A dictionary of Proverbs (Oxford Paperback Reference)

tyranny see BETTER a century of tyranny than one day of chaos.
undone see what’s DONE cannot be undone.
The UNEXPECTED always happens
Similar to NOTHING is certain but the unforeseen. Cf. PLAUTUS Mostellaria I. iii. 197 insperata accidunt magi’ saepe quam quae speres, unexpected things happen more often than those you hope for.

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  1885 E. J. HARDY How to be Happy though Married xxv. A woman may have much theoretical knowledge, but this will not prevent unlooked-for obstacles from arising. .. It is the unexpected that constantly happens. 1909 Times Weekly 12 Nov. 732 No place in the world is more familiar than the House of Commons with ‘the unforeseen that always happens’. 1938 E. WAUGH ScoopI. iii. Have nothing which in a case of emergency you cannot carry in your own hands. But remember that the unexpected always happens. 1977 L. J. PETER Peter’s Quotations 296 Peter’s Law—The unexpected always happens. ■ certainty and uncertainty; foresight and hindsight
  

unforeseen see NOTHING is certain but the unforeseen.
UNION is strength
Unity is a popular alternative for union, especially when used as a trade-union slogan. Cf. HOMER Iliad XIII. 237 j,. -, even weak men have
strength in unity; L. vis unita fortior, force united is stronger; c 1527 T. BERTHELET tr. Erasmus’ Sayings of Wise Men A4^V Concorde maketh those thynges that are weake, mighty and stronge.

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  1654 R. WILLIAMS Complete Writings (1963) VI. 280 Union strengthens. 1837 in D. Porter Early Negro Writing (1971) 228 In Union is strength. 1848 S. ROBINSON Letter 29 Dec. in Indiana Hist. Collections (1936) XXII. 178 ‘Union is strength,’ and that is the only kind that can control the floods of such a ‘great father of rivers [the Mississippi]’. 1877 E. WALFORD Tales of Great Families I. 264 The prosperity of the House of Rothschild [is due to] the unity which has attended the co-partnership of its members.. a fresh example of the saying that ‘union is strength’. 1933 H. ADAMS
  

Strange Murder of Hatton xxix. Union is strength. We, by pooling our resources,.. are able.. to secure a steady income. 1981 E. AGRY Assault Force ix. This unfortunate misunderstanding; we must clear it up. .. After all, unity is strength. ■ strength and weakness; unity and division