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The human criterion for perfect vision is 20/20 for reading the standard lines on a Snellen eye chart without a hitch. The score is determined by how well you read lines of letters of different sizes from 20 feet away. But being able to read the bottom line on the eye chart does not approximate perfection as far as other species are concerned. Most birds would consider us very visually handicapped. The hawk, for instance, has such sharp eyes that it can spot a dime on the sidewalk while perched on top of the Empire State Building. It can make fine visual distinctions because it is blessed with one million cones per square millimeter in its retina. And in water, humans are farsighted, while the kingfisher, swooping down to spear fish, can see well in both the air and water because it is endowed with two foveae – areas of the eye, consisting mostly of cones, that provide visual distinctions. One foveae permits the bird, while in the air, to scan the water below with one eye at a time. This is called monocular vision. Once it hits the water, the other fovea joins in, allowing the kingfisher to focus both eyes, like binoculars, on its prey at the same time. A frog’s vision is distinguished by its ability to perceive things as a constant motion picture. Known as “bug detectors”, a highly developed set of cells in a frog’s eyes responds mainly to moving objects. So, it is said that a frog sitting in a field of dead bugs wouldn’t see them as food and would starve. The bee has a “compound” eye, which is used for navigation. It has 15,000 facets that divide what it sees into a pattern of dots, or mosaic. With this kind of vision, the bee sees the sun only as a single dot, a constant point of reference. Thus, the eye is a superb navigational instrument that constantly measures the angle of its line of flight in relation to the sun. A bee’s eye also gauges flight speed. And if that is not enough to leave our 20/20 “perfect vision” paling into insignificance, the bee is capable of seeing something we can’t – ultraviolet light. Thus, what humans consider to be “perfect vision” is in fact rather limited when we look at other species. However, there is still much to be said for the human eye. Of all the mammals, only humans and some primates can enjoy the pleasures of color vision. 26. What does the passage mainly discuss?
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According to the passage, pragmatism was more popular in America than Europe because
Philosophy in the second half of the 19th century was based more on biology and history than on mathematics and physics. Revolutionary thought drifted away from metaphysics and epistemology and shifted more towards ideologies in science, politics, and sociology. Pragmatism became the most vigorous school of thought in American philosophy during this time, and it continued the empiricist tradition of grounding knowledge on experience and stressing the inductive procedures of experimental science. The three most important pragmatists of this period were the American philosophers Charles Peirce (1839-1914), considered to be the first of the American pragmatists, William James (1842-1910), the first great American psychologist, and John Dewey (1859-1952), who further developed the pragmatic principles of Peirce and James into a comprehensive system of thought that he called “experimental naturalism”, or “instrumentalism”. Pragmatism was generally critical of traditional western philosophy, especially the notion that there are absolute truths and absolute values. In contrast, Josiah Royce (1855-1916), was a leading American exponent of idealism at this time, who believed in an absolute truth and held that human thought and the external world were unified. Pragmatism called for ideas and theories to be tested in practice, assessing whether they produced desirable or undesirable results. Although pragmatism was popular for a time in Europe, most agree that it epitomized the American faith in know-how and practicality, and the equally American distrust of abstract theories and ideologies. Pragmatism is best understood in its historical and cultural context. It arose during a period of rapid scientific advancement, industrialization, and material progress; a time when the theory of evolution suggested to many thinkers that humanity and society are in a perpetual state of progress. This period also saw a decline in traditional religious beliefs and values. As a result, it became necessary to rethink fundamental ideas about values, religion, science, community, and individuality. Pragmatists regarded all theories and institutions as tentative hypotheses and solutions. According to their critics, the pragmatist’s refusal to affirm any absolutes carried negative implications for society, challenging the foundations of society’s institutions. 16.What is this passage primarily about?
According to the passage , what was the function of the National Academy of Design for the painters born before 1835
The term "Hudson River school" was applied to the foremost representatives of nineteenth- century North American landscape painting. Apparently unknown during the golden days of the American landscape movement, which began around 1850 and lasted until the late 1860's, the Hudson River school seems to have emerged in the 1870's as a direct result of the struggle between the old and the new generations of artists, each to assert its own style as the representative American art. Theolder painters, most of whom were born before 1835, practiced in a mode often self-taught and monopolized by landscape subject matter and were securely established in and fostered by the reigning American art organization, the National Academy of Design. The younger painters returning home from training in Europe worked more with figural subject matter and in a bold and impressionistic technique; their prospects for patronage in their own country were uncertain, and they sought to attract it by attaining academic recognition in New York. One of the results of the conflict between the two factions was that what in previous years had been referred to as the "American", "native", or, occasionally, "New York" school — the most representative school of American art in any genre — had by 1890 become firmly established in the minds of critics and public alike as the Hudson River school. The sobriquet was first applied around 1879. While it was not intended as flattering, it was hardly inappropriate. The Academicians at whom it was aimed had worked and socialized in New York, the Hudson's port city, and had painted the river and its shores with varying frequency. Most important, perhaps, was that they had all maintained with a certain fidelity a manner of technique and composition consistent with those of America's first popular landscape artist, Thomas Cole,who built a career painting the Catskill Mountain scenery bordering the Hudson River. A possible implication in the term applied to the group of landscapists was that many of them had, like Cole,lived on or near the banks of the Hudson. Further, the river had long served as the principal route toother sketching grounds favored by the Academicians, particularly the Adirondacks and the mountains of Vermont and New Hampshire. 16. What does the passage mainly discuss
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