The Most Influential
People in History
Aristotle / AHR-uh-stawt-uul /
384–322 B.C.E.
Greek Philosopher and Scientist
Mathematics Ranking 19th of 46
Overall Ranking 10th of 500
The young Aristotle on the right with the elderly Plato on the left. The central image of Raphael’s painting The School of Athens. Greek stamp from 1978.
Aristotle was a Greek systematic thinker who can be labeled a philosopher, and a scientist in almost every field. “He, more than any other thinker, determined the orientation and the content of Western intellectual history.”(1) Aristotle was the author of a philosophical and scientific system that through the centuries became the support and vehicle for both medieval Christian and Islamic scholastic thought.”(2) Until the end of the seventeenth century, Western culture was Aristotelian. Even after the intellectual revolutions of centuries to follow, Aristotelian concepts and ideas remained embedded in Western thinking.
Aristotle’s intellectual range was vast, covering most of the sciences and many of the arts. He worked in mathematics, physics, chemistry, biology, zoology, and botany; in psychology, political theory, and ethics; in logic and metaphysics; in history, literary theory, and rhetoric. Overall, Aristotle’s work constitutes the ancient world’s greatest encyclopedia.(3) His importance as a scientist is unparalleled. His greatest achievements were in two unrelated areas: He invented the study of formal logic, devising a finished system, known as Aristotelian syllogistic, that for centuries was regarded as the sum of logic. Second, he pioneered the study of zoology, both observational and theoretical, in which his work was not surpassed until the nineteenth century. This section discusses his work in logic while the section on Living Sciences/Medicine covers his work in zoology and the section on Literature covers his work in literary theory.
Bio
His father, Nicomachus, was the court physician to Amyntas III, king of Macedonia, father of Philip II, and grandfather of Alexander the Great. As a doctor’s son, Aristotle was heir to a scientific tradition some 200 years old. The case histories contained in the Epidemics of Hippocrates, the father of Greek medicine, may have introduced him at an early age to the concepts and practices of Greek medicine and biology. Because medicine was a traditional occupation in certain families, being handed down from father to son, Aristotle in all likelihood learned at home the fundamentals of that practical skill he was afterward to display in his biological researches. However, both parents died while Aristotle was a boy, and his knowledge of human anatomy and physiology remained a notably weak part in his biology.(4)
For twenty years, from ages 17–37, he attended Plato’s Academy at Athens. In 335 B.C.E., when he was 49, he established his own school or Lyceum just outside Athens. For the next twelve years, he coordinated the work of a number of scholars, turning his school into a center for speculation and research in every field of inquiry. Aristotle gave lectures on a wide range of scientific and philosophical questions. At one point, he tutored Alexander the Great. The chief difference between his school and Plato’s Academy was the scientific interest of the Platonists centered on mathematics, whereas the main contributions of Aristotle’s Lyceum were in biology and history.
In 323 B.C.E., Alexander the Great died and a brief but vigorous anti-Macedonian agitation broke out in Athens. Aristotle was a friend of Antipater, the Macedonian regent of Athens, and felt himself in danger. He therefore left Athens and went to his mother’s estates in Chalcis on the island of Euboea. He died the following year from a stomach illness at age 62 or 63.(5)
Mathematics–Logic
His thirty surviving written works fill about 2,000 pages and build from a base on logic called Logic or “Organon” (250 pages) in which he systematically creates a precise, logical foundation. For Aristotle, logic is treated as a preliminary to the study of each and every branch of knowledge.(6) Aristotle’s system of logic, called syllogistic logic, was the first deductive system in the history of logic,(7) though his syllogistic is now recognized as only a small part of formal logic. He developed his syllogistic (deductive) system in his Prior Analytics (58 pages). It appears Aristotle was the first to engage in the systematic, sustained investigation of inference in its own right.(8) He served as the cornerstone in the development of logic and, as Aristotle said, “logic was a tool used by all the sciences.”
A very important distinction in logic is the difference between deductive and inductive. Aristotle was a pioneer in deductive logic through his syllogistic system, wherein arguments could be recognized as valid or invalid. His form of reasoning took two given, or assumed, propositions (premises) from which a conclusion is drawn.
In general, the Greeks were the first to use deductive logic in a systematic way. The if-then statements encountered in a high school geometry class are examples of deductive reasoning or arguments used to reach new conclusions. The “if’ part of an “if-then” statement is called the hypothesis and the “then” part is called the conclusion. Aristotle also used inductive logic, or inductive arguments. However, what Aristotle wrote about induction was far briefer and much less systematic than what he wrote about deduction.(9) Much later, Galileo in the 1600s began using scientific inductive logic combined with exact measurement of his observations, which was the true beginning of modern scientific investigation.
The difference between deductive and inductive logic is subtle. Basically, a deductive method begins with certain axioms that are accepted without question, and conclusions are deduced. Inductive arguments, by contrast, make no assumption that the original hypothesis could be wrong. As data is gathered, the hypothesis is constantly tested for validity. There is never a point where the hypothesis cannot be invalidated. In practice, however, certain hypotheses become accepted because their validity has withstood countless tests. Newton’s laws of motion generally hold true in any situation and so have acquired the label “laws.”
The major task of logic is to establish a systematic way of deducing the logical consequences of a set of sentences. From its very beginning, the field of logic has been occupied with arguments in which certain statements, the premises, are asserted in order to support some other statement, the conclusion. If the premises are intended to provide conclusive support for the conclusion, the argument is a deductive one. If the premises are intended to support the conclusion only to a lesser degree, the argument is called inductive.
The Greeks’ deductive method is a form of formal logic which is a priori (made before or without examination and not supported by factual study), and not an empirical study. It contrasts with the natural sciences and with all other disciplines that use inductive reasoning and depend on observation for their data.(10) To reason inductively, you draw conclusions based on your observations. In inductive reasoning, you look at a few of the items in a group of items and then draw a conclusion about all the items in the group. That is, you use a few specific examples to help you come up with a generalization.(11) Deductive reasoning is the opposite in the sense that you begin with a generalization and derive specific conclusions, sometimes called theorems.
Conclusion
The insights produced by his work on logic were powerful tools he used to analyze/explore a wide range of fields, including astronomy, biology, zoology, chemistry, physics, psychology, ethics, philosophy, poetry, history, and political science. The detailed, logical, and comprehensive work he did in those fields was profoundly influential for many later thinkers in many fields worldwide, including the mathematicians Euclid (c. 300 B.C.E.) and Ptolemy (c. 100), the philosopher and scientist Avicenna (c. 1000), the theologian Thomas Aquinas (1200s), and the evolutionary biologist Charles Darwin (1800s). Aristotle’s approach of using empirical observation with logical reasoning to form conclusions, i.e., the beginnings of the scientific method, established the way almost all later scientists conducted their research.
Footnotes:
(1) Encyclopaedia Britannica, Macropaedia, Volume 14, 1993, 15th Edition, p. 55.
(2) Ibid., p. 55.
(3) Encyclopaedia Britannica, Macropaedia, Volume 25, 1993, 15th Edition, p. 563.
(4) C.C. Gillispie (Editor), Dictionary of Scientific Biography, Volume 1 (Chicago, 1981), p. 250.
(5) Encyclopaedia Britannica, Macropaedia, Volume 14, 1993, 15th Edition, p. 57.
(6) Ibid., p. 60.
(7) Encyclopaedia Britannica, Macropaedia, Volume 23, 1993, 15th Edition, p. 263.
(8) Ibid., p. 262.
(9) Jonathan Barnes (Editor), The Cambridge Companion to Aristotle (Cambridge: Cambridge University Press, 1995), p. 32.
(10) Ibid., p. 230.
(11) Alan Wise, Introductory Geometry -- A Brief Course with Reasoning Skills (New York, 1990), p. 5.
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