A dictionary of Proverbs (Oxford Paperback Reference)

If you can’t RIDE two horses at once, you shouldn’t be in the circus
James Maxton, to whom this saying is attributed (quot. 1935), was a British Independent Labour Party MP (1932-46). Denis Healey (see quot. 2002), another British Labour politician, was probably consciously quoting Maxton.

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  1935 G. MCALLISTER James Maxton xiv. Maxton made a brief intervention in the debate to say . . that he did not believe it was necessary to pass a resolution for disaffiliation [of the ILP from the Labour Party]. He had been told that he could not ride two horses. ‘My reply to that is’, he said.. ‘that if my friend cannot ride two horses— what’s he doing in the bloody circus?’ 1979 Daily Telegraph 15 Mar. 15 A producer who ‘can’t ride two horses at the same time shouldn’t be in the circus.’.. Current affairs television should be both serious and entertaining. 2002 National Review 3 June 18 But politics is a practical activity, not an intellectual one. As Denis Healey once said, if you can’t ride two horses at once, you shouldn’t be in the bloody circus. ■ efficiency and inefficiency; stress
  

ride see also set a BEGGAR on horseback, and he’ll ride to the Devil; if TWO ride on a horse one must ride behind; if WISHES were horses beggars would ride.
He who RIDES a tiger is afraid to dismount
Once a dangerous or troublesome venture is begun, the safest course is to carry it through to the end.

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  1875 W. SCARBOROUGH Collection of Chinese Proverbs no. 2082 He who rides a tiger is afraid to dismount. .. Ch’i ‘hu nan hsiapei. 1902 A. R. COLQUHOUN Mastery of Pacific xvi. These colonies are.. for her [France] the tiger which she has mounted (to use the Chinese phrase) and which she can neither manage nor get rid of. 1983 W. HARRISS Bay Psalm Book Murder x. ‘But no doubt about it, I’ve got a tiger by the tail now.’ ‘And there’s an Oriental saying that the man who rides the tiger is afraid to get off. Watch your step.’ "peril