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  1. The human ear, like that of other mammals, contains sense organs that serve two quite different functions: that of hearing and that of postural equilibrium and coordination of head and eye movements. Anatomically, the ear has three distinguishable parts: the outer, middle, and inner ear.

  2. Large numbers are numbers above one million that are usually represented either with the use of an exponent such as 109 or by terms such as billion or thousand millions that frequently differ from system to system. The American system of numeration for denominations above one million was modeled on

    • The Editors of Encyclopaedia Britannica
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    Aristotle was one of the greatest philosophers who ever lived and the first genuine scientist in history. He made pioneering contributions to all fields of philosophy and science, he invented the field of formal logic, and he identified the various scientific disciplines and explored their relationships to each other. Aristotle was also a teacher and founded his own school in Athens, known as the Lyceum.

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    Where did Aristotle live?

    After his father died about 367 BCE, Aristotle journeyed to Athens, where he joined the Academy of Plato. He left the Academy upon Plato’s death about 348, traveling to the northwestern coast of present-day Turkey. He lived there and on the island of Lésbos until 343 or 342, when King Philip II of Macedonia summoned him to the Macedonian capital, Pella, to act as tutor to Philip’s young teenage son, Alexander, which he did for two or three years. Aristotle presumably lived somewhere in Macedonia until his (second) arrival in Athens in 335. In 323 hostility toward Macedonians in Athens prompted Aristotle to flee to the island of Euboea, where he died the following year.

    Aristotle was born on the Chalcidic peninsula of Macedonia, in northern Greece. His father, Nicomachus, was the physician of Amyntas III (reigned c. 393–c. 370 bce), king of Macedonia and grandfather of Alexander the Great (reigned 336–323 bce). After his father’s death in 367, Aristotle migrated to Athens, where he joined the Academy of Plato (c. 428–c. 348 bce). He remained there for 20 years as Plato’s pupil and colleague.

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    Many of Plato’s later dialogues date from these decades, and they may reflect Aristotle’s contributions to philosophical debate at the Academy. Some of Aristotle’s writings also belong to this period, though mostly they survive only in fragments. Like his master, Aristotle wrote initially in dialogue form, and his early ideas show a strong Platonic influence. His dialogue Eudemus, for example, reflects the Platonic view of the soul as imprisoned in the body and as capable of a happier life only when the body has been left behind. According to Aristotle, the dead are more blessed and happier than the living, and to die is to return to one’s real home.

    Another youthful work, the Protrepticus (“Exhortation”), has been reconstructed by modern scholars from quotations in various works from late antiquity. Everyone must do philosophy, Aristotle claims, because even arguing against the practice of philosophy is itself a form of philosophizing. The best form of philosophy is the contemplation of the universe of nature; it is for this purpose that God made human beings and gave them a godlike intellect. All else—strength, beauty, power, and honour—is worthless.

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    When Plato died about 348, his nephew Speusippus became head of the Academy, and Aristotle left Athens. He migrated to Assus, a city on the northwestern coast of Anatolia (in present-day Turkey), where Hermias, a graduate of the Academy, was ruler. Aristotle became a close friend of Hermias and eventually married his ward Pythias. Aristotle helped Hermias to negotiate an alliance with Macedonia, which angered the Persian king, who had Hermias treacherously arrested and put to death about 341. Aristotle saluted Hermias’s memory in “Ode to Virtue,” his only surviving poem.

    While in Assus and during the subsequent few years when he lived in the city of Mytilene on the island of Lesbos, Aristotle carried out extensive scientific research, particularly in zoology and marine biology. This work was summarized in a book later known, misleadingly, as The History of Animals, to which Aristotle added two short treatises, On the Parts of Animals and On the Generation of Animals. Although Aristotle did not claim to have founded the science of zoology, his detailed observations of a wide variety of organisms were quite without precedent. He—or one of his research assistants—must have been gifted with remarkably acute eyesight, since some of the features of insects that he accurately reports were not again observed until the invention of the microscope in the 17th century.

    The scope of Aristotle’s scientific research is astonishing. Much of it is concerned with the classification of animals into genus and species; more than 500 species figure in his treatises, many of them described in detail. The myriad items of information about the anatomy, diet, habitat, modes of copulation, and reproductive systems of mammals, reptiles, fish, and insects are a melange of minute investigation and vestiges of superstition. In some cases his unlikely stories about rare species of fish were proved accurate many centuries later. In other places he states clearly and fairly a biological problem that took millennia to solve, such as the nature of embryonic development.

    Despite an admixture of the fabulous, Aristotle’s biological works must be regarded as a stupendous achievement. His inquiries were conducted in a genuinely scientific spirit, and he was always ready to confess ignorance where evidence was insufficient. Whenever there is a conflict between theory and observation, one must trust observation, he insisted, and theories are to be trusted only if their results conform with the observed phenomena.

  3. As the head of the government of the United States, the president is arguably the most powerful government official in the world. The president is elected to a four-year term via an electoral college system. Since the Twenty-second Amendment was adopted in 1951, the American presidency has been

  4. list of countries. Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors. This is an alphabetically ordered list of the ...

  5. 2024年4月18日 · David Bevington. Macbeth, tragedy in five acts by William Shakespeare, written sometime in 1606–07 and published in the First Folio of 1623. The play chronicles Macbeth’s seizing of power and subsequent destruction, both his rise and his fall the result of blind ambition.

  6. The United Kingdom is a constitutional monarchy, in which the monarch shares power with a constitutionally organized government. The reigning king or queen is the country’s head of state. All political power rests with the prime minister (the head of government) and the cabinet, and the monarch must act on their advice.