Definition: 7.01: Unit
(Definition 1 from Book 7 of Euclid's “Elements”)
A unit is (that) according to which each existing (thing) is said (to be) one.
Modern Definition
see existence and uniqueness of integer one.
Mentioned in:
Corollaries: 1
Definitions: 2 3 4 5 6
Proofs: 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
Propositions: 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73
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References
Adapted from (subject to copyright, with kind permission)
 Fitzpatrick, Richard: Euclid's "Elements of Geometry"
Adapted from CC BYSA 3.0 Sources:
 Prime.mover and others: "Pr∞fWiki", https://proofwiki.org/wiki/Main_Page, 2016