 Why didn't Moran kill Harper?
I. Moran cut apart the yard-long monstrosity with a slash of flame. Moran, naturally, did not mean to help in the carrying out of the plans which would mean his destruction one way or another. The plans were thrashed out very painstakingly, in formal conference on the space-yacht Nadine , with Moran present and allowed to take part in the discussion. From the viewpoint of the Nadine's ship's company, it was simply necessary to get rid of Moran. Moran observed these things from the control-room of the Nadine , then approaching the world on planetary drive. Moran disagreed, but he did not answer. Without rigid control of space-travel, any criminal anywhere could escape the consequences of any crime simply by buying a ticket to another world. The trouble was that the Nadine had clearance papers covering five persons aboard—four men and a girl Carol. Wherever the yacht landed, such a disparity between its documents and its crew would spark an investigation. Moran, at least, would be picked out as a fugitive from Coryus Three. The others were fugitives too, from some unnamed world Moran did not know. And Moran was the extra man whose presence would rouse space-port officials' suspicion of the rest. Blaster in hand, he'd made the Nadine take off from Coryus III with a trip-tape picked at random for guidance. Only people accustomed to desperate actions would have remained so calm when Moran had used desperate measures against them.
 Moran is not a murderer at heart. He only killed the other man to save a life.
 Moran is not a murderer at heart. He only killed the other man to save a life.  Moran would rather kill Burleigh. He is waiting for the right moment.  Moran is not a killer.  Moran likes Harper. Harper is a decent guy.