"No.  But I was not laughing at the little monkey.  I was laughing at you people.  And I suddenly knew that I was people and could not stop laughing." He paused. "This is hard to explain, because you have never lived as a Martian, for all that I've told you about it.  On Mars there is never anything to laugh at.  All the things that are funny to us humans either physically cannot happen on Mars or are not permitted to happen - sweetheart, what you call 'freedom' doesn't exist on Mars; everything is planned by the Old Ones - or the things that do happen on Mars which we laugh at here on Earth aren't funny because there is no wrongness about them.  Death, for example."