2003NSIII　「自然の化学的基礎」　

　"Water is the arch� of all things" Centuries have passed since the Greek philosopher Thales advocated his belief of water being the primary and universal element. Other thinkers proposed similar thoughts emphasizing air, earth, fire, and the integration of all these, but what we perceive from human relationship with nature apparently confirms this statement to a considerable extent, reaffirming the significance of water in human lives, regardless of progress.

　 Water already proved necessary for those living in the primitive ages. Supporting animism, the worldﾕs four greatest civilizations ﾐ Chinese, Indian, Egyptian, and Mesopotamian ﾐ depended greatly on the supply of water and nature. Early drawings on the surface of walls convey, for example, the role of the Nile River in agriculture, dyeing, and production of paper (papyrus) in ancient Egypt.

　Greek philosophers, in contrast, held views of matter not necessarily as modern as these developed Egyptians. They sought to discover the essence of nature, and each found the greatest value in distinct dimensions of the planet. However, a universal understanding of water did exist. According to them, water was necessary for living things, capable of transforming into diverse shapes, and existed in all things, even in solids.

　Empedocles formed a Four Element Hypothesis in 450BC that fire, air, earth, and water formed the four elementary substances. This thought suggested that the natural world comprised of 1) a change brought by the integration (=love) of two materials, and 2) another change triggered by the decomposition (=hate) of a substance. The legendary Aristotle later expanded on this theory, asserting that each of the four elements possessed distinct qualities, and a change in the combinations would result in converted elements.

　Later in 400BC, Democritus pronounced that atoms were the basis of all forms of matter, also referred to as the Atomic Hypothesis. He argued that matter would always cease to minimize from its smallest form, the atom, and thus was incapable of reaching extinction. This idea soon revived as the Atomic Theory proposed by Dalton, while the Four Element Hypothesis by Aristotle continued to stay firm during the 1700s, even creating the basis for alchemy. All of these principles held their bases not in science but in philosophy, and thus did not offer ways to distinguish between right or wrong.

　 A period of scientific establishment surfaced in the 1650s, however, now calling for social and cultural requirements. Unlike previous eras emphasizing unverifiable ideologies, truths based on experience and experiments came to shape the heart of this new period. Robert Boyle, who wrote The Skeptical Chemist in 1661, declared that truth must be sought for and only for truth itself. This attitude proved to be sharply in contrast with the previous times, in which people simply pursued their own benefits. Experiments and observations now allowed chemistry to become a member of natural science. Assertions on induction, matter, and particles also served to vitalize this arising period, soon to be followed by one of chemical revolution and modern science.

　Through much research and understanding of the worldﾕs resources, human beings have achieved a great deal of information on water and its relationship with the natural environment, along with that with humans themselves. As Thales proclaimed, water participates in multiple spheres: ashes, compound ingredients, and photosynthesis, as well as in various forms: rain, snow, clouds, ice, steam, fog, rivers, oceans, etc. During its circulation, for example, evaporated water cleanses contamination through rain and snow, and prevents incandescence from solar heat by removing heat energy. Thus, water acts as a controlling power of the earthﾕs weather conditions, and all plants and animals survive within this same circulatory system. The environment today, however, faces serious danger concerning each of its dimensions. Pollution, pavements, deforestation, and the inflow of poisonous or harmful substances due to our overuse severely damage the finite resources.

　Water consumes a surprisingly significant portion of our lives, and reflecting not only on large-scale technological advancements but also on our everyday lives indicates how dependent we continue to be on water. In fact, 70% of our bodies form water. 99% of the liquid discharged from our bodies are reabsorbed as intake, functioning as an efficient water regulator. Sweat, excretion, and aging necessitate water as well, again implying our dependency on this substance from the very moment of our birth until our death. Our attempts to try and learn about water as well as nature, therefore, automatically signify an effort to gain knowledge on ourselves.

　 However, at the same time we cannot simply evaluate water as the ﾒsolelyﾓ　ultimate substance on earth and overlook the various other elements within the natural environment. Water undeniably serves as a foundation, a basis of so much of our surroundings today, and to live even a day without it is just out of the question when every human being continues to take the wonder of water for granted. Yet, can we then survive with only water? To question the origin of water links to the beginning, not only of the earth, but also of the universe. The formation of up to 92 elements took place at this time. The heavier elements, namely iron, aluminum, sodium, calcium, and magnesium formed the earthﾕs crust, while the lighter ones turned into components of the atmosphere. On the day of the ﾒgiant impact,ﾓ the collision resulted in the creation of the moon, which then caused much movement on the ocean floor. Surprisingly, bacteria, receiving energy from hydrogen sulfide, is known to be the closest to the very first form of life. Even in the Genesis, God is said to have created light on the first day, previous to water. It is truly amazing to imagine that before the birth of the earth, the fundamental elements we refer to in science had begun to shape themselves toward a new era.

　The sea, or in other words, water, indeed witnessed itself as the location for the creation of the first life, and continues to support the development of living things. We all originate from water, and continue to carry it within us as well as around us. Our connection with it has lasted since the most primitive times, which may explain the feeling of tranquility we encounter when surrounded by water: it is our instincts subconsciously responding to the attraction of this magical substance. As we trace back to the very beginning of all things, though, we also realize that these other substances similarly played remarkable roles in successfully leading the earth to its creation, or in the long run, even what we appreciate today. Thalesﾕs words definitely serve as a reasonable, meaningful statement, especially in contemporary society. Taking into consideration the countless forms of matter and their comparable importance with that of water, we human beings must face the task of ﾒsavingﾓ these precious substances that we have continued to take for granted for so long.

Bibliography

"Chemistry Historical Introduction." <http://www.slvhs.slv.k12.ca.us/~pboomer/notes/chemhistorical/chemhist.html> 24 Feb 2004.

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