Up | Japanese

"How is circle made?"

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We know the "circle" in the sense that we can recognize "circles". The subject here is to make a circle, that is, to realize the shape of "circle". The mathematical way of understanding a circle is nothing but constructing a circle. And here, "center" and "radius" are introduced as the elements of construction. The following is the mathmatical way of understanding "circle" : There is a big gap between "being able to recognize" and "being able to make". While our concern stays at "recognition", there is no mathematics. When "production" becomes an issue, mathematis comes. In fact, "being able to introduce the concept of center and radius" is not trivial. Center and radius are invisible. Things of the shape of circle, by themselves, does not imply "center" and "radius". They are our creation. Remember. Mathematics is a tool for production which human beings created and have been developing.