Mathematics, the father of natural science, originated from the great invention of natural numbers used for counting.
A few years ago, in order to survive, human ancestors often lived in groups of dozens. They work together during the day, searching for wild animals and birds or collecting fruit and potato food; Live in a cave at night and enjoy the labor income. In the long-term labor and life, they gradually reached the point where they had to say something, so language came into being. They can express their feelings and exchange ideas with simple language and gestures. With the development of labor content, their languages have also developed continuously, and finally surpassed the languages of all other animals. One of the main signs is that language contains the color of arithmetic.
Humans first came up with the hazy concept of "number". When they came back from hunting, their prey might or might not be there, so they had two concepts of "yes" and "no". After a few days of catching animals that don't, there will be no meat to eat, and the concepts of "yes" and "no" will gradually deepen.
Later, social groups developed into tribes. Tribes are made up of families with few members. The so-called "you" can be divided into one, two, three and more (some tribes don't even have three). Any quantity greater than three is understood as "many" or "a pile" or "a group". Although some chiefs are elders, they can't tell how many kinds of wild animals they have caught and how many kinds of trees they have seen. If you ask a witch doctor, he will make up some words to answer the question "How many kinds" and then recite them solemnly. However, in any case, they can already make it clear with their hands (one refers to the deer and three refers to the arrow): "For a deer, you have to give me three arrows." This is arithmetic knowledge that they didn't have at that time.
About/kloc-0.0 million years ago, glaciers retreated. Some stone age nomadic hunters started a new way of life-farming in the mountains of the Middle East. They encountered some problems, such as how to record the date and season, and how to calculate the number of grains and seeds collected. Especially in the Nile Valley, Tigris River and Euphrates River basins, when more complicated agricultural society developed, they also encountered the problem of paying land rent. This requires numbers to have names. In addition, the counting must be more accurate. Only "one", "two", "three" and "many" are not enough.
Between the Tigris and Euphrates rivers and around them, it is called Mesopotamia, where a culture, like Egyptian culture, is one of the oldest in the world. Although Mesopotamia and Egypt are far apart, they established the earliest system of writing natural numbers in the same way-marking and marking trees or stones to record the passing days. Although the shapes of numbers are different, they are similar. They all use a single stroke to represent "one".
Later (especially after they settled in the village), symbols gradually replaced nicks, that is, 1 symbol stands for 1 thing, 2 symbol stands for 2 things, and so on. This counting method lasted for a long time. About 5000 years ago, Egyptian priests wrote digital symbols on a papyrus made of reeds, while Mesopotamian priests wrote them on soft clay tablets. They still use a single stroke to represent "-",but also use other symbols to represent "+"or larger natural numbers; They use these dashes and symbols repeatedly to represent the numbers they need.
In BC 1500, the Inca people in Peru, South America (part of the Indians) used to "tie ropes and count"-tie a knot on the rope every time a bundle of crops was harvested, and record the harvest with the number of knots. The function of "knot" is the same as that of mark, and it is also used to represent natural numbers. According to the Book of Changes, people in ancient China also "ruled the country by knots", that is, tied a knot on a rope to record events. Later, it was changed to "book deed", that is, it was carved on bamboo or wood with a knife, and a pen represented "one". Today, we in China often use the word "positive" to count. Each stroke represents "one". Of course, the word "positive" also contains the meaning of "five into one"