Aristotle categories biology


Published on

Published in: Education
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Aristotle categories biology

  1. 1. An Introduction to the History of Science and Philosophy of Science THE LEGACY OF ARISTOTLE Part 1 Analyzing Reality
  2. 2. Aristotle (384 – 322 BCE)
  3. 3. <ul><li>This picture is often used to illustrate the central purpose of philosophy which is to see through the limitations of our own subjective viewpoints and appearances and to discover reality. </li></ul>
  4. 4. Why Start with Aristotle? <ul><ul><li>He pioneered such studies as biology (including dissection), physics, astronomy, meteorology and psychology. He developed them into specialized areas of study. For example, in biology he developed the first system of classifying living things by examining their physical characteristics; in physics, he examined the nature of motion, change, momentum; in psychology he studied the senses, dreams, sleep, memory, respiration; in meteorology he studied winds, weather patterns, evaporation, earth-quakes, tornadoes and lightning. In astronomy he developed the heliocentric concept of the universe that dominated western civilization for almost 2,000 years. He knew the earth was a sphere </li></ul></ul>
  5. 5. <ul><ul><li>1.2) He established many principles and axioms of scientific research that are still used today: </li></ul></ul><ul><ul><li>(a) The universe is an orderly place governed by rational laws, patterns and regularities. </li></ul></ul><ul><li>(b) If we observe nature and think correctly, we will learn something about reality itself. </li></ul><ul><li>(c) Research must be empirical, i.e. based on observations of phenomena. It must begin with induction. (d) Research must be systematic, i.e. organized and guided by rational principles of examination appropriate to the subject matter. </li></ul><ul><li>(e) Understanding and explaining phenomena means </li></ul><ul><li>developing causal explanations. </li></ul>
  6. 6. <ul><li>The second reason to begin with Aristotle is that he is also the first systematic philosopher. To Aristotle philosophy was not about expressing personal opinions but about studying the nature of reality at its most basic level. “ Philosophy consists in comprehending the reality of things as they exist, according to the capacity and the power of man,” ( Some Answered Questions , p. 221 .) </li></ul>
  7. 7. The Categories <ul><li>One of Aristotle’s most important books is “The Categories” in which he outlines the qualities that all physically sensible things have in common. Using the categories helps us to give order to our knowledge of the material world we live in. There are ten categories. As you read through these, imagine a cat: </li></ul><ul><li>1): Quantity : how much of something is there? 450 grams? How tall, wide, long is it? </li></ul><ul><li>2) : Quality : what qualities does something have? What </li></ul><ul><li>color? Texture? Shape? </li></ul><ul><li>3): Relation : how something relates to other things? Is it </li></ul>
  8. 8. <ul><ul><ul><li>cause? Effect? Friend? Enemy? Bigger ? Smaller? </li></ul></ul></ul><ul><ul><ul><li>Are things equivalent? </li></ul></ul></ul><ul><ul><ul><li>4) Place: where something is physically located in its environment. </li></ul></ul></ul><ul><ul><ul><li>5) When : when we observe something in time or its location in a time sequence. E.g. a parent exists before the child. A cat may be observed at 4 PM. </li></ul></ul></ul><ul><ul><ul><li>6) State/Condition : this refers to what something is </li></ul></ul></ul><ul><ul><ul><li>like for a limited period of time, e.g. the cat is sleeping, relaxed, hungry. It may also refer to what something is wearing or carrying, e.g. sandals, spear. </li></ul></ul></ul>
  9. 9. <ul><li>7): Position : this may also be understood as “pose” or “posture” of something, i.e. how it is related to its own parts. E.g. bent over, standing, sitting, twisted, leaning forward. </li></ul><ul><li>8): Action : how something affects something else, or </li></ul><ul><ul><li>what something is actually doing, e.g. running, writing </li></ul></ul><ul><ul><li>an essay, making me laugh, escaping from a dog. </li></ul></ul><ul><ul><li>9): Receptivity : how something is being affected by other things, e.g. being warmed by sunlight, being eaten by a cat, being planted by a farmer. </li></ul></ul><ul><ul><li>10) Substance : this is the most complex of Aristotle’s categories. The most important thing to remember is that ‘substance’ may only sometimes refers to physical ‘matter’ </li></ul></ul>
  10. 10. <ul><li>10.1): We will only be concerned with physically sensible and physically changeable substances that concern science. </li></ul><ul><li>10.2): Primary (first) substance : the individual things we perceive around us, e.g. a car, a fly, a rose, your mother or father. They are (a) separate from other things; (b) particular items; (c) numerically one. </li></ul><ul><li>10.2): Secondary substance : are ‘kinds of things’ to which particular things belong, e.g. human being (your mother); roses (the rose your boy/girlfriend gave you); horses (Black Beauty); rivers (Zayanderood). Every primary substance belongs to a secondary substance or class of things. A primary substance is always a particular example of a secondary substance (class). </li></ul>
  11. 11. <ul><li>10.3) Matter : sometimes ‘substance’ is used simply to refer to the physical matter of which things are made, e.g. paper, steel, cement, leather. </li></ul><ul><li>10.4): Substratum : sometimes ‘substance’ is used to mean the ‘stuff’ or substratum that endures through all changes; this stuff or substratum is neither created nor destroyed (see the conservation laws of physics). </li></ul><ul><li>*** Matter is one form of substratum. Elements e.g. gold or iron are already particular forms of it. Even the atomic particles – electrons, positrons, neutrons – are particular forms of the substratum. We cannot see just plain substratum. We always see a particular form of it. </li></ul><ul><li>*** Whenever we read or use the word ‘substance’ we must use the context to make sure which of these 4 possible meanings is meant. </li></ul>
  12. 12. <ul><li>THREE IMPORTANT PAIRS IN ARISTOTLE </li></ul><ul><li>Aristotle analyzes reality in terms of three other pairs of concepts that apply all things studied by science. </li></ul><ul><li>Matter and Form : every individual or primary substance studied by science has 2 aspects: matter and form. </li></ul><ul><li>*** Matter and form cannot be separated physically but they can be distinguished mentally. </li></ul><ul><li>*** Imagine a bronze statue. It has matter (bronze) from which it is made but also it also has form, the shape of a warrior, e.g. Achilles. </li></ul>
  13. 13. <ul><li>2): Actuality and Potentiality : The actuality of a thing is what the thing is right now, e.g. a baby rabbit, a part of a watch, a car, a river, a pen, my friend Max. The potentiality or possibility of a particular thing (primary substance) to change, i.e. to act or to be acted on (effected) by other things. E.g. a baby rabbit grows into an adult rabbit; my fat friend Max goes loses 20 kilos; 1500 kilos of steel are turned into a car. Each of them reaches a new actuality and reveals new possibilities. </li></ul><ul><li>*** All primary (individuals) and secondary (classes) substances are defined by their potentials/possibilities. A thing cannot change into something or do anything for which it lacks the potential(s). Pieces of iron do not grow up to be sunflowers. </li></ul><ul><li>*** Change is actualizing potentials, making them real. </li></ul>
  14. 14. <ul><li>3): Essential and Accidental Qualities: essential qualities or activities are necessary for a thing to be the kind of thing it is. E.g. a fish must be able to breathe in water; a triangle needs 3 sides; a car needs wheels; a house needs a roof; a computer needs a chip. </li></ul><ul><li>An accidental quality is one which is not necessary for a thing to be what it is. E.g. the color of a car does not stop it from being a car; the size of a rabbit does not stop it from being a rabbit; it doesn’t matter if a salad bowl is made of plastic or wood. </li></ul><ul><li>*** The essential/accidental distinction is important in everyday life. When you buy a boat you first look at essential attributes : Does it float? Does it have any leaks? Does the steering work? After that you look at non-essential or accidental qualities like color, or seat cushions, or a small fridge. </li></ul><ul><li>The last major concept in our survey of Aristotle is causality. </li></ul>
  15. 15. <ul><li>Concept of causality : In Some Answered Questions , Aristotle’s theory of causality is explained like this: </li></ul><ul><li>“ For the existence of everything depends upon four causes-- the efficient cause, the matter [material cause], the form [formal cause] and the final cause. For example, this chair has a maker who is a carpenter [the efficient cause] a substance [matter] which is wood [material cause], a form which is that of a chair, and a purpose [final cause] which is that it is to be used as a seat.” </li></ul><ul><li>*** In nature the efficient, formal and final causes operate as one; we cannot physically separate them although we can mentally distinguish them. </li></ul><ul><li>*** In nature, the final cause is the physical laws that make sure the efficient cause only acts in a certain way, e.g. that when sunlight falls on a chair, the chair gets warm – it does not turn into a rainbow. The final cause/physical law limits what the efficient cause can do. </li></ul><ul><li>*** The final cause makes sure efficient causes do not act randomly. </li></ul><ul><li>*** The final cause does not have to be conscious although, in the case of man, it is. </li></ul>
  16. 16. <ul><li>Applying What We Have Studied </li></ul>
  17. 17. <ul><li>The following questions apply the concepts covered in the previous slides. </li></ul><ul><li>#1: Pick any physical object in your room and describe it in terms of Aristotle’s first nine categories: quantity, quality, relation, place, time state/condition, position, action, receptivity. </li></ul><ul><ul><li>2.1: Why is what you chose a primary substance? </li></ul></ul><ul><ul><li>2.2: What is its secondary substance? </li></ul></ul><ul><ul><li>2.3: What kind of physical matter is it made of? </li></ul></ul><ul><ul><li># 2: Give a causal analysis of a house. What is the material cause? The efficient cause? The formal cause? The final cause? </li></ul></ul>
  18. 18. <ul><li>#3: Which of the following qualities is essential for a thing to be a car? Label essential qualities with an “E” and the accidental </li></ul>
  19. 19. <ul><li>qualities with an “A”: </li></ul><ul><ul><ul><li>- steering wheel </li></ul></ul></ul><ul><ul><ul><li>- leather covered seats </li></ul></ul></ul><ul><ul><ul><li>- brakes </li></ul></ul></ul><ul><ul><ul><li>- ash tray </li></ul></ul></ul><ul><ul><ul><li>- four doors </li></ul></ul></ul><ul><ul><ul><li>- color </li></ul></ul></ul><ul><ul><ul><li>- transmission </li></ul></ul></ul><ul><ul><ul><li>- electronic door opener </li></ul></ul></ul><ul><ul><ul><li>- gas pedal </li></ul></ul></ul><ul><ul><ul><li>However, if you were planning to buy a car to suit your personal preferences, you might think some “accidentals’ were actually “essential.” Which ones are essential now? </li></ul></ul></ul>
  20. 20. <ul><li># 4: Identify the primary substance with a “P” </li></ul><ul><li>(a) my dog Otto </li></ul><ul><li>(b) horses </li></ul><ul><li>(c) rocks </li></ul><ul><li>(d) my wife’s diamond </li></ul><ul><li>(e) flowers </li></ul><ul><li>(f) cars </li></ul><ul><li>(g) my car </li></ul><ul><li>(h) roses </li></ul><ul><li>(i) the rose on my table </li></ul>
  21. 21. <ul><li># 5: Take a blank piece of paper. What are 10 potentials ‘hidden’ in it, i.e. what can you change it into? </li></ul><ul><li># 6: Here is a mental exercise in discovering the unities hidden in diversities, i.e. the general features of reality. Choose two very different objects, e.g. a rose and a vase; a pen and an aspirin bottle. Find 10 ways in which they are alike. There are no wrong answers. </li></ul>
  22. 22. Aristotle’s Biology <ul><li>1: Aristotle’s greatest achievements as a scientist are in </li></ul><ul><li>biology. He directly studied almost 500 species including </li></ul><ul><li>land animals, birds, fish, marine mammals and </li></ul><ul><li>cephalopods. </li></ul><ul><li>His discoveries sometimes anticipated modern discoveries: </li></ul><ul><li>(a) Dolphins are sea mammals not fish. </li></ul><ul><li>(b) The distinction between homologous and analogous parts. </li></ul><ul><ul><li>– homologous : similarity due to shared ancestry e.g. the forelimbs in mammals; </li></ul></ul><ul><li>– analogous : organs that perform a similar function but evolved </li></ul><ul><ul><li>separately, e.g. wings of a maple seed an a bird’s wings. </li></ul></ul>
  23. 23. <ul><li>( c) Some sharks give birth to live young </li></ul><ul><li>(d) Some reef fish transform from female to male </li></ul><ul><li>(e) The Eustachian tube linking the middle ear to throat in humans </li></ul><ul><li>(f) The embryological development of chickens which he discovered in one of history’s first recorded experiments. </li></ul><ul><li>(g) The mating process of the octopus </li></ul><ul><li>2: Aristotle set out his program for biological research: </li></ul><ul><li>we should begin with observational, i.e. empirical evidence before developing causal explanations for what we see. </li></ul><ul><li>(b) he views biological phenomena as examples of final causes; we must explain parts of animals in terms of their purpose e.g. reproduction, defense, escape. “Everything that nature makes is a means towards an end [goal]” ( Parts of Animals , 1,1). He develops a teleological view of biology. </li></ul>
  24. 24. <ul><li>(c) empirical studies should be divided into (1) getting food; (2) actions; (3) habits; (4) bodily parts; (5) reproduction. </li></ul><ul><li>(d) in classifying kinds of creatures we must recognize “natural groups” on the basis of common (universal) essential attributes. Classifying should not break up “natural groups.” </li></ul><ul><li>(e) in classifying we should start with a large group (genus) of “proximate creatures” that seem generally similar and then identify particular species that fit into the genus </li></ul><ul><li>(f) One important aspect of his systematics was the “scala naturae,” i.e. the scale, ‘ladder,’ or hierarchy of nature. The underlying idea is, once again, that nature is orderly and, in regards to complexity, is arranged in a hierarchy. In general terms, the plant is the least complex and humans are most complex. </li></ul>
  25. 25. <ul><li>(g) Aristotle promoted experimentation. His discoveries about the development of chicks in the egg were made by observing how far the chicks were developed each day after the eggs were laid. </li></ul><ul><li>In classifying living things into types or categories, Aristotle was applying what he did with non-living things in “The Categories” to living things. He was showing there is an order in nature . </li></ul>
  26. 26. <ul><li>This arrangement was not improved until Linnaeus and Cuvier in the 18 th C CE. </li></ul><ul><li>BLOODED ANIMALS </li></ul><ul><ul><li>A: Bearing live young (viviparous) </li></ul></ul><ul><ul><ul><li>1: Man </li></ul></ul></ul><ul><ul><ul><li>2: others . . . including cetacea (sea mammals) </li></ul></ul></ul><ul><ul><li>B Egg Layers (oviparous) </li></ul></ul><ul><ul><ul><li>1: with perfect egg: Birds </li></ul></ul></ul><ul><ul><ul><li>2: scaly reptiles </li></ul></ul></ul><ul><ul><ul><li>3: with imperfect egg: fish, </li></ul></ul></ul>
  27. 27. <ul><ul><li>C. NON-BLOODED ANIMALS </li></ul></ul><ul><ul><ul><ul><li>1: non-shelled soft sea-animals: cephalopods, </li></ul></ul></ul></ul><ul><ul><ul><ul><li>2: soft-shelled sea animals: crustacea </li></ul></ul></ul></ul><ul><ul><ul><ul><li>3: Insects </li></ul></ul></ul></ul><ul><ul><ul><ul><li>4: Bees </li></ul></ul></ul></ul><ul><ul><li>D. VERMIPAROUS (spontaneous generation from slime etc.) </li></ul></ul><ul><ul><ul><ul><li>1: molluscs </li></ul></ul></ul></ul><ul><ul><ul><li>2: zoophytes (an animal that looks like a plant); e.g. sea anemone. </li></ul></ul></ul>
  28. 28. <ul><ul><ul><li>*** Aristotle recognized that there were intermediate species that were hard to classify, e,g. sea anemone. </li></ul></ul></ul><ul><ul><ul><li>*** He recognized that there was adaptation within species to accommodate the needs of the whole organism. </li></ul></ul></ul><ul><ul><ul><li>*** However he believed in the immutability of species, i.e. one species did not change into another since this would require a change of essence. This belief was not successfully challenged until Charles Darwin in the 19 th C CE. </li></ul></ul></ul><ul><ul><ul><li>*** Note that for Aristotle, human beings are physically parts of nature like all other kinds of being. In his view, humans are only distinguished by their rational soul. </li></ul></ul></ul>
  29. 29. <ul><ul><ul><ul><ul><li>Biology Questions </li></ul></ul></ul></ul></ul><ul><li>(1) Aristotle laid out many guidelines for doing biological research. Identify four of them and explain why in your opinion each of them is or is not useful today. </li></ul><ul><li>(2) Explain how Aristotle connected his studies in biology with his studies in analyzing reality in general. </li></ul>