4,541 research outputs found

    The Limits of Eudaimonia in the Nicomachean Ethics

    Get PDF
    In Book I of his Nicomachean Ethics (NE), Aristotle defines happiness, or eudaimonia, in accordance with an argument he makes regarding the distinctive function of human beings. In this paper, I argue that, despite this argument, there are moments in the NE where Aristotle appeals to elements of happiness that don’t follow from the function argument itself. The place of these elements in Aristotle’s account of happiness should, therefore, be a matter of perplexity. For, how can Aristotle appeal to elements of happiness not entailed by his argument for what happiness involves? I will examine two instances that exemplify the sort of appeal to outside elements that I have in mind. The first deals with Aristotle’s reference, in NE, I, 8, to certain goods—ancestry, children, beauty—goods unrelated to man’s function or his fulfillment of it, but nevertheless required for his happiness. The second instance involves pleasure. Aristotle makes various arguments, both in Books I and X of the NE, that tie pleasure to the activity of the soul, and the function argument in turn. However, none of these arguments succeeds in demonstrating that pleasure would necessarily follow from this activity. Taken together then, these two examples demonstrate the extent to which Aristotle’s definition of happiness is more inclusive than his function argument permits

    An X-ray View of Radio Sources

    Full text link
    We review recent examples where the synergy between radio and X-ray observations has led to substantial progress in understanding astronomical systems. The sub-arcsecond imaging capabilities of the Chandra X-ray observatory provides a 100-fold improvement for comparing X-ray and radio structures. We specifically discuss examples which provide insight into the outflow of material and energy from pulsars and supernovae, the centers of clusters of galaxies, and the nuclei of quasars.Comment: 17 pages, 13 figures. Talk presented at the JENAM-2003 Symposium, "Radio Astronomy at 70: from Karl Jansky to microjansky," Budapest, Hungary, 27-30 August 2003. To be published by EDP Sciences, eds. L. Gurvits, S. Frey, and S. Rawling

    Scientific investigations with the data base HEAO-1 scanning modulator collimator

    Get PDF
    The hardware specification for the Scanning Modulation Collimator (MC) experiment on HEAO-1 was to measure positions of bright (greater than 10(exp -11) ergs/cm(exp 2)s), hard (1 to 15 keV) x-ray sources to 5-10 arcsec, and to measure their size and structure in three energy bands down to 10 arcsec resolution. The scientific purpose of this specification was to enable the identification of these x-ray sources with optical and radio objects in order to elucidate the x-ray emission mechanism and the nature of the candidate astronomical system. The experiment was an outstanding success. Hardware systems functioned perfectly although loss of one (out of eight) proportional counters degraded our sensitivity by about 10 percent. Our aspect solution of 7 arcsec precision, allowed us to achieve statistic-limited location precision for all but the strongest sources. We vigorously pursued a strategy of determining the scientific importance of each identification, and of publishing each scientific result as it came along

    A medieval fallacy: the crystalline lens in the center of the eye.

    Get PDF
    ObjectiveTo determine whether, as most modern historians have written, ancient Greco-Roman authors believed the crystalline lens is positioned in the center of the eye.BackgroundHistorians have written that statements about cataract couching by Celsus, or perhaps Galen of Pergamon, suggested a centrally located lens. Celsus specifically wrote that a couching needle placed intermediate between the corneal limbus and the lateral canthus enters an empty space, presumed to represent the posterior chamber.MethodsAncient ophthalmic literature was analyzed to understand where these authors believed the crystalline lens was positioned. In order to estimate where Celsus proposed entering the eye during couching, we prospectively measured the distance from the temporal corneal limbus to the lateral canthus in 30 healthy adults.ResultsRufus of Ephesus and Galen wrote that the lens is anterior enough to contact the iris. Galen wrote that the lens equator joins other ocular structures at the corneoscleral junction. In 30 subjects, half the distance from the temporal corneal limbus to the lateral canthus was a mean of 4.5 mm (range: 3.3-5.3 mm). Descriptions of couching by Celsus and others are consistent with pars plana entry of the couching needle. Anterior angulation of the needle would permit contact of the needle with the lens.ConclusionAncient descriptions of anatomy and couching do not establish the microanatomic relationships of the ciliary region with any modern degree of accuracy. Nonetheless, ancient authors, such as Galen and Rufus, clearly understood that the lens is located anteriorly. There is little reason to believe that Celsus or other ancient authors held a variant understanding of the anatomy of a healthy eye. The notion of the central location of the lens seems to have arisen with Arabic authors in 9th century Mesopotamia, and lasted for over 7 centuries
    • …
    corecore