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  "body": "\n## Definition\n\nA [[set|0SJ3RX9TXA]] $A$ is uncountable when it is not [[countable|0ZG61TFBES]], that is, when there is no [[injective function|0PVG1CRAJN]] from $A$ to $\\mathbb{N}$.\n\n## Remarks\n\nThe real numbers and the [[power set|0BC7KX51Z8]] of $\\mathbb{N}$ are uncountable.\nWith the axiom of choice, a set is uncountable exactly when its cardinality is at least $\\aleph_1$, the least cardinal larger than $\\aleph_0$.\nA superset of an uncountable set is uncountable.\n\n## Explanations\n\n### L1 human\n\nFor an uncountable set, every attempt to list its elements misses some of them.\n[[Cantor's diagonal argument|0XCH8QVDCQ]] shows how to find a missing element.\n",
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