(This is the second edition) You can see the power of logic in Descartes' "I think, therefore I am," which proves the existence of the "Self" without the need for scientific measurement. In this book, firstly in an article, I will try to prove the following truth: "The whole universe" (the whole world) is infinite, eternal, and transcends time with the power of logic. I think this worldview could be the basis for universal happiness for everyone in "the whole universe," if each of us does not stick to our own standpoints. The word "whole" implies "holiness." I feel a mystery in the nature of the existence of "the whole universe." I have included two rather easy-to-understand papers that originated the main thesis, which is rather difficult and rigid in style. The two papers are placed before the main thesis in this book. Secondly in an essay, I will try to explain what happiness is, and how one can be happy. Then, some of my other essays and articles will be included in the third part. I hope this book will be your light in the darkness.