The German branch of the ‘green’ organisation Peta (‘People for the ethical treatment of animals’) is demanding that, until men stop eating meat – apparently they cause 41 per cent more pollution than female carnivores – women must deny them sex. The same sanction had its origin, of course, in Aristophanes’s comedy Lysistrata (411 bc), staged during the war between Athens and Sparta (431-404 bc), just after Athens had suffered a disastrous defeat in a failed attempt on Sicily.