If you are not reasonable, what are you?

I only ask, because Unison general secretary Dave Prentis has been criticising Labour for making reasonable comments:

In an interview with The Independent on Sunday, the Unison general secretary suggested the Labour leader can no longer count on his union’s automatic support when he said he still has “a lot to get right” and should abandon the strategy of only issuing “reasonable statements”. [Independent on Sunday]

‘Comrades, we must be unreasonable!’ certainly would be an effective demand – if you wanted to caricature yourself into unpopularity.