DreamA dream is a succession of s, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep. Humans spend about two hours dreaming per night, and each dream lasts around 5 to 20 minutes, although the dreamer may perceive the dream as being much longer than this. The content and function of dreams have been topics of scientific, philosophical and religious interest throughout recorded history.
IdeologyAn ideology is a set of beliefs or philosophies attributed to a person or group of persons, especially those held for reasons that are not purely epistemic, in which "practical elements are as prominent as theoretical ones." Formerly applied primarily to economic, political, or religious theories and policies, in a tradition going back to Karl Marx and Friedrich Engels, more recent use treats the term as mainly condemnatory.
Lucid dreamA lucid dream is a type of dream in which the dreamer becomes aware that they are dreaming while dreaming. During a lucid dream, the dreamer may gain some amount of control over the dream characters, narrative, or environment. Lucid dreaming has been studied and reported for many years. Prominent figures from ancient to modern times have been fascinated by lucid dreams and have sought ways to better understand their causes and purpose. Many different theories have emerged as a result of scientific research on the subject and have even been shown in pop culture.
Economic ideologyAn economic ideology is a set of views forming the basis of an ideology on how the economy should run. It differentiates itself from economic theory in being normative rather than just explanatory in its approach, whereas the aim of economic theories is to create accurate explanatory models to describe how an economy currently functions. However, the two are closely interrelated, as underlying economic ideology influences the methodology and theory employed in analysis.
Limit (mathematics)In mathematics, a limit is the value that a function (or sequence) approaches as the input (or index) approaches some value. Limits are essential to calculus and mathematical analysis, and are used to define continuity, derivatives, and integrals. The concept of a limit of a sequence is further generalized to the concept of a limit of a topological net, and is closely related to and direct limit in . In formulas, a limit of a function is usually written as (although a few authors use "Lt" instead of "lim") and is read as "the limit of f of x as x approaches c equals L".
Dream interpretationDream interpretation is the process of assigning meaning to dreams. In many ancient societies, such as those of Egypt and Greece, dreaming was considered a supernatural communication or a means of divine intervention, whose message could be interpreted by people with these associated spiritual powers. In modern times, various schools of psychology and neurobiology have offered theories about the meaning and purpose of dreams.
Limit inferior and limit superiorIn mathematics, the limit inferior and limit superior of a sequence can be thought of as limiting (that is, eventual and extreme) bounds on the sequence. They can be thought of in a similar fashion for a function (see limit of a function). For a set, they are the infimum and supremum of the set's limit points, respectively. In general, when there are multiple objects around which a sequence, function, or set accumulates, the inferior and superior limits extract the smallest and largest of them; the type of object and the measure of size is context-dependent, but the notion of extreme limits is invariant.
Roman villaA Roman villa was typically a farmhouse or country house in the territory of the Roman Republic and the Roman Empire, sometimes reaching extravagant proportions. Nevertheless, the term "Roman villa" generally covers buildings with the common features of being rural (i.e. located outside urban settlements unlike the domus) and residential, with accommodation for the owner. The definition also changed with time: the earliest examples are mostly humble farmhouses in Italy, while from the Republican period a range of larger building types are included.
VillaA villa is a type of house that was originally an ancient Roman upper class country house. Since its origins in the Roman villa, the idea and function of a villa have evolved considerably. After the fall of the Roman Republic, villas became small farming compounds, which were increasingly fortified in Late Antiquity, sometimes transferred to the Church for reuse as a monastery. Then they gradually re-evolved through the Middle Ages into elegant upper-class country homes.