A dictionary of Proverbs (Oxford Paperback Reference)

The BEST-laid schemes of mice and men gang aft agley
Often used allusively in shortened form (see quot. 1911). Gang aft agley means ‘often go awry’.

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  1786 BURNS Poems 140 The best laid schemes o’ Mice an’ Men, Gang aft agley. 1911 D. H. LAWRENCE Letter 21 Sept. (1979) I. 305 I am sorry the bookbinding has gone pop. But there ‘The best laid schemes’ etc. etc. 1996 H. P. JEFFERS Reader’s Guide to Murder xxvii. 179 But, like the man said, ‘The best laid plans of mice and men often go awry.’ "intentions; wanting and having
  

The BEST of friends must part
Cf. c 1385 CHAUCER Troilus & Criseyde v. 343 Alwey frendes may nat ben yfeere [may not be together].

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  1611 G. CHAPMAN May-Day IV 70 Friends must part, we came not all together, and we must not goe all together. 1685 J. DUNTON in Publications of Prince Society (1867) 10 But the dearest friends must part. 1784 J. F. D. SMYTH Tour in USA I. xxxvii. Sooner or later, all, even the dearest of friends, must part. 1821 SCOTT Kenilworth I. xi. ‘You are going to leave me, then?’.. ‘The best of friends must part, Flibbertigibbet.’ 1979 W. GOLDING Darkness Visible ii. ‘Aren’t there going to be any more lessons?’.. ‘The best of friends must part.’ "absence; friends
  

The BEST of men are but men at best
The General Lambert referred to in quot. 1680 was the Parliamentarian commander John Lambert (1619-83), who played an important role in Cromwell’s military victories over the Royalists in the English Civil War.

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  1680 J. AUBREY Letter 15 June in Brief Lives (1898) I. 12 I remember one sayeing of generall Lambert’s, that ‘the best of men are but men at best’. 1885 T. HARLEY Moon Lore 191 We can but repeat to ourselves the saying, ‘The best of men are but men at best’. 2006 Africa News 16 April (online) The suave and customer-friendly postal officers exercised the required social graces, ensuring that their customer understood, even sympathised with, these seemingly able and efficient Kenyans, toiling under an imperfect international postal system. After all, ‘the best of men are men at best.’ "human nature; pragmatism; virtue