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1 Archimedes of Syracuse
[br]b. 287 BCd. 212 BC[br]Greek engineer who made the first measurement of specific gravity.[br]He studied in Alexandria, after which he returned to Syracuse where he spent most of the rest of his life. He made many mathematical discoveries, including the most accurate calculation of pi made up to that time. In engineering he was the founder of the science of hydrostatics. He is well known for the discovery of "Archimedes" Law', that a body wholly or partly immersed in a fluid loses weight equal to the weight of the fluid displaced. He thus made the first measurement of specific gravity.Archimedes also proved the law of the lever and developed the theory of mechanical advantage, boasting to his cousin Hieron, "Give me a place to stand on and with a lever I will move the whole world." To prove his point, he launched one of the biggest ships built up to that date. During his time in Egypt, he devised the "Archimedean Screw", still used today in Middle Eastern countries for pumping water. He also built an astronomical instrument to demonstrate the movements of the heavenly bodies, a form of orrery.He was General of Ordnance to Heiron, and when the Romans besieged Syracuse, a legionary came across Archimedes drawing geometrical diagrams in the sand. Archimedes immediately told him to 'Keep off and the soldier killed him. He also experimented with burning glasses and mirrors for setting fire to wooden ships.[br]Further ReadingL.Sprague de Camp, 1963, Ancient Engineers, Souvenir Press. E.J.Dijksterhuis, 1956, Archimedes, Copenhagen: Munksgaard.IMcN -
2 Syracuse, Archimedes of
Biographical history of technology > Syracuse, Archimedes of
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3 Psychology
We come therefore now to that knowledge whereunto the ancient oracle directeth us, which is the knowledge of ourselves; which deserveth the more accurate handling, by how much it toucheth us more nearly. This knowledge, as it is the end and term of natural philosophy in the intention of man, so notwithstanding it is but a portion of natural philosophy in the continent of nature.... [W]e proceed to human philosophy or Humanity, which hath two parts: the one considereth man segregate, or distributively; the other congregate, or in society. So as Human philosophy is either Simple and Particular, or Conjugate and Civil. Humanity Particular consisteth of the same parts whereof man consisteth; that is, of knowledges which respect the Body, and of knowledges that respect the Mind... how the one discloseth the other and how the one worketh upon the other... [:] the one is honored with the inquiry of Aristotle, and the other of Hippocrates. (Bacon, 1878, pp. 236-237)The claims of Psychology to rank as a distinct science are... not smaller but greater than those of any other science. If its phenomena are contemplated objectively, merely as nervo-muscular adjustments by which the higher organisms from moment to moment adapt their actions to environing co-existences and sequences, its degree of specialty, even then, entitles it to a separate place. The moment the element of feeling, or consciousness, is used to interpret nervo-muscular adjustments as thus exhibited in the living beings around, objective Psychology acquires an additional, and quite exceptional, distinction. (Spencer, 1896, p. 141)Kant once declared that psychology was incapable of ever raising itself to the rank of an exact natural science. The reasons that he gives... have often been repeated in later times. In the first place, Kant says, psychology cannot become an exact science because mathematics is inapplicable to the phenomena of the internal sense; the pure internal perception, in which mental phenomena must be constructed,-time,-has but one dimension. In the second place, however, it cannot even become an experimental science, because in it the manifold of internal observation cannot be arbitrarily varied,-still less, another thinking subject be submitted to one's experiments, comformably to the end in view; moreover, the very fact of observation means alteration of the observed object. (Wundt, 1904, p. 6)It is [Gustav] Fechner's service to have found and followed the true way; to have shown us how a "mathematical psychology" may, within certain limits, be realized in practice.... He was the first to show how Herbart's idea of an "exact psychology" might be turned to practical account. (Wundt, 1904, pp. 6-7)"Mind," "intellect," "reason," "understanding," etc. are concepts... that existed before the advent of any scientific psychology. The fact that the naive consciousness always and everywhere points to internal experience as a special source of knowledge, may, therefore, be accepted for the moment as sufficient testimony to the rights of psychology as science.... "Mind," will accordingly be the subject, to which we attribute all the separate facts of internal observation as predicates. The subject itself is determined p. 17) wholly and exclusively by its predicates. (Wundt, 1904,The study of animal psychology may be approached from two different points of view. We may set out from the notion of a kind of comparative physiology of mind, a universal history of the development of mental life in the organic world. Or we may make human psychology the principal object of investigation. Then, the expressions of mental life in animals will be taken into account only so far as they throw light upon the evolution of consciousness in man.... Human psychology... may confine itself altogether to man, and generally has done so to far too great an extent. There are plenty of psychological text-books from which you would hardly gather that there was any other conscious life than the human. (Wundt, 1907, pp. 340-341)The Behaviorist began his own formulation of the problem of psychology by sweeping aside all medieval conceptions. He dropped from his scientific vocabulary all subjective terms such as sensation, perception, image, desire, purpose, and even thinking and emotion as they were subjectively defined. (Watson, 1930, pp. 5-6)According to the medieval classification of the sciences, psychology is merely a chapter of special physics, although the most important chapter; for man is a microcosm; he is the central figure of the universe. (deWulf, 1956, p. 125)At the beginning of this century the prevailing thesis in psychology was Associationism.... Behavior proceeded by the stream of associations: each association produced its successors, and acquired new attachments with the sensations arriving from the environment.In the first decade of the century a reaction developed to this doctrine through the work of the Wurzburg school. Rejecting the notion of a completely self-determining stream of associations, it introduced the task ( Aufgabe) as a necessary factor in describing the process of thinking. The task gave direction to thought. A noteworthy innovation of the Wurzburg school was the use of systematic introspection to shed light on the thinking process and the contents of consciousness. The result was a blend of mechanics and phenomenalism, which gave rise in turn to two divergent antitheses, Behaviorism and the Gestalt movement. The behavioristic reaction insisted that introspection was a highly unstable, subjective procedure.... Behaviorism reformulated the task of psychology as one of explaining the response of organisms as a function of the stimuli impinging upon them and measuring both objectively. However, Behaviorism accepted, and indeed reinforced, the mechanistic assumption that the connections between stimulus and response were formed and maintained as simple, determinate functions of the environment.The Gestalt reaction took an opposite turn. It rejected the mechanistic nature of the associationist doctrine but maintained the value of phenomenal observation. In many ways it continued the Wurzburg school's insistence that thinking was more than association-thinking has direction given to it by the task or by the set of the subject. Gestalt psychology elaborated this doctrine in genuinely new ways in terms of holistic principles of organization.Today psychology lives in a state of relatively stable tension between the poles of Behaviorism and Gestalt psychology.... (Newell & Simon, 1963, pp. 279-280)As I examine the fate of our oppositions, looking at those already in existence as guide to how they fare and shape the course of science, it seems to me that clarity is never achieved. Matters simply become muddier and muddier as we go down through time. Thus, far from providing the rungs of a ladder by which psychology gradually climbs to clarity, this form of conceptual structure leads rather to an ever increasing pile of issues, which we weary of or become diverted from, but never really settle. (Newell, 1973b, pp. 288-289)The subject matter of psychology is as old as reflection. Its broad practical aims are as dated as human societies. Human beings, in any period, have not been indifferent to the validity of their knowledge, unconcerned with the causes of their behavior or that of their prey and predators. Our distant ancestors, no less than we, wrestled with the problems of social organization, child rearing, competition, authority, individual differences, personal safety. Solving these problems required insights-no matter how untutored-into the psychological dimensions of life. Thus, if we are to follow the convention of treating psychology as a young discipline, we must have in mind something other than its subject matter. We must mean that it is young in the sense that physics was young at the time of Archimedes or in the sense that geometry was "founded" by Euclid and "fathered" by Thales. Sailing vessels were launched long before Archimedes discovered the laws of bouyancy [ sic], and pillars of identical circumference were constructed before anyone knew that C IID. We do not consider the ship builders and stone cutters of antiquity physicists and geometers. Nor were the ancient cave dwellers psychologists merely because they rewarded the good conduct of their children. The archives of folk wisdom contain a remarkable collection of achievements, but craft-no matter how perfected-is not science, nor is a litany of successful accidents a discipline. If psychology is young, it is young as a scientific discipline but it is far from clear that psychology has attained this status. (Robinson, 1986, p. 12)Historical dictionary of quotations in cognitive science > Psychology
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4 Hero of Alexandria
SUBJECT AREA: Architecture and building, Mechanical, pneumatic and hydraulic engineering, Photography, film and optics, Steam and internal combustion engines[br]fl. c.62 AD Alexandria[br]Alexandrian mathematician and mechanician.[br]Nothing is known of Hero, or Heron, apart from what can be gleaned from the books he wrote. Their scope and style suggest that he was a teacher at the museum or the university of Alexandria, writing textbooks for his students. The longest book, and the one with the greatest technological interest, is Pneumatics. Some of its material is derived from the works of the earlier writers Ctesibius of Alexandria and Philo of Byzantium, but many of the devices described were invented by Hero himself. The introduction recognizes that the air is a body and demonstrates the effects of air pressure, as when air must be allowed to escape from a closed vessel before water can enter. There follow clear descriptions of a variety of mechanical contrivances depending on the effects of either air pressure or heated gases. Most of the devices seem trivial, but such toys or gadgets were popular at the time and Hero is concerned to show how they work. Inventions with a more serious purpose are a fire pump and a water organ. One celebrated gadget is a sphere that is set spinning by jets of steam—an early illustration of the reaction principle on which modern jet propulsion depends.M echanics, known only in an Arabic version, is a textbook expounding the theory and practical skills required by the architect. It deals with a variety of questions of mechanics, such as the statics of a horizontal beam resting on vertical posts, the theory of the centre of gravity and equilibrium, largely derived from Archimedes, and the five ways of applying a relatively small force to exert a much larger one: the lever, winch, pulley, wedge and screw. Practical devices described include sledges for transporting heavy loads, cranes and a screw cutter.Hero's Dioptra describes instruments used in surveying, together with an odometer or device to indicate the distance travelled by a wheeled vehicle. Catoptrics, known only in Latin, deals with the principles of mirrors, plane and curved, enunciating that the angle of incidence is equal to that of reflection. Automata describes two forms of puppet theatre, operated by strings and drums driven by a falling lead weight attached to a rope wound round an axle. Hero's mathematical work lies in the tradition of practical mathematics stretching from the Babylonians through Islam to Renaissance Europe. It is seen most clearly in his Metrica, a treatise on mensuration.Of all his works, Pneumatics was the best known and most influential. It was one of the works of Greek science and technology assimilated by the Arabs, notably Banu Musa ibn Shakir, and was transmitted to medieval Western Europe.[br]BibliographyAll Hero's works have been printed with a German translation in Heronis Alexandrini opera quae supersunt omnia, 1899–1914, 5 vols, Leipzig. The book on pneumatics has been published as The Pneumatics of Hero of Alexandria, 1851, trans. and ed. Bennet Wood-croft, London (facs. repr. 1971, introd. Marie Boas Hall, London and New York).Further ReadingA.G.Drachmann, 1948, "Ktesibios, Philon and Heron: A Study in Ancient Pneumatics", Acta Hist. Sci. Nat. Med. 4, Copenhagen: Munksgaard.T.L.Heath, 1921, A History of Greek Mathematics, Oxford (still useful for his mathematical work).LRD -
5 Mechanical, pneumatic and hydraulic engineering
See also: INDEX BY SUBJECT AREA[br]Clement, JosephDu ShiDu YuGongshu PanLi BingMa JunMurdock, WilliamSomerset, EdwardBiographical history of technology > Mechanical, pneumatic and hydraulic engineering
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6 Ports and shipping
See also: INDEX BY SUBJECT AREA[br]Armstrong, Sir William GeorgeEgerton, FrancisLi GaoPeter the GreatShen GuaStanhope, Charles -
7 Smith, Sir Francis Pettit
SUBJECT AREA: Ports and shipping[br]b. 9 February 1808 Copperhurst Farm, near Hythe, Kent, Englandd. 12 February 1874 South Kensington, London, England[br]English inventor of the screw propeller.[br]Smith was the only son of Charles Smith, Postmaster at Hythe, and his wife Sarah (née Pettit). After education at a private school in Ashford, Kent, he took to farming, first on Romney Marsh, then at Hendon, Middlesex. As a boy, he showed much skill in the construction of model boats, especially in devising their means of propulsion. He maintained this interest into adult life and in 1835 he made a model propelled by a screw driven by a spring. This worked so well that he became convinced that the screw propeller offered a better method of propulsion than the paddle wheels that were then in general use. This notion so fired his enthusiasm that he virtually gave up farming to devote himself to perfecting his invention. The following year he produced a better model, which he successfully demonstrated to friends on his farm at Hendon and afterwards to the public at the Adelaide Gallery in London. On 31 May 1836 Smith was granted a patent for the propulsion of vessels by means of a screw.The idea of screw propulsion was not new, however, for it had been mooted as early as the seventeenth century and since then several proposals had been advanced, but without successful practical application. Indeed, simultaneously but quite independently of Smith, the Swedish engineer John Ericsson had invented the ship's propeller and obtained a patent on 13 July 1836, just weeks after Smith. But Smith was completely unaware of this and pursued his own device in the belief that he was the sole inventor.With some financial and technical backing, Smith was able to construct a 10 ton boat driven by a screw and powered by a steam engine of about 6 hp (4.5 kW). After showing it off to the public, Smith tried it out at sea, from Ramsgate round to Dover and Hythe, returning in stormy weather. The screw performed well in both calm and rough water. The engineering world seemed opposed to the new method of propulsion, but the Admiralty gave cautious encouragement in 1839 by ordering that the 237 ton Archimedes be equipped with a screw. It showed itself superior to the Vulcan, one of the fastest paddle-driven ships in the Navy. The ship was put through its paces in several ports, including Bristol, where Isambard Kingdom Brunel was constructing his Great Britain, the first large iron ocean-going vessel. Brunel was so impressed that he adapted his ship for screw propulsion.Meanwhile, in spite of favourable reports, the Admiralty were dragging their feet and ordered further trials, fitting Smith's four-bladed propeller to the Rattler, then under construction and completed in 1844. The trials were a complete success and propelled their lordships of the Admiralty to a decision to equip twenty ships with screw propulsion, under Smith's supervision.At last the superiority of screw propulsion was generally accepted and virtually universally adopted. Yet Smith gained little financial reward for his invention and in 1850 he retired to Guernsey to resume his farming life. In 1860 financial pressures compelled him to accept the position of Curator of Patent Models at the Patent Museum in South Kensington, London, a post he held until his death. Belated recognition by the Government, then headed by Lord Palmerston, came in 1855 with the grant of an annual pension of £200. Two years later Smith received unofficial recognition when he was presented with a national testimonial, consisting of a service of plate and nearly £3,000 in cash subscribed largely by the shipbuilding and engineering community. Finally, in 1871 Smith was honoured with a knighthood.[br]Principal Honours and DistinctionsKnighted 1871.Further ReadingObituary, 1874, Illustrated London News (7 February).1856, On the Invention and Progress of the Screw Propeller, London (provides biographical details).Smith and his invention are referred to in papers in Transactions of the Newcomen Society, 14 (1934): 9; 19 (1939): 145–8, 155–7, 161–4, 237–9.LRDBiographical history of technology > Smith, Sir Francis Pettit
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8 Truth
1) I Am, I Exist, Is Necessarily TrueArchimedes used to demand just one firm and immovable point in order to shift the entire earth; so I too can hope for great things if I manage to find just one thing, however slight, that is certain and unshakeable. I will suppose then, that everything is spurious. I will believe that my memory tells me lies, and that none of the things that it reports ever happened. I have no senses. Body, shape, extension, movement and place are chimeras. So what remains true? Perhaps just the fact that nothing is certain.Yet apart from everything I have just listed, how do I know that there is not something else which does not allow even the slightest occasion for doubt? Is there not a God, or whatever I may call him, who puts into me the thoughts I am now having? But why do I think this, since I myself may perhaps be the author of these thoughts? In that case am not I, at least, something? But I have just said that I have no senses and no body. This is the sticking point: what follows from this? Am I not so bound up with a body and with senses that I cannot exist without them? But I convinced myself that there is absolutely nothing in the world, no sky, no earth, no minds, no bodies. Does it now follow that I too do not exist?No: if I convinced myself of something then I certainly existed.... So after considering everything very thoroughly, I must finally conclude that this proposition, I am, I exist, is necessarily true whenever it is put forward by me or conceived in my mind. (Descartes, 1984, pp. 16-17)It would be an error to suppose that the great discoverer seizes at once upon the truth, or has any unerring method of divining it. In all probability the errors of the great mind exceed in number those of the less vigorous one. Fertility of imagination and abundance of guesses at truth are among the first requisites of discovery; but the erroneous guesses must be many times as numerous as those that prove well founded. The weakest analogies, the most whimsical notations, the most apparently absurd theories, may pass through the teeming brain, and no record remain of more than the hundredth part. (Jevons, 1900, p. 577)Historical dictionary of quotations in cognitive science > Truth
См. также в других словарях:
Archimedes — Archimedes, Domenico Fetti, 1620, Gemäldegalerie Alte Meister, Dresden Archimedes (griechisch ᾿Αρχιμήδης) von Syrakus (* um 287 v. Chr. vermutlich in Syrakus auf Sizilien; † 212 v. Chr. ebenda) war ein antiker griechischer … Deutsch Wikipedia
Archimedes — Archimedes, griechischer Mathematiker und Mechaniker, * Syrakus um 285 v. Chr., 212 v. Chr. bei der Eroberung von Syrakus von einem römischen Soldaten getötet. Nach dem Studium in Alexandria (um 245) behielt er, nach Syrakus zurückgekehrt,… … Universal-Lexikon
ARCHIMEDES — Syracusanus geometra; Cardano l. 16. Subtil. inimitabilis dictus, saepenumero invitus ad balnea ductus, dum perungendus in craterem constitueretur, per corporis unguenta, figuras ac lineamenta digito inscribebat. Plut. in Marcel. Cicer. l. 1.… … Hofmann J. Lexicon universale
Archimedes — Ar chi*me des, n. (Paleon.) An extinct genus of Bryzoa characteristic of the subcarboniferous rocks. Its form is that of a screw. [1913 Webster] … The Collaborative International Dictionary of English
Archimēdes — Archimēdes, griechischer Mathematiker aus Syrakus,[671] geb. 287 v. Chr., fand zuerst sehr genau das Verhältniß des Durchmessers des Kreises zu dessen Umfang u. der Kugel zum Cylinder u. Kegel, berechnete die Kreisfläche, beschäftigte sich auch… … Pierer's Universal-Lexikon
Archimēdes — Archimēdes, Pseudonym von Sprengseifen … Pierer's Universal-Lexikon
Archimēdes — Archimēdes. Mathematiker und Physiker, um 287 bis 212 v. Chr., aus Syrakus, lebte, abgesehen von einem Aufenthalt in Ägypten, in seiner Vaterstadt den Wissenschaften und ihrer Anwendung auf die Praxis. Seine kunstreichen Kriegsmaschinen… … Meyers Großes Konversations-Lexikon
Archimedes — Archimēdes, Mathematiker und Physiker des Altertums, geb. um 287 v. Chr. zu Syrakus, bereicherte die Mathematik und Physik mit wichtigen Entdeckungen (Bestimmung des Verhältnisses von Kegel, Halbkugel und Zylinder zueinander, Begründung der… … Kleines Konversations-Lexikon
Archimedes — Archimedes, geboren um 287 v. Chr. in Syrakus aus sehr vornehmer Familie, einer der größten Mathematiker und Physiker aller Zeiten. Er bestimmte das Verhältniß des Kreisdurchmessers zum Umfange, das Verhältniß zwischen Kugel, Cylinder und Kegel,… … Herders Conversations-Lexikon
Archimedes — [är΄kə mē′dēz΄] 287? 212 B.C.; Gr. mathematician & inventor, born in Syracuse (Sicily) Archimedean [är΄kə mē′dē ən, är΄kə mi dē′ən] adj … English World dictionary
Archimedes — For other uses, see Archimedes (disambiguation). Archimedes of Syracuse (Greek: Ἀρχιμήδης) … Wikipedia