ちょっと怖い橋もありました。先が見えません。この先へ進んだら殺人鬼の住む小屋がありそうじゃないですか？ The sets utilized to define natural numbers satisfy the Peano axioms. It follows that each theorem which can be stated and proved in Peano arithmetic can even be proved in established principle. There's two regular solutions for formally defining natural numbers. The main one particu... https://buynostresscapsules.blogspot.com/