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Portuguese Claims to the Exclusive Domination of the Indian Ocean Regions
Published in K.S. Mathew, Shipbuilding, Navigation and the Portuguese in Pre-modern India, 2017
This was an instrument used by D. Manuel. The Ptolemaic geocentric system was shown by a small globe – the earth – in the centre of the celestial sphere which is delineated by rings representing the polar circles, the tropics, the equator and ecliptic. It is of engraved brass with a globe of wood; it is probably of the fifteenth century. Deriving from Ptolemy’s astrolabon, the armillary sphere in Islam appears mainly to have been, like Ptolemy’s instrument, an observational instrument. To be effective it had to be large. In the European tradition, the armillary sphere is not primarily an observational instrument. It was primarily used in Europe for demonstrational or didactic purposes. An elaborate sphere with star pointers attached to the rings could show the apparent rotation of the stars about the pole and serve also for the solution of simple problems in spherical trigonometry. An instrument derived in the sixteenth century from the armillary sphere became a useful nautical instrument.
Introduction
Published in Jim Mason, Innovating Construction Law, 2021
In her 2017 paper, Margaret Radin1 wrote about the Ancient Greek Philosopher, Ptolemy (85 to 165 AD), and his geocentric theory which was to dominate how we thought about our place in the universe for 1400 years. Ptolemy spent many years studying the movement of the stars and planets around the Earth and was of the very firm view, and convinced others, that the Earth was the centre of the universe (the geocentric theory). There was one flaw in his grand plan – occasionally, the planets would not follow a regular orbit pattern and go off, on what a judge once deemed, “a frolic of their own.”2 That is, the planets did not follow the orbital pattern.
Introduction
Published in Matt Fajkus, Dason Whitsett, Architectural Science and the Sun, 2018
From Pythagoras to Anaxagoras, progress was made in the definition of light and dark, as well as an improved understanding of darkness as the absence of light, rather than as an entity in itself. In the 4th century b.c., Aristotle deeply explored ideas of sensory perception, and he attempted to break down the components of perception into their own respective realms, including the human biological sensory component, the medium through which light traveled, the object being seen, and the process of transmission between each element. He advocated a theory of intromission in which the eye received rays rather than directing them outward. Furthermore, Aristotle proposed a more holistic view of light and the circumstances in which it operates in a more specific and general sense.7 The predominant way of understanding the universe at the time was the assumption that the Earth was at the center with the other celestial bodies orbiting around it. The assumption that the Earth is at the center of the orbits of celestial bodies is known as the geocentric model. Aristotle laid the foundations of modern science with his argument that theory should agree with observations. He advocated a geocentric model of the universe composed of concentric spheres centered around the Earth. In his conception, the sun’s sphere was between Venus and Mars. This model was largely accepted even though the Greeks had recorded planetary phenomena with contradictions to this notion, which were unexplained by Aristotle.8 Aristotle began to speculate that “vision” goes beyond what is literally seen, and that concepts can be understood, or “seen,” without having been directly witnessed.
Frames of spatial reference in five Australian languages
Published in Spatial Cognition & Computation, 2022
Bill Palmer, Dorothea Hoffmann, Joe Blythe, Alice Gaby, Bill Pascoe, Maïa Ponsonnet
Geocentric FoR is an allocentric extrinsic relation in which an asymmetry is assigned to a situation on the basis of environmental features or other coordinates outside the spatial array of figure and ground, other than the observer: e.g. the house is east/seaward/downriver from the shop, where a domain is projected off the ground shop on the basis of the absolute coordinate east; the location of a landmark (the sea in seaward); or the geomorphic direction of flow of a watercourse (the river in downriver). The scope of the term “absolute” varies widely in the literature on spatial language. In Levinson’s original typology and Bohnemeyer’s classification of geocentric subtypes, absolute refers to a subset of allocentric extrinsic relations that involves fixed abstract axes such as cardinal terms, and notions such as downriver where the encoded direction is abstracted from the actual direction of flow of the river (Bohnemeyer & O’Meara, 2012, p. 5; Bohnemeyer et al., 2015, pp. 175-176; Levinson, 2003, p. 48–49). However, in the spatial descriptive literature, “absolute” is often used to refer to all allocentric extrinsic frames (= geocentric). Danziger (2010) classifies as absolute all allocentric relations in which the anchor is not the ground (i.e. is extrinsic), where, “the Anchor is located in the landscape or the cosmology surrounding the Figure-Ground scene” (Danziger, 2010, p. 169). Palmer (2015) uses “absolute” in a similar way, as does Hoffmann’s (2016, 2019) work on space in Australian languages, among others. In the present article, we adopt the more precise classification of referring to all extrinsic allocentric spatial relations as geocentric (§2.2.4).