This Unit's

History Lecture for Unit 11: Aristotle's Categories and Scientific Classification

For Class

Period: 350-280
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Geographic Location: Greece, Asia Minor
People to know: Aristotle, Theophrastus, Plato
See science topics: Classifying Vertebrates

Aristotle's contributions to Biology

We moved forward during the last two units in order to finish our discussion of basic concepts of matter and force, studying first the advances leading from Aristotle to Ptolemy's astronomy and the Almagest, written around 160 ce, and then summarizing the mechanical sciences developed by the Hellenist scientists and the Romans during the same period. Now we go back to Aristotle and look at the other major area of early Greek science: the study of biology and medicine. For the next three units, we will concentrate on Aristotle and Theophrastus' theories of life. Our science units will look at modern classification systems and the basic characteristics of vertebrate, invertebrate and plant organisms as we view them today.

Aristotle's Biography

This time, we'll take a look at the experiences which helped shape Aristotle's world view, and in particular, his ideas about scientific methods such as classification and observation.

In order to accomplish this concentrated study, we need to pay much closer attention to the life of the scientists and to their actual works. To learn about Aristotle's life, read The Ten Minute Aristotle by Prof. Cohen at the University of Washington.

What are Aristotle's dates? Where was he born? How did his place of birth influence his later life?
What did Aristotle study with Theophrastus on the island of Lesbos?
Who hired Aristotle to teach his own son? What happened to the son?
What school did Plato found in Athens?
How many of Aristotle's completed works do we have? What are they like?
How does Aristotle divide knowledge into branches?
What is a priori reasoning? Does Aristotle believe that all science is simply accomplished through this kind of approach?
What is the difference in the existence of "whiteness" and the existence of a horse?
What does Aristotle consider primary substance?
What is change?
What does qua mean?
What are the major characteristics of Aristotle's universe?
What parts of Aristotle's universe can change in substance? What parts do not change their substance (and die)?
Review the four kinds of cause. Do all things have all four causes? Can the formal cause and final cause be the same thing for a living organism?
What differentiates living and nonliving matter?
What differentiates humans from other kinds of animals?
According to Aristotle, is it possible to possess moral virtues without intellectual virtues? Why or why not?
How does Aristotle think politics and ethics are related?

Aristotle's Biology (Part I)

Aristotle had a lifelong interest in biology, which is evident from his many works that deal with animals. The classification of living things as a scientific discipline began with his investigations. Aristotle discusses the structure of over 540 different species, some in such detail that it is clear that Aristotle either performed or observed dissections. He also describes living habits which he could only have learned by direct observation.

Read about Aristotle's approach to the classification of animals parts 1-5 of his On the History of Animals, available at the MIT archives. [You may read as much as you like, but I'm only assigning parts 1-5 of book 1]. If you have your own English translation available, you can use that if you prefer.

Study/Discussion Questions:

As you read Aristotle's work on Animals, remember that this work was not polished and complete, ready for publication, but a set of notes that Aristotle used for his lectures. So they contain only the major points.

Consider these questions:

Aristotle starts by considering how to divide his topic into parts. What kinds of parts does he come up with?
How does Aristotle group animals according to where they live?
What does Aristotle mean by gregarious and solitary animals? What examples does he give of each?
What other characteristics does Aristotle consider as means of classifying animals into groups?
What are the characteristics common to all animals or to most animals?
What sense is common to all animals?
How do animals differ in their limbs?

Further Study/On Your Own

Andrea Marcogliese, a student in Greek Science at Tufts, has written a discussion of the methodology Aristotle uses to learn about teeth in The Biting Truth.
There is an excellent bibliography on Aristotle as a biologist at the University of Hawaii.

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Natural Science - Year I

Unit 11: Aristotle and Classification