CyberSchool Magazine

Ptolemy and the Universe
By Idil Boran

The school of Alexandria was founded around 350 B.C. Quickly, it became the latest, most brilliant, and successful astronomical school of ancient times. Many disciplines were taught in the Alexandrian school but the discipline that was given the greatest emphasis was astronomy. The school of Alexandria is now accepted by historians as a centre of science and culture, research and education with the longest duration. After its foundation, the school remained active until the 5th century of our era.

In 146 B.C. Greece was taken over by Rome and the astronomers, who were all Greek, continued their studies and research under the Roman Empire. The astronomers had access to many equipments for observation and the school also had observatories. In fact, the school of Alexandria was mostly famous for the quality of its observations.

Alexandria had two important astronomers, Aristarchus and Ptolemy. The former became famous with his heliocentric theory and the latter developed a theory of epicycles. Aristarchus' explanation of the universe was based not only on the revolution of the Earth around its own axis but he defended that the Sun was at the centre of the planetary system, and hence, at the centre of the universe. Unfortunately enough, Aristarchus' view of the universe, although ingenious, has been abandoned.

Two main explanations are given by historians of science for the abandonment of Aristarchus' vision of the universe. First of all, a physicist who is interested in knowing which bodies are at rest, which ones are in motion, and how they move has to use principles of dynamics. However, the principles of dynamics that Aristarchus as well as other astronomers of Alexandria had at hand were the principles of dynamics developed by Aristotle. Aristotle's principles of dynamics were based on the premise of the immobility of the Earth at the centre of the universe. Aristarchus was the only astronomer/mathematician who dared to disagree with Aristotle to the price of remaining marginal in the scientific community of his time.

The second explanation points to the fact that Aristarchus chose to give a merely qualitative explanation of the universe. His views theorized the universe and the planetary system by using qualitative explanations on how the Earth and the celestial bodies are organized vis-a-vis each other. His astronomical theory put little to no emphasis on a quantitative approach to support his theory with mathematical calculations regarding the motion of the celestial bodies. So, Aristarchus' explanations were not only quite extravagant for the mainstream views on physics of his time, but they lacked the quantitative rigour that is required from a scientist. Consequently, his theory failed to satisfy the need to come up with reliable rules and precise calculations in order to explain and predict celestial movements. As an alternative to Aristarchus' heliocentric system, Ptolemy introduced his theory of epicycles.

Claudius Ptolemaius of Alexandria was an important astronomer of the 2nd century. He has been very influencial in ancient times as well as throughout the middle ages until the Copernican scientific revolution. There is next to no information about his life. When he was born and when he died is not known. Historians can only locate the time of his life by assuming that the earliest observations that he described in his works were made by himself. His first recorded observation was made in 127 and the latest in 150. He lived and worked in Alexandria and it is estimated that he died after 161.

Ptolemy summarised his astronomical system in his treatise which became known in its Arabic subtitle "Almagest". The original Greek version of the book was entitled "The Mathematical System of Astronomy" but its admirers called it "Magiste Syntaxis" (i.e. The Great System). Later, when Arab scientists became interested in the Greek scientific works, Ptolemy's "Magiste Syntaxis" has been translated into Arabic. In its translation, the title simply became "Almagesti" with the addition of the Arabic article "al". Then, the book has always been referred to as the Almagest.

In the Almagest, Ptolemy's purpose was to represent all the observed motions of the heavenly bodies by means of mathematical formulae. The Almagest had the quantitative rigour that was important to support a scientific work. Some historians of science argue that Ptolemy's work comprised virtually all astronomical achievements which could be reached with the mathematical methods of the antiquity. Ptolemy's concern was to come up with a formulation of one single unified method to represent all celestial phenomena. To this end, he introduced the notions of "epicycles" and "eccentrics" to use in his geometrical theory of planetary motions.

Ptolemy's theory of planetary motions stood on four main principles:
1. The heavens is a sphere turning around a fixed axis.
2. The Earth is a sphere situated at the cenre of the heavens, otherwise, Ptolemy argued, one side of the heavens would appear nearer.
3. The Earth is but a point in comparison to the heavens, because, Ptolemy argued, no matter the place of the observer on the surface of the Earth, the size of the stars and the distances between them do not change.
4. The earth does not move, otherwise, according to Ptolemy, the animals and objects on the Earth would be thrown in the air.

The principles that Ptolemy adopted as well as the planetary theory that he developed suffered from a few problems. When observed from the Earth, certain planets like Mars, for example, seem to make looping movements. These looping movements looked like irregularities that, if left unexplained, would render the overall theory questionable. However, Ptolemy did what some historians and philosophers of science would accept to be a common maneuvre in scientific practices. He looked for a plausible explanation to save his theory rather than changing it. In other words, the theory had be able to explain those looping movements without contradicting itself. For this, Ptolemy introduced his theory of epicycles and deferrents.

The theory of epicycles and deferrents consisted in the use of smaller spheres which were fixed on the larger ones. The smaller sheres were called the epicycles and the larger ones were called deferents (or carriers). According to the theory of epicycles and deferents, each planet was supposed to be fixed on a small circle (i.e. epicycle) and the small circle was fixed on a large one (i.e. deferent). So, the theory of epicycles and deferents could be considered as a theory of a small orbit within a larger orbit. Mars, then, was considered to be turning around a small orbit. And the small orbit was turning around a bigger orbit whose centre was considered to be the earth. The rotation of Mars was believed to produce a spiral shape around the Earth. This is how Ptolemy explained the three aspects of the rotation of the planet; regular, stationary, and retrogradal.

Ptolemy used the theory of epicycles and deferents to come up with a whole astronomical system. The epicycle and the deferent of each planet were calculated proportionally according to the observed size and speed of the planet. Because the Sun and the Moon were considered planets, Ptolemy calculated an epicycle and a deferent for the Moon and a deferent for the Sun.

Ptolemy accepted the view that one must adapt the simplest hypothesis to the celestial movements, but if this does not succeed one must take the acceptable ones. Consequently, Ptolemy's system became increasingly complex for each time the theory was facing a problem Ptolemy was adding a supplementary theory, like the addition of eccentrics to explain the oscillatory movement of planets. Accordingly, some celestial bodies were considered to be rotating around a different centre. These orbits were called eccentrics.

Ptolemy's earth-centered and multispheric astronomical system explained the movement of celestial bodies without contradicting the view of the Earth being at the centre of the universe. However, the explanation of the universe in terms of epicycles, deferents, and eccentrics became extremely complex and hardly manageable. Ptolemy was a very influencial astronomer throughout centuries. His doctrines guided astronomy until the Copernican scientific revolution displaced the Earth from the centre of the universe in the 16th century.



Puppets Learning and Play: Diverse Applications of Communicative Play as a Learning System

Jeffrey L. Peyton

Jeffrey L. Peyton, is the inventor of "Puppetools,"

Play: The Solar Energy for Education. As a fundamental element of life, inherent in all forms of matter, play is at work in natural symmetry and random events throughout the universe. Play has evolved to its highest expression in mammals as a specialized form of learning behavior. Play has been identified as a critical factor in socialization and child development. In an evolutionary sense, play is the wellspring of learning. In modern terms, play may be viewed as nature's most intelligent learning system. It is also the mental soil upon which great inventors and scientists establish their work.

Nevertheless, the value of play is often overlooked and its effects are not seriously considered. In schools, students forfit play as they ascend the grades. Even though research on play behavior relating to early childhood education fills the shelves of bookstores and academic libraries, a recent search of the literature reveals no research on the subject of adult-child play relationships. To Paul D. MacLean, Senior Research Scientist, Department of Neurophysiology, National Institutes of Mental Health, the subject of play has proved similarly elusive in the field of brain science: In view of the prominence of play among mammals and its civilizing influence in human evolution, it is curious that it has received so little attention in neurobehavioral research. In one handbook of experimental psychology, for example, the subject of play is dealt with in less than a page, and in a three-volume handbook of neurophysiology, there is no reference to play.

The Tools of Communicative Play: If play can be defined as an evolutionary invention, there is, interestingly, a related a behavioral expression of play and communication unique to the human realm. This refers to what are commonly known as "puppets". The ancient hand puppet has long been recognized as a symbol of play and more recently as a tool for learning. In a popular vein, puppets are widely recognized for their beneficial influence on learning and social development and have been shown to exert a powerful influence on children of all ages.

But there is more to puppets; a teacher can personally transform common learning barriers, oppositional behavior, negative moods, defensive attitudes into a windfall of learning benefits and surprises. Children become more responsive and motivated. Teachers find themselves suddenly having fun. Teachers who tend to keep themselves and their emotions at arm's distance in the classroom become fully involved with the puppets and the children's response to them.

The element of play induced by puppets calls up in teachers and children something vital to a learning process struggling to rise above itself. What many teachers describe as magical in puppets Peyton has come to see as the fruits of the brain's deeper nature in response to vocalization, movement, and visual information associated with a powerful species-typical behavior. Thus wrapped in the temporal puppet dynamic may be found the physical expression of neurological and evolutionary events foundational to human learning.

Puppet Behavior & Brain Science According to Peyton, puppet play is a form of spontaneous, species-typical behavior that induce predictable individual and group responses. It is similar to specialized behaviors in other life forms with which we share common neurological building blocks. Like laughter, spontaneous puppet behavior can be understood, quite literally, as an event that provides insight into learning behavior. Puppets are at once a scientific looking glass and a mirror complete with a handle by which to gain an objective picture of our subjective selves. As satellites of consciousness, the doll, the animated hand puppet, or the mouse connected to a computer work in tandem with the main body. These attached and related entities represent aspects of ourselves which serve to reflect to filter, to project, and to help us grasp the essence of our nature and the nature of our ideas.

To the same extent that the structures within our brains have evolved in proximity to one another to invite the playful leaping back and forth of electrical energy in the synapses, artifacts such as the hand puppet and the computer are just far enough away to allow a similar jump of impulses where things go pop, leap, move back and forth and connect in a process that bootstraps and reinforces the development of memory and consciousness. The spontaneous, interaction induced by a hand puppet is a non-closed, self-revealing act, a reflection of the brain's expansiveness; an expressive artifact of the brain's recognition system that operates selectively (as opposed to instructively) and is ever unfolding and moving beyond itself.

While it is true that children play with all kinds of artifacts that are often made to talk, the focus is on the development of a suitable medium that can be developed and systematically applied in school settings and throughout the learning-communication infrastructure.Hold That Thought!

To make puppets a practical option for teachers, Peyton has reinvented the concept of puppet, turning the old model of cloth forms, scripts, and stages into an open-ended language of symbols and ideas. His patented system demonstrates that the common cultural conveyor we know as paper can be transformed into a visual, play-driven communications platform. In this view, the hand puppet is a part of speech in a limitless learning language based on the need to communicate through play. The behavioral dynamics of puppet behavior are extracted, re- formatted, and mainstreamed via a Windows-like operating system that makes any idea visual to the eye and accessible to the hand in preschool to college foreign language classrooms. Simple paper puppets become hand held ideas, a powerful, low-cost communication resource. Peyton's succesful merging of the puppet medium into the common classroom staple attests to its potential as soft technology to achieve a full integration of play energy into the learning infrastructure and emerging technologies. The successful application of play and paper opens the door to extended applications in common cultural carriers such as books and come to this curious medium than meets the eye.

The simple act of puppet play engaged in by child and adult in which a lifelike forum or behaving entity is made to move and talk produces a catalytic, predictable impact on classroom group dynamics. These dynamics are routinely set in motion by Jeffrey Peyton, originator of Puppetools. Peyton has spent 25 years conducting workshops and studying the powerful effect of puppet play on communication and adult-child relationships in the classroom.This work has generated an extensive base of teacher anecdotes and video documentation attesting to the changes which classrooms undergo after introducing and working with the puppet medium. Its first-time impact recorded in teachers' journals often reiterate many comments such as follows: "I can hardly believe that a paper puppet can be so magical. The children were mesmerized." "This has been one of the most enjoyable first few weeks of school I can remember," wrote one teacher who had recently discovered the medium.

Using computers which also use paper. His on-line teacher education programs, which are offered by The New School for Social Research in New York City, demonstrate that teachers can be trained in the use of communicative play via computers; that human dynamic solutions can be delivered by new technology. Peyton's Einstein Curriculum, which is offered on-line, is intended to help educators make the shift from a text-based environment to a more visual-emotive, Windows- like platform for communicating, relating ideas, and learning, "A Windows'-like Operating System for The classroom."

A visual-linguistic operating system based on principles of communicative play can be employed to achieve the following objectives: lift classroom experience into a visual and emotive communication to infuse greater meaning and interactivity innovate existing and prospective learning systems and promote diversity of thought; destabilize the repetitious, enculturated communication patterns that inhibit change; carry a healing, bonding, and sensitizing nutrient that civilizes and warms learning environmentsprepare students to use visual and global thinking which computer-age challenges will require of them; reverse the common misperception of learning disabilities to a more inclusive view (ie. that disabilities often indicate capacities for visual and global thinking, given the trend toward mainstreaming, it is imperative that a diverse population of learners be reached;) equip educators with basic working knowledge of the brain using an approach that incorporates the use of play to create formative learning experiences.

Important Lessons in Brain Science for Educators 1.The brain is a selection instrument. It seeks new information on the basis of recognition, not instruction, and play. 2. Play process provides ingredients that foster a healthy quality of mind: openness, spontaneity, unpredictability, all- important operating characteristcs of the healthy brain. 3.The brain's primary mode of communication is nonverbal and visual.4. Play is an evolutionary invention linked to speech, nurturing, and learning in mammals.

Play can be harnessed to drive the learning process and to lead us into a greater understanding of our intelligence. By designing an intelligence system that functions according to the evolutionary imperatives embodied in play, appropriate forms and levels of communicative play can be directed into the learning process. In so doing, we begin to grasp the special nature of play and open doors to a full and integrated use of brain resources, to enhanced perceptions, sensitivities and mental literacy; and to a more enlightened education whose foundations are predicated upon the structures and physiology of the brain itself.

References: Why Children Talk to Themselves, by Laura E. Berk, Scientific American, November, 1994. Vigotsky's Theory: The Importance of Make-Believe Play, by Laura E. Berk, Young Children, November 1994. Why Dogs Bark, presented at the 1993 American Association for the Advancement of Science annual meeting. Why Children Talk to Puppets, by Jeffrey L. Peyton, pulished website document. The Triune Brain in Evolution, by Paul D. MacLean, (Plenum Press, 1990.)

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