Chaos vs. Order: Aristotle and Linnaeus Jonathan Bastian Phil 223: History of Science & Metaphysics with Dr. Griffith axonomy is man’s attempt to understand his method against modern methods and sci- Tthe organizational structure of living organ- ence. No one can fully understand another isms. It originates from the idea that there is a person’s thought process, and therefore, we supreme being who created everything and, cannot make assumptions regarding a phi- therefore, a perfect organization to living or- losopher’s methods. Yet, if there is a desire, ganisms must exist. With their own distinct whether out of necessity or pure casual inter- opinions on how organisms should be classi- est, to understand the development of mod- fied, philosophers and scientists alike have at- ern science, one must look at and analyze tempted to make the perfect arrangement the ideas and beliefs of the first scientists--phi- of organisms. These methods are all derived losophers or others--to the best of our ability. from previous methods; hence, we must look Whether modern science confirms it or dis- at Aristotle and Linnaeus for guidance and to putes it, all modern conclusions and scientific compare what they thought to what mod- philosophies have been influenced by those ern science appears to tell us regarding the earliest thinkers. relationship between organisms. Linnaeus’ An extensive component of a phi- simplistic system of organization is a clear ad- losopher’s thoughts is definition. Yet what is vancement from the hectic system of Aristo- definition but merely man’s attempt at us- tle. ing words to describe another word? This To formulate a conclusion of Aristotle’s creates an endless process of attempting taxonomy method is in some regards quite dif- to find the definition of a word and then the ficult. The philosopher died 2,331 years ago; definition of each word in the first definition. consequently, he cannot continue to defend However, Aristotle developed definitions of numerous words in an attempt to create an The logical arguments arise by following ba- organized structure or method of arranging sic logic. If a bird is a blooded animal and organisms into something called taxonomy. animals are egg laying or viviparous, then The modern definition of taxonomy is an or- birds are either egg laying or give birth to live derly classification of organisms. Aristotle felt young, but birds cannot be viviparous.1 Aris- that in order to classify something, it first had totle used the following example to defend to be defined. Based on his philosophy, de- his point: “Dichotomy splits natural kinds. If fining something required a two-step process. we divide animals into terrestrial and aquatic, First, a broad picture must be taken, mean- then we cannot go on to divide either side ing, “What kind is it?” This generalization de- into blooded/bloodless or polypod/footless, termines if it is a bird, fish, insect, etc. The sec- since there would have to be some of each ond step requires detailed information, such on each side.”2 The supporting example of as characteristics and properties, for the dif- his argument has validity to a certain degree. ferentia must be determined. The differen- It is true that dichotomy splits organisms, but tia is defined in the context of Aristotle as, “A the problem lies in the differentiae he uses to particular element or feature that defines one organize his taxonomy, such as blooded and entity from another.”1 An example of this defi- bloodless. Also, labyrinth-like organization nition would be limbs, whether they are wings, would be created if a system never split nat- fins, or forelegs. A definiendum is a set of char- ural kinds. The reason behind this statement acteristics or differentiae which defines an or- is the fact that living organisms have many ganism. Additionally, a definiendum must “re- similarities with other organisms. In defense of veal the object’s nature or substance.”1 The Aristotle’s method of organization, the knowl- final statement means that a definiendum is a edge which modern science has revealed to method of not only organizing and compar- us helps us better understand the design of ing organisms, but also defining or describing organisms, and therefore we can better orga- them. nize and categorize different organisms.2 According to the interpretation of Ar- Since Aristotle disagreed with the di- istotle’s writings, he believed the use of a di- chotomy system, he devised a system in which chotomy to organize organisms put limitations there are at least three differentiae simultane- on the system’s ability to distinguish organisms. ously. There were three rules which Aristotle The method of organization using dichotomy used to organize his taxonomy of organisms. is a process of using only one comparative First, a “Genus is in the category of substance, statement at a time. In other words, for every while differentiae are qualities.”1 The second division there are two options. Aristotle be- rule was “successive differentiation,” which is lieved there were severe logical consequenc- where each differentia is an addition to the es to utilizing such a method. As an example, previous one.1 The third rule goes back to the an animal can be divided into blooded and issue of a dichotomy where a genus must be bloodless. Blooded animals can be further di- divided multiple times simultaneously and not vided into egg laying and viviparous, mean- one at a time.1 Moreover, generic differentiae ing a bird is an egg laying, blooded animal. are used, which means that feathers, scales, Schemata | Spring 2010 and hair are all one differentiae based on anatomy of those organisms where they were the outer surface of the organism. By using his similar. Whether these groups of similar char- three rules, he determined that the best way acteristics were used in the organization of to compare organisms is by analyzing four dif- species, no one will know. The important prin- ferent classes of characteristics: body parts, ciple of his taxonomy structure is that he used life histories, actions, and disposition or psy- categories to organize and group organisms chology. By using those characteristics, an based on similarities. optimal scientific picture of an organism could Understandably thought provoking, be created. Once a complete definiendum the properties that Aristotle used to compare is determined for an organism, each living organisms are quite peculiar and for some, thing is placed into one of ten main groups rather ludicrous. In the History of Animals, Aris- or categories: man, viviparous quadrupeds, totle states, “Animals differ from one another oviparous quadrupeds, birds, fishes, ceta- in their modes of subsistence, in their actions, ceans, molluscs, crustaceans, testaceans, or in their habits, and in their parts.”3 When this insects.1 The first six are in the larger category statement is taken out of context, it is a valid of blooded and the last four are in the larger statement. However, by using an organism’s category of bloodless.1 Though vague, the habits as a method of comparative organiza- understanding of intermediate differentiae is tion, there are no definitive and unchanging that it encompasses many categories with- habits of a species of organisms. As individu- out direct order. Based on a comparative re- als and species adapt and evolve to live in view of numerous scholarly resources and the adverse conditions, their habits change. Ad- conclusions of the author, the organizational ditionally, the organizational pattern does not structure of Aristotle’s taxonomy includes a appear suited to organize millions of species genus and multiple differentiae. in one universal method. However, the primi- Multiple differentiae was Aristotle’s tive scientific knowledge of organisms greatly method of using categories to organize or- limited Aristotle in his ability to understand the ganisms. However, the issue of defining mul- relationship between organisms. tiple differentiae is difficult and subjective As years progressed and knowledge of according to a person’s conclusions on inter- the scientific field expanded, the methods of pretations. Within Aristotle’s works regarding organizing organisms became clearer and this subject, he makes mention of numerous easier. Additionally, the knowledge gained groups of organisms. However, what is not allowed the entire system to be greatly simpli- clear is whether these groups were meant to fied. A Swedish man, Carolus Linnaeus, was be a sub-genus classification. Moreover, it is born in 1707 as a poor man. He was a religious challenging to differentiate between notes man and one who strongly supported his cre- about organisms he dissected and notes per- ationist beliefs. These beliefs carried through taining to his method of taxonomy. Accord- into his development of a classification sys- ing to his records, he dissected hundreds of tem for organisms. He began his career as a organisms and recorded thousands of ob- medical doctor, but the love and fascination servations by investigating the comparative of plants caused him to become consumed Philosophy by the world of plants. He soon began to no- standards. Yet, in Linnaeus’ later writings he tice a hierarchy within organisms, especially discussed the issue of flexibility by declaring plants.4 that species have a lot of variation and there His system ignored slight variations within are many factors which cause this variation, species and instead used the “perfect speci- such as soil conditions. He also accepted men” to enable him to organize his system. the fact that hybridization between two dif- Linnaeus was influenced by John Ray, a natu- ferent species is possible. This long enduring ralist who died a few years before Linnaeus’ system has apparently been flexible enough birth. Carolus disagreed with Ray more than to withstand hundreds of years of tests against he agreed with him, but knowledge of the de- modern science.