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  "body": "\n## Statement\n\nLet $S \\colon \\mathbb{N} \\to \\mathbb{N}$ be the [[successor function|0832XVR512]] of the natural numbers.\nFor each natural number $n$, $S(n) \\neq 0$.\n\n## Remarks\n\nThis is one of the [[Peano axioms|0QFT7Z76N5]]. In a construction of $\\mathbb{N}$, it is a theorem.\nWith the [[injectivity of the successor function|0TBYMWPWWB]], it shows that the numbers $0, S(0), S(S(0)), \\dots$ are all different.\n\n## Explanations\n\n### L1 human\n\nWhen you count up from any natural number, you never get back to $0$.\nThus the natural numbers do not go around in a circle, like the hours on a clock do.\n",
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