On the Knowledge of the Celestial Bodies: al-Išārāt wa at-Tanbīhāt X.9 and Its Reception in the Commentary Tradition

2018 ◽

Vol 6 (1-2) ◽

pp. 27-54

Author(s):

Glen M. Cooper

Keyword(s):

Body Politic ◽

The Body ◽

Ibn Sina ◽

Lunar Phases ◽

Divine Judgment ◽

Celestial Bodies ◽

Commentary Tradition

Conceptualized as a relationship between the patient, his illness, its resolution, the celestial bodies, and the doctor, and expressed through metaphors, such as divine judgment, or effects of the stars, crises and critical days were important elements of Galenic therapy. While the early Arabic physicians maintained Galenic imagery, Ibn Sīnā (d. 1037 CE) and his followers introduced new imagery that omitted supernatural influences, and emphasized physical agents. The crisis was now described as a separation instead of a verdict, and the critical days were caused by the lunar phases alone. The “body politic” metaphor was introduced to describe medical crises. By closely examining the writings of Ibn al-Nafīs (d. 1288 CE) on the Canon of Ibn Sīnā and the Aphorisms of Hippocrates, these shifts in imagery are analysed in detail, and their implications for our understanding of a period that has been dismissed as “post-decline” and devoid of innovation.

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Symmetric Multistep Methods Revisited: II. Numerical Experiments

International Astronomical Union Colloquium ◽

10.1017/s0252921100031602 ◽

1999 ◽

Vol 173 ◽

pp. 309-314 ◽

Cited By ~ 3

Author(s):

T. Fukushima

Keyword(s):

Multistep Methods ◽

Computational Time ◽

Integration Time ◽

Implicit Methods ◽

Symmetric Methods ◽

Celestial Bodies ◽

The Stability ◽

Predictor Corrector ◽

Symmetric Multistep Methods ◽

Integration Errors

AbstractBy using the stability condition and general formulas developed by Fukushima (1998 = Paper I) we discovered that, just as in the case of the explicit symmetric multistep methods (Quinlan and Tremaine, 1990), when integrating orbital motions of celestial bodies, the implicit symmetric multistep methods used in the predictor-corrector manner lead to integration errors in position which grow linearly with the integration time if the stepsizes adopted are sufficiently small and if the number of corrections is sufficiently large, say two or three. We confirmed also that the symmetric methods (explicit or implicit) would produce the stepsize-dependent instabilities/resonances, which was discovered by A. Toomre in 1991 and confirmed by G.D. Quinlan for some high order explicit methods. Although the implicit methods require twice or more computational time for the same stepsize than the explicit symmetric ones do, they seem to be preferable since they reduce these undesirable features significantly.

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Hipparchus of Nicaea and the Commentary Tradition

SSRN Electronic Journal ◽

10.2139/ssrn.1607870 ◽

2010 ◽

Author(s):

Caroline B. Bishop

Keyword(s):

Commentary Tradition

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III. On the nature and construction of the sun and fixed stars

Philosophical Transactions of the Royal Society of London ◽

10.1098/rstl.1795.0005 ◽

1795 ◽

Vol 85 ◽

pp. 46-72 ◽

Cited By ~ 13

Keyword(s):

Central Body ◽

Planetary System ◽

Considerable Progress ◽

The Sun ◽

Great Satisfaction ◽

The Earth ◽

The World ◽

Celestial Bodies ◽

The Universe ◽

Made In

Among the celestial bodies the sun is certainly the first which should attract our notice. It is a fountain of light that illuminates the world! it is the cause of that heat which maintains the productive power of nature, and makes the earth a fit habitation for man! it is the central body of the planetary system; and what renders a knowledge of its nature still more interesting to us is, that the numberless stars which compose the universe, appear, by the strictest analogy, to be similar bodies. Their innate light is so intense, that it reaches the eye of the observer from the remotest regions of space, and forcibly claims his notice. Now, if we are convinced that an inquiry into the nature and properties of the sun is highly worthy of our notice, we may also with great satisfaction reflect on the considerable progress that has already been made in our knowledge of this eminent body. It would require a long detail to enumerate all the various discoveries which have been made on this subject; I shall, therefore, content myself with giving only the most capital of them.

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Cycles and circulation: a theme in the history of biology and medicine

History & Philosophy of the Life Sciences ◽

10.1007/s40656-021-00425-3 ◽

2021 ◽

Vol 43 (3) ◽

Author(s):

Nick Hopwood ◽

Staffan Müller-Wille ◽

Janet Browne ◽

Christiane Groeben ◽

Shigehisa Kuriyama ◽

...

Keyword(s):

Natural Philosophy ◽

Life Cycles ◽

Modern Times ◽

Systems Ecology ◽

The Face ◽

History Of ◽

Celestial Bodies ◽

Reproductive Cycles ◽

Economics And Biology

AbstractWe invite systematic consideration of the metaphors of cycles and circulation as a long-term theme in the history of the life and environmental sciences and medicine. Ubiquitous in ancient religious and philosophical traditions, especially in representing the seasons and the motions of celestial bodies, circles once symbolized perfection. Over the centuries cyclic images in western medicine, natural philosophy, natural history and eventually biology gained independence from cosmology and theology and came to depend less on strictly circular forms. As potent ‘canonical icons’, cycles also interacted with representations of linear and irreversible change, including arrows, arcs, scales, series and trees, as in theories of the Earth and of evolution. In modern times life cycles and reproductive cycles have often been held to characterize life, in some cases especially female life, while human efforts selectively to foster and disrupt these cycles have harnessed their productivity in medicine and agriculture. But strong cyclic metaphors have continued to link physiology and climatology, medicine and economics, and biology and manufacturing, notably through the relations between land, food and population. From the grand nineteenth-century transformations of matter to systems ecology, the circulation of molecules through organic and inorganic compartments has posed the problem of maintaining identity in the face of flux and highlights the seductive ability of cyclic schemes to imply closure where no original state was in fact restored. More concerted attention to cycles and circulation will enrich analyses of the power of metaphors to naturalize understandings of life and their shaping by practical interests and political imaginations.

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The celestial bodies motion theories: on the required accuracy of the motion theories of the perturbing bodies

Planetary and Space Science ◽

10.1016/s0032-0633(97)00180-3 ◽

1997 ◽

Vol 45 (12) ◽

pp. 1595-1606

Author(s):

E.D. Kuznetsov

Keyword(s):

Celestial Bodies

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Note on the intensity decrement in the balmer series

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1919.0042 ◽

1919 ◽

Vol 96 (675) ◽

pp. 112-119 ◽

Cited By ~ 7

Keyword(s):

Hydrogen Atom ◽

Low Pressure ◽

Quantitative Comparison ◽

The Sun ◽

Previous Knowledge ◽

Balmer Series ◽

Celestial Bodies ◽

Theoretical Considerations

One of the most remarkable examples of spectrum lines which are common in celestial bodies, but which have hitherto resisted all attempts to reproduce them in the laboratory, is afforded by the higher members of the Balmer series of hydrogen. As many as 29 members of this series have been observed by Dyson and Evershed in the chromosphere of the sun, but the greatest number observed in the laboratory by Ames and by Cornu was only 13, and the last of these were of such a character that it would hardly have been possible to record them without a previous knowledge of their localisation. In many respects the failure to reproduce in the laboratory lines whose chemical origin is known, and which are so prominent in celestial spectra, is even more conspicuous than in the case of the nebular and coronal lines, which cannot yet be referred to any atom known in chemistry, and which may be due to substances which do not, or perhaps cannot, exist under terrestrial conditions. A further interest has been added to the problem by the important theoretical wrork of Bohr, whose theory of the production of the Balmer series requires that the space occupied by a hydrogen atom, in the process of emitting lines of the higher members of the Balmer series, is such that these radiations cannot be expected to be visible except under conditions of extremely low pressure. Bohr has pointed out that this view is consistent with the appearance of the lines in celestial spectra, and our inability to produce them under the conditions ordinarily obtaining in the laboratory. Liveing and Dewar have found that in a mixture of the more volatile gases of the atmosphere, consisting mainly of neon and helium and containing hydrogen, the Balmer series could be traced as far as the ninth member; and in a recent investigation we have made a quantitative comparison of the distribution of intensity in the earlier members of the series in hydrogen, and in neon containing hydrogen as an impurity. This observation of Liveing and Dewar is remarkable, but we have recently found that similar results can be obtained in helium containing hydrogen at pressures so great that, on the theoretical considerations above referred to, it would seem impossible that these radiations should be detected.

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