research results. Computerized instruments often keep a copy of the "raw data" from sensors before processing, which is the ultimate defense against processing bias, and similarly, scientific standards require preservation of the original unenhanced "raw" versions of images used as research data.
See also
*
Deixis
In linguistics, deixis () is the use of words or phrases to refer to a particular time (e.g. ''then''), place (e.g. ''here''), or person (e.g. ''you'') relative to the Context (language use), context of the utterance. Deixis exists in all known na ...
*
Extrospection
*
Introspection
Introspection is the examination of one's own conscious thoughts and feelings. In psychology, the process of introspection relies on the observation of one's mental state, while in a spiritual context it may refer to the examination of one's s ...
*
List of cognitive biases
Cognitive biases are systematic patterns of deviation from norm and/or rationality in judgment. They are often studied in psychology, sociology and behavioral economics.
Although the reality of most of these biases is confirmed by reproducible ...
*
Metaphysics of presence
Metaphysics of presence () is a view held by Martin Heidegger in ''Being and Time'' that holds the entire history of Western philosophy
Western philosophy refers to the Philosophy, philosophical thought, traditions and works of the Western wor ...
*
Naturalistic observation
Naturalistic observation, sometimes referred to as fieldwork, is a research methodology in numerous fields of science including ethology, anthropology, linguistics, the social sciences, and psychology, in which data are collected as they occur in ...
*
Observation unit
*
Observational astronomy
Observational astronomy is a division of astronomy that is concerned with recording data about the observable universe, in contrast with theoretical astronomy, which is mainly concerned with calculating the measurable implications of physical ...
*
Observational error
Observational error (or measurement error) is the difference between a measured value of a quantity and its unknown true value.Dodge, Y. (2003) ''The Oxford Dictionary of Statistical Terms'', OUP. Such errors are inherent in the measurement ...
*
Observational learning
Observational learning is learning that occurs through observing the behavior of others. It is a form of Social learning theory, social learning which takes various forms, based on various processes. In humans, this form of learning seems to not n ...
*
Observational study
In fields such as epidemiology, social sciences, psychology and statistics, an observational study draws inferences from a sample (statistics), sample to a statistical population, population where the dependent and independent variables, independ ...
*
Observable quantity
In statistics, latent variables (from Latin: present participle of ) are variables that can only be inferred indirectly through a mathematical model from other observable variables that can be directly observed or measured. Such ''latent vari ...
*
Observations and Measurements Observations and Measurements (O&M) is an international standard which defines a conceptual schema encoding for observations, and for features involved in sampling when making observations. While the O&M standard was developed in the context of geog ...
*
Observatory
An observatory is a location used for observing terrestrial, marine, or celestial events. Astronomy, climatology/meteorology, geophysics, oceanography and volcanology are examples of disciplines for which observatories have been constructed.
Th ...
*
Observer effect
*
Noumenon
In philosophy, a noumenon (, ; from ; : noumena) is knowledge posited as an Object (philosophy), object that exists independently of human sense. The term ''noumenon'' is generally used in contrast with, or in relation to, the term ''Phenomena ...
*
Present
The present is the period of time that is occurring now. The present is contrasted with the past, the period of time that has already occurred; and the future, the period of time that has yet to occur.
It is sometimes represented as a hyperplan ...
*
Self
In philosophy, the self is an individual's own being, knowledge, and values, and the relationship between these attributes.
The first-person perspective distinguishes selfhood from personal identity. Whereas "identity" is (literally) same ...
*
Theory ladenness
*
Uncertainty principle
The uncertainty principle, also known as Heisenberg's indeterminacy principle, is a fundamental concept in quantum mechanics. It states that there is a limit to the precision with which certain pairs of physical properties, such as position a ...
*
Unobservable
An unobservable (also called impalpable) is an entity whose existence, nature, properties, qualities or relations are not directly observable by humans. In philosophy of science, typical examples of "unobservables" are the force of gravity, causa ...
References
{{philosophy of science
Aptitude
Cognition
Epistemology of science
Experiments
Knowledge
Perception
Philosophy of science
Scientific method
Sources of knowledge