John Stringer explores how civilisations have benefited by exchanging ideas.
From AD700 to 1300, Islamic scholars were at the forefront of science. Through trade, they came into close contact with people from many other cultures, including Chinese, Iranians, Turks, Jews and Christians, who contributed ideas to Islamic thinking.
The Chinese introduced them to paper. Paper books were widely available to Arab scholars, while European readers had access only to a few expensive parchments in Latin. In the ninth century, the library in Cordoba contained some 400,000 volumes, while the largest library in Western Europe had 36.
Arabic became the language of science. Words such as algorithm, azimuth, zenith and nadir reflect their Arabic origin, and algebra became a branch of modern mathematics.
How do we see? Early scientists, including Ptolemy in Egypt and Euclid in Greece, thought that the eye sent out visual rays. Many young children believe this today.
An Arab scientist - Alhazen - explained that light is reflected from the objects we see, and our eye is a receptor of that light.
Abu Hasan Ibn al-Haitham, or Alhazen, born more than 1,000 years ago in Iraq, was one of the Islamic scientists whose ideas still influence us today.
Alhazen used observation, hypothesis and experimentation to test his ideas. He wrote more than 200 books, and his writings influenced European scientists, including Roger Bacon and Leonardo da Vinci. He explored the way that light bends as it passes through water, and he investigated the use of lenses for magnification. He observed how the Sun changed colour as it set, and used his observations to calculate the height of the atmosphere.
LIGHT AND SIGHT
* In the footsteps of Alhazen
Refraction is the bending of light as it moves from one medium to another - for example, from air to water. Understanding of the principles of refraction has enabled us to develop lenses, such as those in a magnifying glass, binoculars and spectacles. Children can observe refraction by looking through a clear container of water. Ask pupils to: nexplore the way that light is bent as it travels from air into water; nnotice how a pencil appears to be bent when you put it in a jar of water; ntry dropping coins that will cover a 5p piece on the bottom of a bucket of water - is the target where it seems?
ntry looking at a picture through a jam-jar filled with water - what happens to the picture?
Arabic innovations included techniques for working with metals and ceramics, and the windmill. Water clocks had already been in existence for hundreds of years, but Arab scientists improved their accuracy and reliability. Arzachel made a water clock that could show the hours and the days of the lunar month. The first windmills, built in Iran around AD600, had a vertical shaft and horizontal sails.
Abbas Ibn Firnas was a ninth century musician who took an interest in flight - he made a pair of wings from feathers on a wooden frame.
Windmills A toy windmill can be used to raise light weights by securing the blades to the end of a shaft that spins horizontally, winding up a thread. Ask pupils to: nmake a windmill from paper and thin wood (see illustration below). Will it spin when they blow on the sails?
WORDS amp; NUMBERS
Arab thinkers and writers contributed greatly to both the number system and the language that we use today. Arab mathematicians, using figures similar to those we use now, developed the idea of place value, with zero representing an empty set. Islamic mathematicians learned how to use zero from the people of ancient India. Why is the zero important? After all, it means nothing! But if the zero was doing nothing, all these numbers would be the same: 016, 160, 106. The zero is doing an important job.
Pupils can practise their understanding of place value by using the same three numbers and adding one more zero in order to: make 016 stay the same;
make each number 10 times bigger;
Explore what happens to simple addition when the zero changes place value:
add 900 to 160;
add 900 to 106;
add 900 to 016.
In algebra (a word taken from Arabic), a letter such as x can stand for an unknown number: If 5 + x =13, what is x?
Some English words are Arabic in origin, though the pronunciation has changed - for example: alcohol, cipher, earth, safari, sugar, syrup.
Ask pupils to:
* write six sentences, each including one of the above words to illustrate its meaning. They can use a dictionary if they are not sure;
* use a dictionary to find the meanings of some of the following words, all derived from Arabic: monsoon, amber, cornea, alchemist; * use a dictionary to find the origins of other scientific or mathematical words; * look for other words that are Arabic in origin.
Historical backgroundPSHE There were several reasons for the development of Islamic science: Trade brought Arab scientists into contact with other cultures, stimulating ideas and innovation.
Paper, introduced from China in 751, made books relatively cheap.
Islamic tolerance of learning encouraged the exchange of ideas. nArabic became the common language of scientists.
While Western scientists still confused astronomy and astrology, Arab scientists rejected pseudo-science including alchemy and magic.
Many ideas that contributed to the development of science pre-empted Western thought by centuries. Much of our knowledge, and many mathematical concepts, were developed elsewhere. There's a clear message here about the benefits of openness to other cultures, and the value of building links with, rather than barriers against, other communities.
The key contribution of Arabic mathematics is the importance of place value and the use of zero as a place holder, enabling nine numerals plus zero to express all possible numbers. It is one of the key concepts children must come to grips with before they can tackle more advanced calculations.
A sentence to demonstrate understanding is not the same as a definition. A follow-up activity is to ask children to read out their sentences, and have a classgroup discussion on whether each sentence really shows the meaning. Other words originating in Arabic that we still use - often in a scientific context - include: almanac, cable, diaphragm, elixir, pancreas.
To help you make the most of Science Year 2002, the Early Years and Primary Teaching Exhibition in Manchester (May 1011) will feature a series of experiments by ex-teacher and in-service provider Dr Mark Bidiss. Visit www.teachingexhibitions.co.uk