The book Mencius differs from the Analects in that many of the passages in the former are longer and more elaborate than those of the latter.  Mencius develops key points, engages ethical conundrums (might it be filial to disobey your parents?), and explicate key premises (Duty is internal; human nature is good) much more sharply than does Confucius.

     But there are some short, Confucius-like quotes in Mencius and none is more bracing than this:

Mencius said: "Great people’s words need not be sincere, nor their actions fruitful. They need only abide in Duty." (8.11)

     Yes, it is a rather straightforward defense of lying.  Here is an alternate translation from Lau:

Mencius said, ‘A great man need not keep his word nor does he necessarily see his actions through to the end.  He aims only at what is right.’ (4B.11).

     One of the great things about teaching is the way in which students keep you focused.  I have read this text many times but never fully appreciated the directness and import of this short passage until I discussed it with my students this week.   

      We should not take it as and overly general endorsement of lying.  I think he means that, in extreme circumstances, where ethical obligations collide, one may lie in the service of a greater good.  This reading would be in keeping with the story of the mythical sage-king Shun, who, Mencius tells us, found himself in the difficult position that required him to deceive his parents (usually an unfilial act) in order to marry (his depraved father would not permit him to do so) and thus realize the larger filial duty of creating a future family context within which Humanity could be enacted and realized. Not to marry would be an "act of hatred" against his parents; so, he had to disobey his parents ban on his marriage in order to be genuinely filial.

     We should be sincere, and not lie, most of the time.  But Mencius recognizes that sometimes lying might be morally necessary.  The trick is to know when, which a "great person" should be able to do.