Presentism (philosophy of time)
Saint Augustine
Augustine of Hippo
Augustine of Hippo , also known as Augustine, St. Augustine, St. Austin, St. Augoustinos, Blessed Augustine, or St. Augustine the Blessed, was Bishop of Hippo Regius . He was a Latin-speaking philosopher and theologian who lived in the Roman Africa Province...

 proposed that the present is a knife edge between the past and the future and could not contain any extended period of time. This seems evident
Evidence in its broadest sense includes everything that is used to determine or demonstrate the truth of an assertion. Giving or procuring evidence is the process of using those things that are either presumed to be true, or were themselves proven via evidence, to demonstrate an assertion's truth...

 because, if the present is extended, it must have separate parts - but these must be simultaneous
Simultaneity is the property of two events happening at the same time in at least one frame of reference. The word derives from the Latin simul, at the same time plus the suffix -taneous, abstracted from spontaneous .The noun simult means a supernatural coincidence, two or more divinely...

 if they are truly part of the present. According to early philosophers, time cannot be both past and simultaneously present, so it is not extended. Contrary to Saint Augustine, some philosophers propose that conscious experience is extended in time. For instance, William James
William James
William James was a pioneering American psychologist and philosopher who was trained as a physician. He wrote influential books on the young science of psychology, educational psychology, psychology of religious experience and mysticism, and on the philosophy of pragmatism...

 said that time is "the short duration of which we are immediately and incessantly sensible". Augustine proposed that God is outside of time and present for all times, in eternity
While in the popular mind, eternity often simply means existence for a limitless amount of time, many have used it to refer to a timeless existence altogether outside time. By contrast, infinite temporal existence is then called sempiternity. Something eternal exists outside time; by contrast,...

. Other early philosophers who were presentists include the Buddhists
Buddhism is a religion and philosophy encompassing a variety of traditions, beliefs and practices, largely based on teachings attributed to Siddhartha Gautama, commonly known as the Buddha . The Buddha lived and taught in the northeastern Indian subcontinent some time between the 6th and 4th...

 (in the tradition of Indian Buddhism). A leading scholar from the modern era on Buddhist philosophy
Buddhist philosophy
Buddhist philosophy deals extensively with problems in metaphysics, phenomenology, ethics, and epistemology.Some scholars assert that early Buddhist philosophy did not engage in ontological or metaphysical speculation, but was based instead on empirical evidence gained by the sense organs...

 is Stcherbatsky, who has written extensively on Buddhist presentism: "Everything past is unreal, everything future is unreal, everything imagined, absent, mental… is unreal… Ultimately real is only the present moment of physical efficiency [i.e., causation
Causation may refer to:* Causation , a key component to establish liability in both criminal and civil law* Causation in English law defines the requirement for liability in negligence...


According to J. M. E. McTaggart
J. M. E. McTaggart
John McTaggart was an idealist metaphysician. For most of his life McTaggart was a fellow and lecturer in philosophy at Trinity College, Cambridge. He was an exponent of the philosophy of Hegel and among the most notable of the British idealists.-Personal life:J. M. E. McTaggart was born in 1866...

's The Unreality of Time
The Unreality of Time
The Unreality of Time is the best-known philosophical work of the Cambridge idealist J. M. E. McTaggart. In the paper, first published in 1908 in Mind 17: 457-73, McTaggart argues that time is unreal because our descriptions of time are either contradictory, circular, or insufficient...

, there are two ways of referring to events: the 'A Series'
B-Theory of time
The B-theory of time is a term, given to one of two positions taken by theorists, in the philosophy of time. The labels, A-theory and B-theory, are derived from the analysis of time and change developed by Cambridge philosopher J. M. E...

 (also known as 'tensed time': yesterday, today, tomorrow) and the 'B Series'
B-Theory of time
The B-theory of time is a term, given to one of two positions taken by theorists, in the philosophy of time. The labels, A-theory and B-theory, are derived from the analysis of time and change developed by Cambridge philosopher J. M. E...

 (or 'untensed time': Monday, Tuesday, Wednesday). Presentism entails that the A Series is fundamental and that the B Series alone is not sufficient. Presentists maintain that temporal discourse requires the use of tenses, whereas the "Old B-Theorists" argued that tensed language could be reduced to tensless facts (Dyke, 2004).

In the modern theory of relativity
Theory of relativity
The theory of relativity, or simply relativity, encompasses two theories of Albert Einstein: special relativity and general relativity. However, the word relativity is sometimes used in reference to Galilean invariance....

, the conceptual observer
Observation is either an activity of a living being, such as a human, consisting of receiving knowledge of the outside world through the senses, or the recording of data using scientific instruments. The term may also refer to any data collected during this activity...

 is at a geometric point
Point (geometry)
In geometry, topology and related branches of mathematics a spatial point is a primitive notion upon which other concepts may be defined. In geometry, points are zero-dimensional; i.e., they do not have volume, area, length, or any other higher-dimensional analogue. In branches of mathematics...

 in both space and time at the apex of the 'light cone
Light cone
A light cone is the path that a flash of light, emanating from a single event and traveling in all directions, would take through spacetime...

' which observes events laid out in time as well as space. Different observers can disagree on whether two events at different locations occurred simultaneously depending if the observers are in relative motion (see relativity of simultaneity
Relativity of simultaneity
In physics, the relativity of simultaneity is the concept that simultaneity–whether two events occur at the same time–is not absolute, but depends on the observer's reference frame. According to the special theory of relativity, it is impossible to say in an absolute sense whether two events occur...

). This theory depends upon the idea of time as an extended thing and has been confirmed by experiment, thus giving rise to a philosophical viewpoint known as four dimensionalism
Four dimensionalism
In philosophy, four-dimensionalism is an ontological position that an object's persistence through time is like its extension through space and an object that exists in time has temporal parts in the various subregions of the total region of time it occupies.Eternalism is a...

. However, although the contents of an observation are time-extended, the conceptual observer, being a geometric point at the origin of the light cone, is not extended in time or space. This analysis contains a paradox
Similar to Circular reasoning, A paradox is a seemingly true statement or group of statements that lead to a contradiction or a situation which seems to defy logic or intuition...

 in which the conceptual observer contains nothing, even though any real observer would need to be the extended contents of an observation to exist. This paradox is partially resolved in Relativity theory by defining a 'frame of reference
Frame of reference
A frame of reference in physics, may refer to a coordinate system or set of axes within which to measure the position, orientation, and other properties of objects in it, or it may refer to an observational reference frame tied to the state of motion of an observer.It may also refer to both an...

' to encompass the measuring instruments used by an observer. This reduces the time separation between instruments to a set of constant intervals.

See also

  • Eternalism
  • Consciousness
    Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...

  • Libertarianism
    Libertarianism (metaphysics)
    Libertarianism is one of the main philosophical positions related to the problems of free will and determinism, which are part of the larger domain of metaphysics. In particular, libertarianism, which is an incompatibilist position, argues that free will is logically incompatible with a...

  • Metaphysics
    Metaphysics is a branch of philosophy concerned with explaining the fundamental nature of being and the world, although the term is not easily defined. Traditionally, metaphysics attempts to answer two basic questions in the broadest possible terms:...

External links

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