What, When, Where, How, Who?
Time
Introduction, Basic Definitions and Related Concepts:
Time is a basic component of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects. Time has been a major subject of religion, philosophy, and science, but defining time in a non-controversial manner applicable to all fields of study has consistently eluded the greatest scholars. In physics and other sciences, time is considered one of the few fundamental quantities.[2] Time is used to define other quantites – such as velocity – and defining time in terms of such quantities would result in circularity of definition.[3] An operational definition of time, wherein one says that observing a certain number of repetitions of one or another standard cyclical event (such as the passage of a free-swinging pendulum) constitutes one standard unit such as the second, has a high utility value in the conduct of both advanced experiments and everyday affairs of life. The operational definition leaves aside the question whether there is something called time, apart from the counting activity just mentioned, that flows and that can be measured. Investigations of a single continuum called space-time brings the nature of time into association with related questions into the nature of space, questions that have their roots in the works of early students of natural philosophy. Among philosophers, there are two distinct viewpoints on time. One view is that time is part of the fundamental structure of the universe, a dimension in which events occur in sequence. Sir Isaac Newton subscribed to this realist view, and hence it is sometimes referred to as Newtonian time.[4][5] The opposing view is that time does not refer to any kind of "container" that events and objects "move through", nor to any entity that "flows", but that it is instead part of a fundamental intellectual structure (together with space and number) within which humans sequence and compare events. This second view, in the tradition of Gottfried Leibniz[6] and Immanuel Kant,[7][8] holds that time is not itself some thing and therefore is not to be measured. Temporal measurement has occupied scientists and technologists, and was a prime motivation in astronomy. A religion is a set of beliefs and practices often organized around supernatural and moral claims, and often codified as prayer, ritual, and religious law. Religion also encompasses ancestral or cultural traditions, writings, history, and mythology, as well as personal faith and mystic experience. The term "religion" refers to both the personal practices related to communal faith and to group rituals and communication stemming from shared conviction. In the frame of European religious thought,[1] religions present a common quality, the "hallmark of patriarchal religious thought": the division of the world in two comprehensive domains, one sacred, the other profane.[2] Religion is often described as a communal system for the coherence of belief focusing on a system of thought, unseen being, person, or object, that is considered to be supernatural, sacred, divine, or of the highest truth. Moral codes, practices, values, institutions, tradition, rituals, and scriptures are often traditionally associated with the core belief, and these may have some overlap with concepts in secular philosophy. Religion is also often described as a "way of life". The development of religion has taken many forms in various cultures. "Organized religion" generally refers to an organization of people supporting the exercise of some religion with a prescribed set of beliefs, often taking the form of a legal entity (see religion-supporting organization). Other religions believe in personal revelation. "Religion" is sometimes used interchangeably with "faith" or "belief system,"[3] but is more socially defined than that of personal convictions. The English word religion is in use since the 13th century, loaned from Anglo-French religiun (11th century), ultimately from the Latin religio, "reverence for God or the gods, careful pondering of divine things, piety, the res divinae".[4] Philosophy is the discipline concerned with questions of how one should live (ethics); what sorts of things exist and what are their essential natures (metaphysics); what counts as genuine knowledge (epistemology); and what are the correct principles of reasoning (logic).[1][2] The word is of Ancient Greek origin: φιλοσοφία (philosophía), meaning love of wisdom.[3] Every definition of philosophy is controversial. The field has historically expanded and changed depending upon what kinds of questions were interesting or relevant in a given era. It is generally agreed that philosophy is a method, rather than a set of claims, propositions, or theories. Its investigations are based upon rational thinking, striving to make no unexamined assumptions and no leaps based on faith or pure analogy. Different philosophers have had varied ideas about the nature of reason. There is also disagreement about the subject matter of philosophy. Some think that philosophy examines the process of inquiry itself. Others, that there are essentially philosophical propositions which it is the task of philosophy to answer.[4] Although the word "philosophy" originates in Ancient Greece, many figures in the history of other cultures have addressed similar topics in similar ways.[5] The philosophers of East and South Asia are discussed in Eastern philosophy, while the philosophers of North Africa and the Middle East, because of their strong interactions with Europe, are usually considered part of Western philosophy. In its broadest sense, science (from the Latin scientia, meaning "knowledge") refers to any systematic knowledge or practice. In its more usual restricted sense, science refers to a system of acquiring knowledge based on the scientific method, as well as to the organized body of knowledge gained through such research.[1][2] Fields of science are commonly classified along two major lines:
- Natural sciences, which study natural phenomena (including biological life), and Social sciences, which study human behavior and societies.
These groupings are
empirical sciences, which means the knowledge must
be based on
observable
phenomena and capable of being
experimented for its
validity by other researchers working under the same
conditions.[2]
Mathematics, which is sometimes classified within a
third group of science called
formal science, has both similarities and
differences with the natural and social sciences.[2]
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.[2]
Formal science, which also includes
statistics and
logic, is vital to the empirical sciences. Major
advances in formal science have often led to major
advances in the physical and biological sciences. The
formal sciences are essential in the formation of
hypotheses,
theories, and
laws,[2]
both in discovering and describing how things work
(natural sciences) and how people think and act (social
sciences). Sometimes termed
experimental science to differentiate it from
applied science, which is the application of
scientific research to specific human needs, though the
two are often interconnected. The word science
comes through the
Old French, and is derived from the
Latin word scientia
for
knowledge, the nominal form of the verb
scire, "to
know". The
Proto-Indo-European (PIE) root that yields scire
is *skei-, meaning to "cut, separate, or
discern". Physics is the
science of
matter[1]
and its
motion,[2][3]
as well as
space and
time[4][5]
— the
science that deals with concepts such as
force,
energy,
mass, and
charge. Physics is an
experimental
science;[6]
it is the general analysis of
nature, conducted to understand how the world around
us behaves.[7]
Physics is one of the oldest academic disciplines,
having
emerged as a modern science in the 17th century,[8]
and through its modern subfield of
astronomy, it may be the oldest of all.[9]
Those who work professionally in the field are known as
physicists. Advances in physics often translate to
the technological sector, and sometimes influence the
other sciences, as well as mathematics and philosophy.
For example, advances in the understanding of
electromagnetism have led to the widespread use of
electrically driven devices (televisions, computers,
home appliances etc.); advances in
thermodynamics led to the development of motorized
transport; and advances in
mechanics led to the development of
calculus,
quantum chemistry, and the use of instruments such
as the
electron microscope in
microbiology. Today, physics is a broad and highly
developed subject. Research is often divided into four
subfields: condensed matter physics; atomic, molecular,
and optical physics; high-energy physics; and astronomy
and astrophysics. Most physicists also specialize in
either
theoretical or
experimental research, the former dealing with the
development of new theories, and the latter dealing with
the experimental testing of theories and the discovery
of new phenomena. Despite important discoveries during
the last four centuries, there are a number of
unsolved problems in physics, and many areas of
active research. Fundamental means
serving as an original or generating source : primary
<a discovery fundamental to
modern computers>
serving as a basis
supporting existence or determining essential structure
or function : basic
of or relating to
essential structure, function, or facts : radical
<fundamental change>;
also
: of or dealing with general principles
rather than practical application <fundamental
science>
adhering to
fundamentalism
of, relating to, or produced by the lowest component of
a complex vibration
of central importance : principal
<fundamental purpose>
belonging to one's
innate or ingrained characteristics : deep-rooted
<her fundamental good humor>.
Quantity is a kind of
property which exists as magnitude or multitude. It is
among the basic classes of things along with
quality,
substance,
change, and
relation. Quantity was first introduced as
quantum, an
entity having quantity. Being a fundamental term,
quantity is used to refer to any type of quantitative
properties or attributes of things. Some quantities are
such by their inner nature (as number), while others are
functioning as states (properties, dimensions,
attributes) of things such as heavy and light, long and
short, broad and narrow, small and great, or much and
little. One form of much, muchly is used to say that
something is likely to happen. A small quantity is
sometimes referred to as a quantulum. Two basic
divisions of quantity,
magnitude and multitude (or
number), imply the principal distinction between
continuity (continuum)
and
discontinuity. Under the names of multitude come
what is discontinuous and discrete and divisible into
indivisibles, all cases of collective nouns: army,
fleet, flock, government, company, party, people,
chorus, crowd, mess, and number. Under the names of
magnitude come what is continuous and unified and
divisible into divisibles, all cases of non-collective
nouns: the universe, matter, mass, energy, liquid,
material, animal, plant, tree. Along with analyzing
its nature and classification, the issues of quantity
involve such closely related topics as the relation of
magnitudes and multitudes, dimensionality, equality,
proportion, the measurements of quantities, the units of
measurements, number and numbering systems, the types of
numbers and their relations to each other as numerical
ratios. Thus quantity is a property that exists in a
range of magnitudes or multitudes. In
physics, velocity is defined as the
rate of change of
position. It is a
vector
physical quantity; both speed and direction
are required to define it. In the
SI (metric) system, it is measured in
metres per second: (m/s) or ms-1. The
scalar
absolute value (magnitude)
of velocity is
speed. For example, "5 metres per second" is a
scalar and not a vector, whereas "5 metres per
second east" is a vector. The average velocity
v of an object moving through a displacement
during a time interval (Δt)
is described by the formula:
The rate of change of velocity is referred to as
acceleration. The instant velocity vector v
of an object that has positions x(t) at
time t and x(t+Δt)
at time t+Δt, can be
computed as the
derivative of position:
The equation for an object's velocity can be obtained
mathematically by taking the
integral of the equation for its acceleration
beginning from some initial period time
t0 to some
point in time later tn.
The final velocity v of an object which starts
with velocity u and then accelerates at constant
acceleration a for a period of time
(Δt) is:
The average velocity of an object undergoing constant
acceleration is
,
where u is the initial velocity and v is
the final velocity. In
logic, begging the question has traditionally
described a type of
logical fallacy (also called petitio principii)
in which the proposition to be proved is assumed
implicitly or explicitly in one of the premises.[1][2][3][4][5][6]
Begging the question is related to the fallacy
known as circular argument, circulus in
probando, vicious circle or circular
reasoning. The first known definition in the West is
by the
Greek
philosopher
Aristotle around
350 B.C., in his book
Prior Analytics. In recent decades, "begs the
question" has been used increasingly but incorrectly to
mean that a statement invites another obvious question.[7]
The Latin term was incorporated into
English in the
16th century. The Latin version, Petitio
Principii (from peto, petere, petivi, petitus:
attack, aim at, desire, beg, entreat, ask (for), reach
towards, make for; principii, genitive of
principium: beginning or principle), literally means
"begging or taking for granted of the beginning or of a
principle." That is, the premise (the principle, the
beginning) depends on the truth of the very matter in
question. The Latin phrase comes from the
Greek en archei aiteisthai in
Aristotle's Prior Analytics II xvi:
Begging or assuming the point at issue consists (to take the expression in its widest sense) in failing to demonstrate the required proposition. But there are several other ways in which this may happen; for example, if the argument has not taken syllogistic form at all […]. If, however, the relation of B to C is such that they are identical, or that they are clearly convertible, or that one applies to the other, then he is begging the point at issue.
Fowler's Deductive Logic (1887) argues that the Latin origin is more properly Petitio Quæsiti which translates as "begging the question". A definition is a statement of the meaning of a word or phrase. The term to be defined is known as the definiendum (Latin: that which is to be defined). The words which define it are known as the definiens (Latin: that which is doing the defining).[1] A definition may either give the meaning that a term bears in general use (a descriptive definition), or that which the speaker intends to impose upon it for the purpose of his or her discourse (a stipulative definition). Stipulative definitions differ from descriptive definitions in that they prescribe a new meaning either to a term already in use or to a new term. A descriptive definition can be shown to be right or wrong by comparison to usage, while a stipulative definition cannot. A stipulative definition, however, may be more or less useful. A kind of often useful stipulative definitions are precising definitions. A persuasive definition, named by C.L. Stevenson, is a form of stipulative definition which purports to describe the 'true' or 'commonly accepted' meaning of a term, while in reality stipulating an altered use, perhaps as an argument for some view, for example that some system of government is democratic. Stevenson also notes that some definitions are 'legal' or 'coercive', whose object is to create or alter rights, duties or crimes.[2] An intensional definition, also called a connotative definition, specifies the necessary and sufficient conditions for a thing being a member of a specific set. Any definition that attempts to set out the essence of something, such as that by genus and differentia, is an intensional definition. An operational definition is a showing of something — such as a variable, term, or object — in terms of the specific process or set of validation tests used to determine its presence and quantity. Properties described in this manner must be publicly accessible so that persons other than the definer can independently measure or test for them at will. An operational definition is generally designed to model a conceptual definition. The most basic operational definition is a process for identification of an object by distinguishing it from its background of empirical experience. The binary version produces either the result that the object exists, or that it doesn't, in the experiential field to which it is applied. The classifier version results in discrimination between what is part of the object and what is not part of it. This is also discussed in terms of semantics, pattern recognition, and operational techniques, such as regression. For example, the weight of an object may be operationally defined in terms of the specific steps of putting an object on a weighing scale. The weight is whatever results from following the measurement procedure, which can in principle be repeated by anyone. It is intentionally not defined in terms of some intrinsic or private essence. The operational definition of weight is just the result of what happens when the defined procedure is followed. In other words, what's being defined is how to measure weight for any arbitrary object, and only incidentally the weight of a given object. The second (SI symbol: s), sometimes abbreviated sec., is the name of a unit of time, and is the International System of Units (SI) base unit of time. SI prefixes are frequently combined with the word second to denote subdivisions of the second, e.g., the millisecond (one thousandth of a second) and nanosecond (one billionth of a second). Though SI prefixes may also be used to form multiples of the second (such as “kilosecond,” or one thousand seconds), such units are rarely used in practice. More commonly encountered, non-SI units of time such as the minute, hour, and day increase by multiples of 60 and 24 (rather than by powers of ten as in the SI system).