A dictionary of Proverbs (Oxford Paperback Reference)

rose-water see REVOLUTIONS are not made with rose-water.
rot see ONE for the mouse, one for the crow; WINTER never rots in the sky.
The ROTTEN apple injures its neighbour
The proverb is also found in a number of variant forms, some of which are illustrated below. Cf. L. pomum compunctum cito corrumpit sibi junctum, a rotten apple quickly infects its neighbour.

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  1340 Ayenbite of Inwit (EETS) 205 A roted eppel amang the holen [whole ones], maketh rotie the yzounde [sound]. 1577 J. NORTHBROOKE Treatise against Dicing 95 A peny naughtily [dishonestly] gotten, sayth Chrysostome, is like a rotten apple layd among sounde apples, which will rot all the rest. 1736 B. FRANKLIN Poor Richard’s Almanack (July) The rotten apple spoils his companion. 1855 H. G. BOHN Hand-Book of Proverbs 514 The rotten apple injures its neighbour. 1979 D. MACKENZIE Raven feathers his Nest 19 The police.. have a deserved reputation for uprightness. .. But one bad apple can spoil the whole barrel. ■ associates; example, good and bad
  

rotten see also SMALL choice in rotten apples; SOON ripe, soon rotten.
roundabout see what you LOSE on the swings you gain on the roundabouts.
There is no ROYAL road to learning
Cf. PROCLUS Commentary on Euclid (Friedlein) 68, м "•.’V'-?.’ jr.-nfmv
the -.:rr;j.'l?;-. there is no royal short cut to geometry (quoting Euclid). 1745 E. STONE tr. Euclid’s Elements (ed. 2) II. A2^V There is no other Royal Way or Path to Geometry.

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  1824 EMERSON Journal (1961) II. 268 There is no royal road to Learning. 1857 TROLLOPE Barchester Towers II. i. There is no royal road to learning; no short cut to the acquirement of any valuable art. 1941 H. G. WELLS You can’t be too Careful II. vi. ‘There’s no Royal Road to Learning,’ said Mr. Myame. ‘No. “Thorough” has always been my motto.’ 1995 Nature 26 Jan. 297/3 There are well-established criteria by which to distinguish homology from homoplasy but there is still no royal road to truth. "diligence; learning; ways and means