Spacetime

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For other uses of this term, see Spacetime (disambiguation).

Two-dimensional analogy of space–time distortion. Matter changes the geometry of spacetime, this (curved) geometry being interpreted as gravity. White lines do not represent the curvature of space but instead represent the coordinate system imposed on the curved spacetime, which would be rectilinear in a flat spacetime.

In physics, spacetime (or space–time, space time) is any mathematical model that combines space and time into a single continuum. Spacetime is usually interpreted with space as being three-dimensional and time playing the role of a fourth dimension that is of a different sort from the spatial dimensions. According to certain Euclidean space perceptions, the universe has three dimensions of space and one dimension of time. By combining space and time into a single manifold, physicists have significantly simplified a large number of physical theories, as well as described in a more uniform way the workings of the universe at both the supergalactic and subatomic levels.

In classical mechanics, the use of Euclidean space instead of spacetime is appropriate, as time is treated as universal and constant, being independent of the state of motion of an observer. In relativistic contexts, however, time cannot be separated from the three dimensions of space, because the observed rate at which time passes for an object depends on the object's velocity relative to the observer and also on the strength of intense gravitational fields, which can slow the passage of time.

In cosmology, the concept of spacetime combines space and time to a single abstract universe. Mathematically it is a manifold consisting of "events" which are described by some type of coordinate system. Typically three spatial dimensions (length, width, height), and one temporal dimension (time) are required. Dimensions are independent components of a coordinate grid needed to locate a point in a certain defined "space". For example, on the globe the latitude and longitude are two independent coordinates which together uniquely determine a location. In spacetime, a coordinate grid that spans the 3+1 dimensions locates events (rather than just points in space), i.e. time is added as another dimension to the coordinate grid. This way the coordinates specify where and when events occur. However, the unified nature of spacetime and the freedom of coordinate choice it allows imply that to express the temporal coordinate in one coordinate system requires both temporal and spatial coordinates in another coordinate system. Unlike in normal spatial coordinates, there are still restrictions for how measurements can be made spatially and temporally (see Spacetime intervals). These restrictions correspond roughly to a particular mathematical model which differs from Euclidean space in its manifest symmetry.

Until the beginning of the 20th century, time was believed to be independent of motion, progressing at a fixed rate in all reference frames; however, later experiments revealed that time slowed down at higher speeds of the reference frame relative to another reference frame (with such slowing called "time dilation" explained in the theory of "special relativity" ). Many experiments have confirmed time dilation, such as atomic clocks onboard a Space Shuttle running slower than synchronized Earth-bound inertial clocks and the relativistic decay of muons from cosmic ray showers. The duration of time can therefore vary for various events and various reference frames. When dimensions are understood as mere components of the grid system, rather than physical attributes of space, it is easier to understand the alternate dimensional views as being simply the result of coordinate transformations.

The term spacetime has taken on a generalized meaning beyond treating spacetime events with the normal 3+1 dimensions. It is really the combination of space and time. Other proposed spacetime theories include additional dimensions—normally spatial but there exist some speculative theories that include additional temporal dimensions and even some that include dimensions that are neither temporal nor spatial. How many dimensions are needed to describe the universe is still an open question. Speculative theories such as string theory predict 10 or 26 dimensions (with M-theory predicting 11 dimensions: 10 spatial and 1 temporal), but the existence of more than four dimensions would only appear to make a difference at the subatomic level.

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Passion

Passion is a concept that has been used in philosophy. It is different from the current popular connotations of passion which is associated with notions of romance and which is generally seen as a positive and good emotion. The philosophical notion, in contrast, is identified with an innate or biologically driven emotional states such as anger, greed, lust or the other deadly sins. In the philosophical sense, passions can lead to social or spiritual ills, such as punishment from God in Abrahamic faiths, the brutal state of nature presented by Hobbes, the recurrence of karma in dharmic faith. The passions are often used as foils to advocate the pursuit of virtue, the use of reason, dedication to the principles of a faith or other idealistic principles. Different philosophies approach the passions in a number of ways, from the full indulgence of hedonism and nihilism to the forms of moderation found in philosophies like Epicureanism and many conventional religions to the strict abnegation or rejection espoused by Stoicism, Cynicism, and many types of religious monasticism, especially in certain forms of Buddhism, Gnosticism and Jainism.

The subject of the passions has always haunted Western philosophy and, more often than not, aroused harsh judgments. For the passions represent a force of excess and lawlessness in humanity that produces troubling, confusing paradoxes, according to Michel Meyer, who has traced the complex history of philosophic conceptions of the passions by setting forth and contrasting their description in the work of such thinkers as Plato, Aristotle, Augustine, Spinoza, Descartes, Hobbes, Rousseau, Kant, and Freud. The great ruptures that led to passion's condemnation as sin, and to romantic exultation as the truth of existence, are registered and the logic governing them explicated by Meyer, revealing a crucial dilemma: Does passion torture people because it blinds them, or, on the contrary, does it permit them to apprehend who and what we really are?

The seventeenth century Dutch philosopher Spinoza contrasted action with passion, as well as the state of being active with the state of being passive. A passion, in his view, happened when external events affect us partially such that we have confused ideas about these events and their causes. A passive state is when we experience an emotion which Spinoza regarded as a "passivity of the soul."^[1] The body's power is increased or diminished. Emotions are bodily changes plus ideas about these changes which can help or hurt a human.^[1] It happens when the bodily changes we experience are caused primarily by external forces or by a mix of external and internal forces. Spinoza argued that it was much better for a person, himself or herself, to be the only adequate cause of bodily changes, and to act based on an adequate understanding of causes-and-effects with ideas of these changes logically related to each other and to reality; when this happens the person is active, and Spinoza describes the ideas as adequate. But most of the time, this doesn't happen, and Spinoza, along with Freud, saw emotions as more powerful than reason. Spinoza tried to live the life of reason which he advocated.^[2][3][4]

Wisdom

Wisdom is a deep understanding and realizing of people, things, events or situations, resulting in the ability to choose or act to consistently produce the optimum results with a minimum of time and energy. It is the ability to optimally (effectively and efficiently) apply perceptions and knowledge and so produce the desired results. Wisdom is also the comprehension of what is true or right coupled with optimum judgment as to action. Synonyms include: sagacity, discernment, or insight. Wisdom often requires control of one's emotional reactions (the "passions") so that one's principles, reason and knowledge prevail to determine one's actions

A basic philosophical definition of wisdom is to make the best use of knowledge. The opposite of wisdom is folly.

The ancient Greeks considered wisdom to be an important virtue, personified as the goddesses Metis and Athena. To Socrates and Plato, philosophy was literally the love of Wisdom (philo-sophia). This permeates Plato's dialogues, especially The Republic, in which the leaders of his proposed utopia are to be philosopher kings: rulers who understand the Form of the Good and possess the courage to act accordingly. Aristotle, in his Metaphysics, defined wisdom as the understanding of causes, i.e. knowing why things are a certain way, which is deeper than merely knowing that things are a certain way.

Wisdom is also important within Christianity. Jesus emphasized it.^[1][2] Paul the Apostle, in his first epistle to the Corinthians, argued that there is both secular and divine wisdom, urging Christians to pursue the latter. Prudence, which is intimately related to wisdom, became one of the four cardinal virtues of Catholicism. The Christian philosopher Thomas Aquinas considered wisdom to be the "father" (i.e. the cause, measure, and form) of all virtues.

In the Inuit tradition, developing wisdom was the aim of teaching. An Inuit Elder said that a person became wise when they could see what needed to be done and do it successfully without being told what to do.

Nicholas Maxwell, a contemporary philosopher, advocates that academia ought to alter its focus from the acquisition of knowledge to seeking and promoting wisdom, which he defines as the capacity to realize what is of value in life, for oneself and others.^[3]

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